• 80dB now but still needs improvement at 1KHz

    From Edward Rawde@21:1/5 to All on Sun Nov 3 23:06:04 2024
    Simulation isn't fast but if you let it complete and do an FFT on the last 30 seconds, it's 80dB down at all unwanted harmonics.
    There do however seem to be unwanted sidebands close in either side of 1KHz
    Any suggestions for improvement?

    Version 4
    SHEET 1 2196 932
    WIRE 400 -704 368 -704
    WIRE 608 -704 464 -704
    WIRE -80 -624 -176 -624
    WIRE 16 -624 -80 -624
    WIRE 112 -624 96 -624
    WIRE 128 -624 112 -624
    WIRE 240 -624 208 -624
    WIRE 336 -624 240 -624
    WIRE 368 -624 368 -704
    WIRE 368 -624 336 -624
    WIRE 400 -624 368 -624
    WIRE 512 -624 464 -624
    WIRE -80 -608 -80 -624
    WIRE 240 -592 240 -624
    WIRE 336 -576 336 -624
    WIRE -176 -544 -176 -624
    WIRE -208 -496 -288 -496
    WIRE -80 -496 -80 -528
    WIRE -80 -496 -112 -496
    WIRE 0 -496 -80 -496
    WIRE 240 -480 240 -512
    WIRE 288 -480 240 -480
    WIRE 336 -480 336 -512
    WIRE 336 -480 288 -480
    WIRE 112 -464 112 -624
    WIRE 288 -448 288 -480
    WIRE 320 -448 288 -448
    WIRE 320 -432 320 -448
    WIRE 288 -400 288 -448
    WIRE 288 -400 240 -400
    WIRE 336 -400 288 -400
    WIRE -288 -368 -288 -496
    WIRE -192 -368 -288 -368
    WIRE 0 -368 0 -496
    WIRE 0 -368 -112 -368
    WIRE 240 -368 240 -400
    WIRE 336 -352 336 -400
    WIRE 416 -336 384 -336
    WIRE 608 -336 608 -704
    WIRE 608 -336 480 -336
    WIRE -80 -256 -176 -256
    WIRE 16 -256 -80 -256
    WIRE 112 -256 112 -400
    WIRE 112 -256 96 -256
    WIRE 144 -256 112 -256
    WIRE 240 -256 240 -288
    WIRE 240 -256 224 -256
    WIRE 336 -256 336 -288
    WIRE 336 -256 240 -256
    WIRE 384 -256 384 -336
    WIRE 384 -256 336 -256
    WIRE 416 -256 384 -256
    WIRE 512 -256 512 -624
    WIRE 512 -256 480 -256
    WIRE -80 -224 -80 -256
    WIRE 512 -224 512 -256
    WIRE 608 -224 608 -336
    WIRE -176 -176 -176 -256
    WIRE -288 -128 -288 -368
    WIRE -208 -128 -288 -128
    WIRE -80 -128 -80 -144
    WIRE -80 -128 -112 -128
    WIRE 0 -128 0 -368
    WIRE 0 -128 -80 -128
    WIRE 176 -128 0 -128
    WIRE 288 -128 256 -128
    WIRE 320 -128 288 -128
    WIRE 448 -128 400 -128
    WIRE 288 -16 288 -128
    WIRE 288 -16 -80 -16
    WIRE 320 -16 288 -16
    WIRE 448 -16 448 -128
    WIRE 448 -16 400 -16
    WIRE 48 48 48 32
    WIRE 448 48 448 -16
    WIRE 512 48 512 -144
    WIRE 512 48 448 48
    WIRE -80 96 -80 -16
    WIRE 16 96 -80 96
    WIRE 448 96 448 48
    WIRE 448 96 176 96
    WIRE 16 160 -80 160
    WIRE 592 160 176 160
    WIRE 608 160 608 -144
    WIRE 608 160 592 160
    WIRE 736 160 608 160
    WIRE 832 160 736 160
    WIRE 512 192 512 48
    WIRE 592 192 592 160
    WIRE 48 224 48 208
    WIRE -464 256 -544 256
    WIRE -400 256 -464 256
    WIRE -80 272 -80 160
    WIRE 16 272 -80 272
    WIRE 224 272 16 272
    WIRE 304 272 288 272
    WIRE 448 272 448 96
    WIRE 448 272 384 272
    WIRE -80 288 -80 272
    WIRE 16 288 16 272
    WIRE 736 288 720 288
    WIRE 832 288 816 288
    WIRE 912 288 896 288
    WIRE -544 304 -544 256
    WIRE 512 304 512 272
    WIRE 592 304 592 272
    WIRE -400 320 -400 256
    WIRE -80 384 -80 368
    WIRE -32 384 -80 384
    WIRE 16 384 16 352
    WIRE 16 384 -32 384
    WIRE 768 400 768 384
    WIRE -32 416 -32 384
    WIRE 592 416 592 368
    WIRE 720 416 720 288
    WIRE 720 416 592 416
    WIRE 736 416 720 416
    WIRE 816 432 800 432
    WIRE 912 432 912 288
    WIRE 912 432 896 432
    WIRE 448 448 352 448
    WIRE 512 448 512 368
    WIRE 512 448 448 448
    WIRE 736 448 512 448
    WIRE -544 480 -544 384
    WIRE -544 480 -624 480
    WIRE 592 480 592 416
    WIRE 592 480 512 480
    WIRE 768 480 768 464
    WIRE -624 496 -624 480
    WIRE -544 496 -544 480
    WIRE -400 496 -400 384
    WIRE -400 496 -544 496
    WIRE 352 512 352 448
    WIRE 512 512 512 480
    WIRE 448 528 448 448
    WIRE 592 528 592 480
    WIRE -544 576 -544 496
    WIRE 912 576 912 432
    WIRE -400 592 -400 496
    WIRE 352 624 352 592
    WIRE 448 624 448 592
    WIRE 448 624 352 624
    WIRE 512 624 512 592
    WIRE 512 624 448 624
    WIRE 592 624 592 592
    WIRE 592 624 512 624
    WIRE 352 656 352 624
    WIRE -544 752 -544 656
    WIRE -464 752 -544 752
    WIRE -400 752 -400 656
    WIRE -400 752 -464 752
    WIRE -288 752 -288 -128
    WIRE 400 752 -288 752
    WIRE 512 752 400 752
    WIRE 624 752 512 752
    WIRE 736 752 624 752
    WIRE 832 752 736 752
    WIRE 912 752 912 656
    WIRE 912 752 832 752
    WIRE 400 800 400 752
    WIRE 512 800 512 752
    WIRE 624 800 624 752
    WIRE 736 800 736 752
    WIRE 832 800 832 752
    WIRE 912 800 912 752
    WIRE 400 912 400 864
    WIRE 512 912 512 864
    WIRE 624 912 624 864
    WIRE 736 912 736 864
    WIRE 832 912 832 864
    WIRE 912 912 912 864
    FLAG -624 496 0
    FLAG 768 384 V+
    FLAG 48 224 V-
    FLAG -464 256 V+
    FLAG -464 752 V-
    FLAG -32 416 0
    FLAG 736 160 output
    FLAG 48 32 V+
    FLAG 768 480 V-
    FLAG 352 656 0
    FLAG 320 -432 0
    FLAG 912 912 0
    FLAG 832 912 0
    FLAG 736 912 0
    FLAG 624 912 0
    FLAG 512 912 0
    FLAG 400 912 0
    SYMBOL voltage -544 288 R0
    WINDOW 123 0 0 Left 0
    WINDOW 39 10 135 Left 2
    WINDOW 0 12 7 Left 2
    WINDOW 3 15 104 Left 2
    SYMATTR SpiceLine Rser=0.01
    SYMATTR InstName V1
    SYMATTR Value 6
    SYMBOL res 400 256 R90
    WINDOW 0 -7 54 VBottom 2
    WINDOW 3 37 50 VTop 2
    SYMATTR InstName R1
    SYMATTR Value 10.5k
    SYMBOL cap 288 256 R90
    WINDOW 0 0 32 VBottom 2
    WINDOW 3 32 32 VTop 2
    SYMATTR InstName C1
    SYMATTR Value 15n
    SYMBOL cap 32 352 R180
    WINDOW 0 -33 54 Left 2
    WINDOW 3 -49 18 Left 2
    SYMATTR InstName C2
    SYMATTR Value 15n
    SYMBOL polcap -416 320 R0
    SYMATTR InstName C4
    SYMATTR Value 100µ
    SYMBOL res 272 -144 R90
    WINDOW 0 -1 46 VBottom 2
    WINDOW 3 35 56 VTop 2
    SYMATTR InstName R7
    SYMATTR Value 6.34k
    SYMBOL res 416 -144 R90
    WINDOW 0 -4 61 VBottom 2
    WINDOW 3 39 55 VTop 2
    SYMATTR InstName R8
    SYMATTR Value 13k
    SYMBOL njf -112 -176 R90
    WINDOW 0 -37 23 VRight 2
    WINDOW 3 -9 -3 VRight 2
    SYMATTR InstName J1
    SYMATTR Value J112
    SYMBOL voltage -544 560 R0
    WINDOW 123 0 0 Left 0
    WINDOW 39 10 135 Left 2
    WINDOW 0 10 0 Left 2
    WINDOW 3 15 104 Left 2
    SYMATTR SpiceLine Rser=0.01
    SYMATTR InstName V2
    SYMATTR Value 6
    SYMBOL polcap -416 592 R0
    SYMATTR InstName C5
    SYMATTR Value 100µ
    SYMBOL res -96 272 R0
    SYMATTR InstName R2
    SYMATTR Value 10.5k
    SYMBOL res 496 -240 R0
    SYMATTR InstName R9
    SYMATTR Value 4.7
    SYMBOL pjf -112 -544 R90
    WINDOW 0 -34 29 VRight 2
    WINDOW 3 -9 -1 VRight 2
    SYMATTR InstName J2
    SYMATTR Value J175
    SYMBOL schottky 464 -720 R90
    WINDOW 0 0 32 VBottom 2
    WINDOW 3 32 32 VTop 2
    SYMATTR InstName D3
    SYMATTR Value BAS40HY
    SYMATTR Description Diode
    SYMATTR Type diode
    SYMBOL schottky 416 -240 R270
    WINDOW 0 32 32 VTop 2
    WINDOW 3 0 32 VBottom 2
    SYMATTR InstName D5
    SYMATTR Value BAS40HY
    SYMATTR Description Diode
    SYMATTR Type diode
    SYMBOL schottky 464 -640 R90
    WINDOW 0 0 32 VBottom 2
    WINDOW 3 32 32 VTop 2
    SYMATTR InstName D2
    SYMATTR Value BAS40HY
    SYMATTR Description Diode
    SYMATTR Type diode
    SYMBOL schottky 416 -320 R270
    WINDOW 0 32 32 VTop 2
    WINDOW 3 0 32 VBottom 2
    SYMATTR InstName D1
    SYMATTR Value BAS40HY
    SYMATTR Description Diode
    SYMATTR Type diode
    SYMBOL res -96 -384 R90
    WINDOW 0 0 56 VBottom 2
    WINDOW 3 32 56 VTop 2
    SYMATTR InstName R3
    SYMATTR Value 68
    SYMBOL OpAmps\\LT1994 80 128 R0
    WINDOW 3 10 -65 Left 2
    WINDOW 0 11 -95 Left 2
    SYMATTR InstName U2
    SYMBOL OpAmps\\LT1057 768 368 R0
    WINDOW 0 19 104 Left 2
    WINDOW 3 18 130 Left 2
    SYMATTR InstName U1
    SYMBOL schottky 496 304 R0
    WINDOW 3 53 -28 VRight 2
    WINDOW 0 53 91 VRight 2
    SYMATTR Value BAS40HY
    SYMATTR InstName D4
    SYMATTR Description Diode
    SYMATTR Type diode
    SYMBOL schottky 576 304 R0
    WINDOW 3 50 -51 VRight 2
    WINDOW 0 48 74 VRight 2
    SYMATTR Value BAS40HY
    SYMATTR InstName D6
    SYMATTR Description Diode
    SYMATTR Type diode
    SYMBOL cap 432 528 R0
    SYMATTR InstName C7
    SYMATTR Value 10µ
    SYMATTR SpiceLine V=6.3 Irms=0 Rser=0.001 Lser=0 mfg="TDK" pn="C3216X5ROJ106M" type="X5R"
    SYMBOL res 336 496 R0
    SYMATTR InstName R11
    SYMATTR Value 220k
    SYMBOL res 496 496 R0
    WINDOW 3 29 83 Left 2
    SYMATTR Value 220k
    SYMATTR InstName R12
    SYMBOL res 224 -608 R0
    WINDOW 0 -62 49 Left 2
    WINDOW 3 -66 84 Left 2
    SYMATTR InstName R13
    SYMATTR Value 100k
    SYMBOL cap 320 -576 R0
    WINDOW 0 -31 5 Left 2
    WINDOW 3 -36 50 Left 2
    SYMATTR InstName C6
    SYMATTR Value 22µ
    SYMATTR SpiceLine V=6.3 Irms=0 Rser=0.0028 Lser=544p mfg="Würth Elektronik" pn="885012107005 WCAP-CSGP 0805" type="X5R"
    SYMBOL res -96 -624 R0
    WINDOW 0 36 45 Left 2
    WINDOW 3 33 76 Left 2
    SYMATTR InstName R4
    SYMATTR Value 100k
    SYMBOL res -96 -240 R0
    WINDOW 0 36 45 Left 2
    WINDOW 3 34 76 Left 2
    SYMATTR InstName R6
    SYMATTR Value 100k
    SYMBOL res 224 -640 R90
    WINDOW 0 0 56 VBottom 2
    WINDOW 3 32 56 VTop 2
    SYMATTR InstName R14
    SYMATTR Value 100k
    SYMBOL res 240 -272 R90
    WINDOW 0 0 56 VBottom 2
    WINDOW 3 32 56 VTop 2
    SYMATTR InstName R15
    SYMATTR Value 100k
    SYMBOL res 224 -384 R0
    WINDOW 0 -53 15 Left 2
    WINDOW 3 -61 47 Left 2
    SYMATTR InstName R17
    SYMATTR Value 100k
    SYMBOL cap 576 528 R0
    SYMATTR InstName C8
    SYMATTR Value 10µ
    SYMATTR SpiceLine V=6.3 Irms=0 Rser=0.001 Lser=0 mfg="TDK" pn="C3216X5ROJ106M" type="X5R"
    SYMBOL res 416 -32 R90
    WINDOW 0 -4 61 VBottom 2
    WINDOW 3 39 55 VTop 2
    SYMATTR InstName R5
    SYMATTR Value 680k
    SYMBOL res 592 -240 R0
    SYMATTR InstName R10
    SYMATTR Value 4.7
    SYMBOL res 112 -640 R90
    WINDOW 0 0 56 VBottom 2
    WINDOW 3 32 56 VTop 2
    SYMATTR InstName R19
    SYMATTR Value 100k
    SYMBOL res 112 -272 R90
    WINDOW 0 0 56 VBottom 2
    WINDOW 3 32 56 VTop 2
    SYMATTR InstName R20
    SYMATTR Value 100k
    SYMBOL res 896 560 R0
    SYMATTR InstName R16
    SYMATTR Value 100k
    SYMBOL cap 896 800 R0
    SYMATTR InstName C10
    SYMATTR Value 100µ
    SYMATTR SpiceLine V=6.3 Irms=0 Rser=0.002 Lser=0 mfg="TDK" pn="C575OX5ROJI07M" type="X5R"
    SYMBOL cap 816 800 R0
    SYMATTR InstName C12
    SYMATTR Value 100µ
    SYMATTR SpiceLine V=6.3 Irms=0 Rser=0.002 Lser=0 mfg="TDK" pn="C575OX5ROJI07M" type="X5R"
    SYMBOL cap 720 800 R0
    SYMATTR InstName C13
    SYMATTR Value 100µ
    SYMATTR SpiceLine V=6.3 Irms=0 Rser=0.002 Lser=0 mfg="TDK" pn="C575OX5ROJI07M" type="X5R"
    SYMBOL cap 896 272 R90
    WINDOW 0 0 32 VBottom 2
    WINDOW 3 32 32 VTop 2
    SYMATTR InstName C9
    SYMATTR Value 10µ
    SYMATTR SpiceLine V=16 Irms=0 Rser=0 Lser=0 mfg="Murata" pn="GRM188R61C106KAAL" type="X5R"
    SYMBOL res 832 272 R90
    WINDOW 0 0 56 VBottom 2
    WINDOW 3 32 56 VTop 2
    SYMATTR InstName R18
    SYMATTR Value 220
    SYMBOL cap 96 -464 R0
    SYMATTR InstName C15
    SYMATTR Value 1µ
    SYMATTR SpiceLine V=16 Irms=0 Rser=0.007 Lser=0 mfg="TDK" pn="C3216X7RIC105K" type="X7R"
    SYMBOL cap 608 800 R0
    SYMATTR InstName C11
    SYMATTR Value 10µ
    SYMATTR SpiceLine V=6.3 Irms=0 Rser=0.001 Lser=0 mfg="TDK" pn="C3216X5ROJ106M" type="X5R"
    SYMBOL cap 496 800 R0
    SYMATTR InstName C14
    SYMATTR Value 10µ
    SYMATTR SpiceLine V=6.3 Irms=0 Rser=0.001 Lser=0 mfg="TDK" pn="C3216X5ROJ106M" type="X5R"
    SYMBOL cap 384 800 R0
    SYMATTR InstName C16
    SYMATTR Value 10µ
    SYMATTR SpiceLine V=6.3 Irms=0 Rser=0.001 Lser=0 mfg="TDK" pn="C3216X5ROJ106M" type="X5R"
    SYMBOL res 496 176 R0
    WINDOW 0 36 27 Left 2
    WINDOW 3 39 52 Left 2
    SYMATTR InstName R21
    SYMATTR Value 4.7
    SYMBOL res 576 176 R0
    WINDOW 0 38 27 Left 2
    WINDOW 3 40 51 Left 2
    SYMATTR InstName R22
    SYMATTR Value 4.7
    SYMBOL res 912 416 R90
    WINDOW 0 0 56 VBottom 2
    WINDOW 3 32 56 VTop 2
    SYMATTR InstName R23
    SYMATTR Value 100
    SYMBOL cap 320 -352 R0
    WINDOW 0 -27 5 Left 2
    WINDOW 3 -35 47 Left 2
    SYMATTR InstName C3
    SYMATTR Value 22µ
    SYMATTR SpiceLine V=6.3 Irms=0 Rser=0.0028 Lser=544p mfg="Würth Elektronik" pn="885012107005 WCAP-CSGP 0805" type="X5R"
    TEXT -584 840 Left 2 !.tran 0 300s 0s startup
    TEXT -400 -720 Left 2 ;Edward Rawde's high purity sinewave oscillator. 3 Nov 2024

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Jan Panteltje@21:1/5 to invalid@invalid.invalid on Mon Nov 4 06:31:26 2024
    On a sunny day (Sun, 3 Nov 2024 23:06:04 -0500) it happened "Edward Rawde" <invalid@invalid.invalid> wrote in <vg9h7b$277o$1@nnrp.usenet.blueworldhosting.com>:

    Simulation isn't fast but if you let it complete and do an FFT on the last 30 seconds, it's 80dB down at all unwanted
    harmonics.
    There do however seem to be unwanted sidebands close in either side of 1KHz >Any suggestions for improvement?

    Publish a circuit diagram.
    Not that hard to make !

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Bill Sloman@21:1/5 to Jan Panteltje on Mon Nov 4 21:10:56 2024
    On 4/11/2024 5:31 pm, Jan Panteltje wrote:
    On a sunny day (Sun, 3 Nov 2024 23:06:04 -0500) it happened "Edward Rawde" <invalid@invalid.invalid> wrote in <vg9h7b$277o$1@nnrp.usenet.blueworldhosting.com>:

    Simulation isn't fast but if you let it complete and do an FFT on the last 30 seconds, it's 80dB down at all unwanted
    harmonics.
    There do however seem to be unwanted sidebands close in either side of 1KHz >> Any suggestions for improvement?

    Publish a circuit diagram.
    Not that hard to make !

    He did. The .asc file is a circuit diagram. I've looked at it and run
    the simulation - if only for 200 seconds rather than 300 seconds.

    The FFT says that sine wave is as good as he claims.

    The circuit diagram doesn't make it clear what it's various parts are
    there to do - it makes sense to group the components in a way that lets somebody looking at the circuit diagram get some feel for what the
    components are doing.

    And it you are using the LT1994 it makes sense to read the data sheet
    carefully enough to notice that the Icom pin 2 should be bypassed with
    at least 100nF to ground.

    https://www.analog.com/media/en/technical-documentation/data-sheets/1994fb.pdf

    John May's circuit makes it clear that the second FET isn't strictly
    necessary. There are cheaper ways of getting rid of the even-order
    harmonics.

    I've managed to dig out the precision, full wave rectifier that I used
    in my circuit, which is a half-wave rectifier to which you add just
    enough of the full sine wave to deliver both halves of the sine wave
    (one of them inverted) at it's output, which calls for a couple 10k 0.1% thin-film precision resistors on a common substrate, which you can buy
    off the shelf.

    --
    Bill Sloman, Sydney

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Edward Rawde@21:1/5 to Jan Panteltje on Mon Nov 4 11:31:01 2024
    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vg9pnu$ekhh$1@solani.org...
    On a sunny day (Sun, 3 Nov 2024 23:06:04 -0500) it happened "Edward Rawde" <invalid@invalid.invalid> wrote in <vg9h7b$277o$1@nnrp.usenet.blueworldhosting.com>:

    Simulation isn't fast but if you let it complete and do an FFT on the last 30 seconds, it's 80dB down at all unwanted
    harmonics.
    There do however seem to be unwanted sidebands close in either side of 1KHz >>Any suggestions for improvement?

    Publish a circuit diagram.
    Not that hard to make !

    If you mean ASCII art, no thanks in the case of this circuit.

    Assuming Windows, Download this:

    https://notepad-plus-plus.org/downloads/v8.7/

    Yes Windows is crap but you still need the right tools for the job.

    Make a something.asc file (You'll need file extensions turned on) and open it with notepad++
    Paste the contents of my post.
    The second file I posted has the best performance.

    The first and last lines are shown here:
    Version 4
    (many other lines)
    TEXT -400 -720 Left 2 ;Edward Rawde's high purity sinewave oscillator. 3 Nov 2024 V2

    Now check that all lines except the first begin with a word in capital letters. If not then it's likely that line wraps need to be corrected.

    Go to Encoding and choose "Convert to ANSI".
    Save the file.

    Download this: https://www.analog.com/en/resources/design-tools-and-calculators/ltspice-simulator.html

    After installing it make sure it's fully up to date in Tools, Update components and Help Check for updates.

    Close it and open the asc file which should now open with LTSpice.

    Press the green Run/Pause button and another window should open.
    Click in the schematic where it says output and watch the output as it simulates.

    After a while you can select a clean part of the trace and right click to choose View then FFT.
    Select "use current zoom extent and run the FFT".

    Now you can turn your lab into a bedroom or livingroom or something useful.

    To answer Bill's comments, I do read data sheets in detail and I was aware that I should have added an 0.1uF but I just hadn't got
    to it due to the excitement of getting below 80dB :)

    If I was going to build this I'd read the data sheet in a lot more detail because that may turn up other parameters which matter in
    reality such as maximum supply voltage.
    It seems that you're not supposed to go over 5V these days.

    It's not possible to count the number of circuit diagrams I've seen where there was a part or subcircuit and no-one had a clue what
    it was doing.

    The feedback system through U1 seems to be necessary to keep all four diodes making equal contribution all the time.
    Otherwise it can slip into only two diode mode and distortion increases.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Edward Rawde@21:1/5 to Bill Sloman on Mon Nov 4 11:46:40 2024
    "Bill Sloman" <bill.sloman@ieee.org> wrote in message news:vga6jh$suru$1@dont-email.me...
    On 4/11/2024 5:31 pm, Jan Panteltje wrote:
    On a sunny day (Sun, 3 Nov 2024 23:06:04 -0500) it happened "Edward Rawde" >> <invalid@invalid.invalid> wrote in
    <vg9h7b$277o$1@nnrp.usenet.blueworldhosting.com>:

    Simulation isn't fast but if you let it complete and do an FFT on the last 30 seconds, it's 80dB down at all unwanted
    harmonics.
    There do however seem to be unwanted sidebands close in either side of 1KHz >>> Any suggestions for improvement?

    Publish a circuit diagram.
    Not that hard to make !

    He did. The .asc file is a circuit diagram. I've looked at it and run the simulation - if only for 200 seconds rather than 300
    seconds.

    The FFT says that sine wave is as good as he claims.

    The circuit diagram doesn't make it clear what it's various parts are there to do - it makes sense to group the components in a
    way that lets somebody looking at the circuit diagram get some feel for what the components are doing.

    And it you are using the LT1994 it makes sense to read the data sheet carefully enough to notice that the Icom pin 2 should be
    bypassed with at least 100nF to ground.

    https://www.analog.com/media/en/technical-documentation/data-sheets/1994fb.pdf

    Yes there's no way I would use a part without reading the data sheet.
    Pass 1 fount the 0.1uF but I hadn't got around to adding it.
    Pass 2 found that I couldn't go above +/- 6V
    Pass 3 which I haven't done yet would take a lot more time and I probably won't do it because I doubt I'll be able to build this for
    real.

    Please see also my reply to Jan.


    John May's circuit makes it clear that the second FET isn't strictly necessary. There are cheaper ways of getting rid of the
    even-order harmonics.

    Does his circuit have better performance?
    Just curious, it's not a competition.


    I've managed to dig out the precision, full wave rectifier that I used in my circuit, which is a half-wave rectifier to which you
    add just enough of the full sine wave to deliver both halves of the sine wave (one of them inverted) at it's output, which calls
    for a couple 10k 0.1% thin-film precision resistors on a common substrate, which you can buy off the shelf.

    --
    Bill Sloman, Sydney


    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Bill Sloman@21:1/5 to Edward Rawde on Tue Nov 5 13:17:23 2024
    On 5/11/2024 3:46 am, Edward Rawde wrote:
    "Bill Sloman" <bill.sloman@ieee.org> wrote in message news:vga6jh$suru$1@dont-email.me...
    On 4/11/2024 5:31 pm, Jan Panteltje wrote:
    On a sunny day (Sun, 3 Nov 2024 23:06:04 -0500) it happened "Edward Rawde" >>> <invalid@invalid.invalid> wrote in
    <vg9h7b$277o$1@nnrp.usenet.blueworldhosting.com>:

    Simulation isn't fast but if you let it complete and do an FFT on the last 30 seconds, it's 80dB down at all unwanted
    harmonics.
    There do however seem to be unwanted sidebands close in either side of 1KHz
    Any suggestions for improvement?

    Publish a circuit diagram.
    Not that hard to make !

    He did. The .asc file is a circuit diagram. I've looked at it and run the simulation - if only for 200 seconds rather than 300
    seconds.

    The FFT says that sine wave is as good as he claims.

    The circuit diagram doesn't make it clear what it's various parts are there to do - it makes sense to group the components in a
    way that lets somebody looking at the circuit diagram get some feel for what the components are doing.

    And it you are using the LT1994 it makes sense to read the data sheet carefully enough to notice that the Icom pin 2 should be
    bypassed with at least 100nF to ground.

    https://www.analog.com/media/en/technical-documentation/data-sheets/1994fb.pdf

    Yes there's no way I would use a part without reading the data sheet.
    Pass 1 fount the 0.1uF but I hadn't got around to adding it.
    Pass 2 found that I couldn't go above +/- 6V
    Pass 3 which I haven't done yet would take a lot more time and I probably won't do it because I doubt I'll be able to build this for
    real.

    Please see also my reply to Jan.


    John May's circuit makes it clear that the second FET isn't strictly necessary. There are cheaper ways of getting rid of the
    even-order harmonics.

    Does his circuit have better performance?

    The version I got privately certainly did.

    Just curious, it's not a competition.

    Actually, I've decided that the second FET is a bad idea. Two different
    FETs need two different gate drive voltages to give the right channel resistance, and the only guide you've got to that is the amplitude of
    the single sine wave you are producing. A large number of different
    pairs of FET gate drive voltages could give you the same stable amplitude.

    If you monitored the second harmonic component of the output you would
    have a second independent output which could let you optimise both gate
    dries at the same time, but that would be an unnecessary refinement.

    I've managed to dig out the precision, full wave rectifier that I used in my circuit, which is a half-wave rectifier to which you
    add just enough of the full sine wave to deliver both halves of the sine wave (one of them inverted) at it's output, which calls
    for a couple 10k 0.1% thin-film precision resistors on a common substrate, which you can buy off the shelf.

    --
    Bill Sloman, Sydney

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Jan Panteltje@21:1/5 to invalid@invalid.invalid on Tue Nov 5 06:12:05 2024
    On a sunny day (Mon, 4 Nov 2024 11:31:01 -0500) it happened "Edward Rawde" <invalid@invalid.invalid> wrote in <vgass6$28u2$1@nnrp.usenet.blueworldhosting.com>:

    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vg9pnu$ekhh$1@solani.org...
    On a sunny day (Sun, 3 Nov 2024 23:06:04 -0500) it happened "Edward Rawde" >> <invalid@invalid.invalid> wrote in
    <vg9h7b$277o$1@nnrp.usenet.blueworldhosting.com>:

    Simulation isn't fast but if you let it complete and do an FFT on the last 30 seconds, it's 80dB down at all unwanted
    harmonics.
    There do however seem to be unwanted sidebands close in either side of 1KHz >>>Any suggestions for improvement?

    Publish a circuit diagram.
    Not that hard to make !

    If you mean ASCII art, no thanks in the case of this circuit.

    Easy to make a screen shot of your spice circuit and upload it one of those free image publication sites

    You do not seriously expect readers to start ancient peesees and use millisoft widows emulators to run tea spices
    https://panteltje.nl/panteltje/scope_tv/diagram.jpg
    https://panteltje.nl/pub/swr_bridge_hl_lt_spice.gif

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Edward Rawde@21:1/5 to Jan Panteltje on Tue Nov 5 11:00:42 2024
    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vgccvm$6jk3$1@solani.org...
    On a sunny day (Mon, 4 Nov 2024 11:31:01 -0500) it happened "Edward Rawde" <invalid@invalid.invalid> wrote in <vgass6$28u2$1@nnrp.usenet.blueworldhosting.com>:

    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vg9pnu$ekhh$1@solani.org...
    On a sunny day (Sun, 3 Nov 2024 23:06:04 -0500) it happened "Edward Rawde" >>> <invalid@invalid.invalid> wrote in
    <vg9h7b$277o$1@nnrp.usenet.blueworldhosting.com>:

    Simulation isn't fast but if you let it complete and do an FFT on the last 30 seconds, it's 80dB down at all unwanted
    harmonics.
    There do however seem to be unwanted sidebands close in either side of 1KHz >>>>Any suggestions for improvement?

    Publish a circuit diagram.
    Not that hard to make !

    If you mean ASCII art, no thanks in the case of this circuit.

    Easy to make a screen shot of your spice circuit and upload it one of those free image publication sites

    You do not seriously expect readers to start ancient peesees and use millisoft widows emulators to run tea spices
    https://panteltje.nl/panteltje/scope_tv/diagram.jpg https://panteltje.nl/pub/swr_bridge_hl_lt_spice.gif


    These appear to be LTSpice, so why can't you use it to view my circuits?

    In any case if you can't simulate my circuits you won't be able to appreciate how brilliant a designer I am like Bill does.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Edward Rawde@21:1/5 to Bill Sloman on Tue Nov 5 21:39:44 2024
    "Bill Sloman" <bill.sloman@ieee.org> wrote in message news:vgbv7l$177js$3@dont-email.me...
    On 5/11/2024 3:46 am, Edward Rawde wrote:
    "Bill Sloman" <bill.sloman@ieee.org> wrote in message news:vga6jh$suru$1@dont-email.me...
    On 4/11/2024 5:31 pm, Jan Panteltje wrote:
    On a sunny day (Sun, 3 Nov 2024 23:06:04 -0500) it happened "Edward Rawde" >>>> <invalid@invalid.invalid> wrote in
    <vg9h7b$277o$1@nnrp.usenet.blueworldhosting.com>:

    Simulation isn't fast but if you let it complete and do an FFT on the last 30 seconds, it's 80dB down at all unwanted
    harmonics.
    There do however seem to be unwanted sidebands close in either side of 1KHz
    Any suggestions for improvement?

    Publish a circuit diagram.
    Not that hard to make !

    He did. The .asc file is a circuit diagram. I've looked at it and run the simulation - if only for 200 seconds rather than 300
    seconds.

    The FFT says that sine wave is as good as he claims.

    The circuit diagram doesn't make it clear what it's various parts are there to do - it makes sense to group the components in a
    way that lets somebody looking at the circuit diagram get some feel for what the components are doing.

    And it you are using the LT1994 it makes sense to read the data sheet carefully enough to notice that the Icom pin 2 should be
    bypassed with at least 100nF to ground.

    https://www.analog.com/media/en/technical-documentation/data-sheets/1994fb.pdf

    Yes there's no way I would use a part without reading the data sheet.
    Pass 1 fount the 0.1uF but I hadn't got around to adding it.
    Pass 2 found that I couldn't go above +/- 6V
    Pass 3 which I haven't done yet would take a lot more time and I probably won't do it because I doubt I'll be able to build this
    for
    real.

    Please see also my reply to Jan.


    John May's circuit makes it clear that the second FET isn't strictly necessary. There are cheaper ways of getting rid of the
    even-order harmonics.

    Does his circuit have better performance?

    The version I got privately certainly did.

    Just curious, it's not a competition.

    Actually, I've decided that the second FET is a bad idea. Two different FETs need two different gate drive voltages to give the
    right channel resistance, and the only guide you've got to that is the amplitude of the single sine wave you are producing. A
    large number of different pairs of FET gate drive voltages could give you the same stable amplitude.

    If you monitored the second harmonic component of the output you would have a second independent output which could let you
    optimise both gate dries at the same time, but that would be an unnecessary refinement.


    Now approacing 90dB if you believe the simulation with with this experimental circuit.
    You'll want to find something else to do while it simulates.
    How to inprove it further?

    Version 4
    SHEET 1 2196 932
    WIRE -160 -752 -208 -752
    WIRE 16 -752 -80 -752
    WIRE 128 -752 16 -752
    WIRE 288 -752 208 -752
    WIRE -208 -688 -208 -752
    WIRE -128 -688 -208 -688
    WIRE 80 -688 -64 -688
    WIRE 128 -688 80 -688
    WIRE 288 -688 288 -752
    WIRE 288 -688 192 -688
    WIRE 80 -656 80 -688
    WIRE 16 -640 16 -752
    WIRE 16 -544 16 -576
    WIRE 80 -544 80 -576
    WIRE 16 -464 16 -480
    WIRE 80 -448 48 -448
    WIRE 288 -448 288 -688
    WIRE 288 -448 80 -448
    WIRE -208 -432 -208 -688
    WIRE -16 -432 -208 -432
    WIRE 192 -416 48 -416
    WIRE 240 -416 192 -416
    WIRE 368 -416 320 -416
    WIRE 432 -416 368 -416
    WIRE 512 -416 432 -416
    WIRE 624 -416 512 -416
    WIRE -208 -384 -208 -432
    WIRE 16 -384 16 -400
    WIRE 368 -368 368 -416
    WIRE 80 -352 80 -448
    WIRE 192 -352 192 -416
    WIRE 432 -352 432 -416
    WIRE 512 -352 512 -416
    WIRE 624 -352 624 -416
    WIRE -208 -272 -208 -304
    WIRE -208 -272 -304 -272
    WIRE -208 -240 -208 -272
    WIRE 80 -240 80 -272
    WIRE 192 -240 192 -288
    WIRE 432 -240 432 -288
    WIRE 512 -224 512 -288
    WIRE 624 -224 624 -288
    WIRE 368 -192 368 -288
    WIRE 368 -192 -16 -192
    WIRE -304 -176 -304 -272
    WIRE -336 -128 -368 -128
    WIRE -208 -128 -208 -160
    WIRE -208 -128 -240 -128
    WIRE -192 -128 -208 -128
    WIRE 144 -128 -192 -128
    WIRE 288 -128 224 -128
    WIRE 352 -128 288 -128
    WIRE 512 -128 512 -144
    WIRE 512 -128 432 -128
    WIRE -368 -48 -368 -128
    WIRE -320 -48 -368 -48
    WIRE -192 -48 -192 -128
    WIRE -192 -48 -240 -48
    WIRE 288 -16 288 -128
    WIRE 288 -16 64 -16
    WIRE 352 -16 288 -16
    WIRE 512 -16 512 -128
    WIRE 512 -16 432 -16
    WIRE -368 0 -368 -48
    WIRE 144 48 144 32
    WIRE 64 96 64 -16
    WIRE 112 96 64 96
    WIRE 512 96 512 -16
    WIRE 512 96 272 96
    WIRE -32 128 -112 128
    WIRE -16 128 -16 -192
    WIRE -16 128 -32 128
    WIRE 112 128 -16 128
    WIRE -336 144 -416 144
    WIRE -272 144 -336 144
    WIRE 624 144 624 -144
    WIRE 656 144 624 144
    WIRE 768 144 720 144
    WIRE 848 144 768 144
    WIRE -112 160 -112 128
    WIRE 112 160 64 160
    WIRE 624 160 624 144
    WIRE 624 160 272 160
    WIRE -416 192 -416 144
    WIRE -272 208 -272 144
    WIRE 144 224 144 208
    WIRE 848 240 848 144
    WIRE -112 256 -112 224
    WIRE 64 272 64 160
    WIRE 160 272 64 272
    WIRE 256 272 160 272
    WIRE 352 272 320 272
    WIRE 512 272 512 96
    WIRE 512 272 432 272
    WIRE 64 288 64 272
    WIRE 160 288 160 272
    WIRE 512 320 512 272
    WIRE 624 320 624 160
    WIRE -416 368 -416 272
    WIRE -416 368 -496 368
    WIRE -496 384 -496 368
    WIRE -416 384 -416 368
    WIRE -272 384 -272 272
    WIRE -272 384 -416 384
    WIRE 64 384 64 368
    WIRE 160 384 160 352
    WIRE 160 384 64 384
    WIRE 64 416 64 384
    WIRE 848 416 848 320
    WIRE -32 448 -32 128
    WIRE -416 464 -416 384
    WIRE 144 464 96 464
    WIRE 256 464 224 464
    WIRE 368 464 320 464
    WIRE -272 480 -272 384
    WIRE 512 480 512 400
    WIRE 624 480 624 400
    WIRE 288 576 288 560
    WIRE 368 592 368 464
    WIRE 368 592 320 592
    WIRE 624 592 624 544
    WIRE 624 592 368 592
    WIRE -32 608 -32 528
    WIRE 32 608 -32 608
    WIRE 96 608 96 464
    WIRE 96 608 32 608
    WIRE 144 608 96 608
    WIRE 256 608 224 608
    WIRE 432 624 320 624
    WIRE 512 624 512 544
    WIRE 512 624 432 624
    WIRE 624 624 624 592
    WIRE 704 624 624 624
    WIRE -416 640 -416 544
    WIRE -336 640 -416 640
    WIRE -272 640 -272 544
    WIRE -272 640 -336 640
    WIRE 288 656 288 640
    WIRE 512 688 512 624
    WIRE 704 688 704 624
    WIRE 432 704 432 624
    WIRE 624 704 624 624
    WIRE 432 800 432 768
    WIRE 512 800 512 768
    WIRE 512 800 432 800
    WIRE 624 800 624 768
    WIRE 624 800 512 800
    WIRE 704 800 704 768
    WIRE 704 800 624 800
    WIRE 432 832 432 800
    FLAG -496 384 0
    FLAG 288 560 V+
    FLAG 144 224 V-
    FLAG -336 144 V+
    FLAG -336 640 V-
    FLAG 768 144 output
    FLAG 144 32 V+
    FLAG 288 656 V-
    FLAG 432 832 0
    FLAG -112 256 0
    FLAG 32 608 dc-trim
    FLAG 16 -480 V+
    FLAG 16 -384 V-
    FLAG -368 0 0
    FLAG 432 -240 0
    FLAG 192 -240 0
    FLAG 848 416 0
    FLAG 64 416 0
    FLAG 80 -240 0
    FLAG 16 -544 0
    FLAG 80 -544 0
    SYMBOL voltage -416 176 R0
    WINDOW 123 0 0 Left 0
    WINDOW 39 10 135 Left 2
    WINDOW 0 12 7 Left 2
    WINDOW 3 15 104 Left 2
    SYMATTR SpiceLine Rser=0.01
    SYMATTR InstName V1
    SYMATTR Value 6
    SYMBOL res 448 256 R90
    WINDOW 0 -7 54 VBottom 2
    WINDOW 3 37 50 VTop 2
    SYMATTR InstName R1
    SYMATTR Value 10.5k
    SYMBOL cap 320 256 R90
    WINDOW 0 0 32 VBottom 2
    WINDOW 3 32 32 VTop 2
    SYMATTR InstName C1
    SYMATTR Value 0.015µ
    SYMATTR SpiceLine V=16 Irms=271m Rser=0.594318 Lser=0 mfg="KEMET" pn="C0603C153K4RAC" type="X7R"
    SYMBOL res 240 -144 R90
    WINDOW 0 -1 46 VBottom 2
    WINDOW 3 35 56 VTop 2
    SYMATTR InstName R7
    SYMATTR Value 6.34k
    SYMBOL res 448 -144 R90
    WINDOW 0 -4 61 VBottom 2
    WINDOW 3 39 55 VTop 2
    SYMATTR InstName R8
    SYMATTR Value 13k
    SYMBOL njf -240 -176 R90
    WINDOW 0 -37 23 VRight 2
    WINDOW 3 -9 -3 VRight 2
    SYMATTR InstName J1
    SYMATTR Value J112
    SYMBOL voltage -416 448 R0
    WINDOW 123 0 0 Left 0
    WINDOW 39 10 135 Left 2
    WINDOW 0 10 0 Left 2
    WINDOW 3 15 104 Left 2
    SYMATTR SpiceLine Rser=0.01
    SYMATTR InstName V2
    SYMATTR Value 6
    SYMBOL res 48 272 R0
    WINDOW 3 36 65 Left 2
    SYMATTR Value 10.5k
    SYMATTR InstName R2
    SYMBOL res 496 -240 R0
    SYMATTR InstName R9
    SYMATTR Value 4.7
    SYMBOL schottky 496 -352 R0
    WINDOW 3 -17 -1 VRight 2
    SYMATTR Value BAS40HY
    SYMATTR InstName D1
    SYMATTR Description Diode
    SYMATTR Type diode
    SYMBOL schottky 608 -352 R0
    WINDOW 3 -18 1 VRight 2
    SYMATTR Value BAS40HY
    SYMATTR InstName D2
    SYMATTR Description Diode
    SYMATTR Type diode
    SYMBOL res -224 -64 R90
    WINDOW 0 0 56 VBottom 2
    WINDOW 3 32 56 VTop 2
    SYMATTR InstName R3
    SYMATTR Value 82
    SYMBOL OpAmps\\LT1994 176 128 R0
    WINDOW 3 10 -65 Left 2
    WINDOW 0 11 -95 Left 2
    SYMATTR InstName U2
    SYMBOL OpAmps\\LT1057 288 544 M0
    WINDOW 0 19 104 Left 2
    WINDOW 3 18 130 Left 2
    SYMATTR InstName U1
    SYMBOL schottky 528 480 M0
    WINDOW 3 54 -49 VRight 2
    WINDOW 0 -18 3 Left 2
    SYMATTR Value BAS40HY
    SYMATTR InstName D3
    SYMATTR Description Diode
    SYMATTR Type diode
    SYMBOL schottky 640 480 M0
    WINDOW 3 48 -53 VRight 2
    WINDOW 0 -21 4 Left 2
    SYMATTR Value BAS40HY
    SYMATTR InstName D4
    SYMATTR Description Diode
    SYMATTR Type diode
    SYMBOL cap 448 704 M0
    SYMATTR InstName C7
    SYMATTR Value 10µ
    SYMATTR SpiceLine V=6.3 Irms=0 Rser=0.001 Lser=0 mfg="TDK" pn="C3216X5ROJ106M" type="X5R"
    SYMBOL res 528 672 M0
    WINDOW 3 30 83 Left 2
    SYMATTR Value 220k
    SYMATTR InstName R11
    SYMBOL res 720 672 M0
    WINDOW 3 29 83 Left 2
    SYMATTR Value 220k
    SYMATTR InstName R12
    SYMBOL res -224 -256 R0
    WINDOW 0 38 42 Left 2
    WINDOW 3 36 66 Left 2
    SYMATTR InstName R6
    SYMATTR Value 2.2k
    SYMBOL res 224 -400 R270
    WINDOW 0 -29 23 VTop 2
    WINDOW 3 -1 95 VBottom 2
    SYMATTR InstName R15
    SYMATTR Value 330k
    SYMBOL res 352 -384 R0
    WINDOW 0 -57 53 Left 2
    WINDOW 3 -63 90 Left 2
    SYMATTR InstName R17
    SYMATTR Value 100k
    SYMBOL cap 640 704 M0
    SYMATTR InstName C8
    SYMATTR Value 10µ
    SYMATTR SpiceLine V=6.3 Irms=0 Rser=0.001 Lser=0 mfg="TDK" pn="C3216X5ROJ106M" type="X5R"
    SYMBOL res 448 -32 R90
    WINDOW 0 -4 61 VBottom 2
    WINDOW 3 39 55 VTop 2
    SYMATTR InstName R5
    SYMATTR Value 1.095Meg
    SYMBOL res 608 -240 R0
    SYMATTR InstName R10
    SYMATTR Value 4.7
    SYMBOL res -192 -288 R180
    WINDOW 0 40 70 Left 2
    WINDOW 3 45 42 Left 2
    SYMATTR InstName R20
    SYMATTR Value 2.2k
    SYMBOL res -16 544 R180
    WINDOW 0 36 76 Left 2
    WINDOW 3 36 40 Left 2
    SYMATTR InstName R16
    SYMATTR Value 47k
    SYMBOL res 128 448 M90
    WINDOW 0 0 56 VBottom 2
    WINDOW 3 32 56 VTop 2
    SYMATTR InstName R18
    SYMATTR Value 220
    SYMBOL res 528 304 M0
    WINDOW 0 36 27 Left 2
    WINDOW 3 39 52 Left 2
    SYMATTR InstName R21
    SYMATTR Value 4.7
    SYMBOL res 640 304 M0
    WINDOW 0 38 27 Left 2
    WINDOW 3 40 51 Left 2
    SYMATTR InstName R22
    SYMATTR Value 4.7
    SYMBOL res 128 592 M90
    WINDOW 0 0 56 VBottom 2
    WINDOW 3 32 56 VTop 2
    SYMATTR InstName R23
    SYMATTR Value 100
    SYMBOL cap 416 -352 R0
    WINDOW 0 -27 5 Left 2
    WINDOW 3 -35 47 Left 2
    SYMATTR InstName C3
    SYMATTR Value 22µ
    SYMATTR SpiceLine V=6.3 Irms=0 Rser=0.0028 Lser=544p mfg="Würth Elektronik" pn="885012107005 WCAP-CSGP 0805" type="X5R"
    SYMBOL cap 176 352 R180
    WINDOW 0 -36 39 Left 2
    WINDOW 3 -86 12 Left 2
    SYMATTR InstName C2
    SYMATTR Value 0.015µ
    SYMATTR SpiceLine V=16 Irms=271m Rser=0.594318 Lser=0 mfg="KEMET" pn="C0603C153K4RAC" type="X7R"
    SYMBOL cap -288 208 R0
    SYMATTR InstName C4
    SYMATTR Value 100µ
    SYMATTR SpiceLine V=6.3 Irms=0 Rser=0.002 Lser=0 mfg="TDK" pn="C575OX5ROJI07M" type="X5R"
    SYMBOL cap -288 480 R0
    SYMATTR InstName C5
    SYMATTR Value 100µ
    SYMATTR SpiceLine V=6.3 Irms=0 Rser=0.002 Lser=0 mfg="TDK" pn="C575OX5ROJI07M" type="X5R"
    SYMBOL cap 256 448 M90
    WINDOW 0 0 32 VBottom 2
    WINDOW 3 32 32 VTop 2
    SYMATTR InstName C9
    SYMATTR Value 10µ
    SYMATTR SpiceLine V=6.3 Irms=0 Rser=0.001 Lser=0 mfg="TDK" pn="C3216X5ROJ106M" type="X5R"
    SYMBOL OpAmps\\LT1057 16 -496 M0
    WINDOW 0 73 93 Left 2
    WINDOW 3 18 119 Left 2
    SYMATTR InstName U3
    SYMBOL cap 720 128 R90
    WINDOW 0 0 32 VBottom 2
    WINDOW 3 32 32 VTop 2
    SYMATTR InstName C6
    SYMATTR Value 1µ
    SYMATTR SpiceLine V=10 Irms=0 Rser=0.0065 Lser=542p mfg="Würth Elektronik" pn="885012208013 WCAP-CSGP 1206" type="X7R"
    SYMBOL res 832 224 R0
    SYMATTR InstName R4
    SYMATTR Value 100k
    SYMBOL cap -128 160 R0
    SYMATTR InstName C10
    SYMATTR Value 1µ
    SYMATTR SpiceLine V=10 Irms=0 Rser=0.0065 Lser=542p mfg="Würth Elektronik" pn="885012208013 WCAP-CSGP 1206" type="X7R"
    SYMBOL res 112 -736 R270
    WINDOW 0 34 21 VTop 2
    WINDOW 3 62 88 VBottom 2
    SYMATTR InstName R13
    SYMATTR Value 22k
    SYMBOL res 64 -368 R0
    SYMATTR InstName R14
    SYMATTR Value 22k
    SYMBOL res -176 -736 R270
    WINDOW 0 34 21 VTop 2
    WINDOW 3 62 88 VBottom 2
    SYMATTR InstName R19
    SYMATTR Value 22k
    SYMBOL res 64 -672 R0
    SYMATTR InstName R24
    SYMATTR Value 10k
    SYMBOL cap -128 -672 R270
    WINDOW 0 32 32 VTop 2
    WINDOW 3 0 32 VBottom 2
    SYMATTR InstName C16
    SYMATTR Value 0.0082µ
    SYMATTR SpiceLine V=25 Irms=0 Rser=0 Lser=0 mfg="Murata" pn="GCM155R71E822JA37" type="X7R"
    SYMBOL cap 32 -576 R180
    WINDOW 0 24 56 Left 2
    WINDOW 3 24 8 Left 2
    SYMATTR InstName C11
    SYMATTR Value 0.015µ
    SYMATTR SpiceLine V=16 Irms=271m Rser=0.594318 Lser=0 mfg="KEMET" pn="C0603C153K4RAC" type="X7R"
    SYMBOL cap 128 -672 R270
    WINDOW 0 32 32 VTop 2
    WINDOW 3 0 32 VBottom 2
    SYMATTR InstName C12
    SYMATTR Value 0.0082µ
    SYMATTR SpiceLine V=25 Irms=0 Rser=0 Lser=0 mfg="Murata" pn="GCM155R71E822JA37" type="X7R"
    SYMBOL cap 176 -352 R0
    WINDOW 0 22 11 Left 2
    WINDOW 3 21 58 Left 2
    SYMATTR InstName C13
    SYMATTR Value 22µ
    SYMATTR SpiceLine V=6.3 Irms=0 Rser=0.0028 Lser=544p mfg="Würth Elektronik" pn="885012107005 WCAP-CSGP 0805" type="X5R"
    TEXT -456 728 Left 2 !.tran 0 300s 0s startup
    TEXT -288 -856 Left 2 ;Edward Rawde's high purity sinewave oscillator. 5 Nov 2024

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Bill Sloman@21:1/5 to Edward Rawde on Wed Nov 6 17:36:56 2024
    On 6/11/2024 3:00 am, Edward Rawde wrote:
    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vgccvm$6jk3$1@solani.org...
    On a sunny day (Mon, 4 Nov 2024 11:31:01 -0500) it happened "Edward Rawde" >> <invalid@invalid.invalid> wrote in
    <vgass6$28u2$1@nnrp.usenet.blueworldhosting.com>:

    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vg9pnu$ekhh$1@solani.org...
    On a sunny day (Sun, 3 Nov 2024 23:06:04 -0500) it happened "Edward Rawde" >>>> <invalid@invalid.invalid> wrote in
    <vg9h7b$277o$1@nnrp.usenet.blueworldhosting.com>:

    Simulation isn't fast but if you let it complete and do an FFT on the last 30 seconds, it's 80dB down at all unwanted
    harmonics.
    There do however seem to be unwanted sidebands close in either side of 1KHz
    Any suggestions for improvement?

    Publish a circuit diagram.
    Not that hard to make !

    If you mean ASCII art, no thanks in the case of this circuit.

    Easy to make a screen shot of your spice circuit and upload it one of those free image publication sites

    You do not seriously expect readers to start ancient peesees and use millisoft widows emulators to run tea spices
    https://panteltje.nl/panteltje/scope_tv/diagram.jpg
    https://panteltje.nl/pub/swr_bridge_hl_lt_spice.gif


    These appear to be LTSpice, so why can't you use it to view my circuits?

    In any case if you can't simulate my circuits you won't be able to appreciate how brilliant a designer I am like Bill does.

    The quantity of brilliance is only apparent when you can see the circuit diagram and work out what he is trying to do, which can take a while.

    --
    Bill Sloman, Sydney



    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Jan Panteltje@21:1/5 to invalid@invalid.invalid on Wed Nov 6 07:07:19 2024
    On a sunny day (Tue, 5 Nov 2024 11:00:42 -0500) it happened "Edward Rawde" <invalid@invalid.invalid> wrote in <vgdffb$ibt$1@nnrp.usenet.blueworldhosting.com>:

    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vgccvm$6jk3$1@solani.org...
    On a sunny day (Mon, 4 Nov 2024 11:31:01 -0500) it happened "Edward Rawde" >> <invalid@invalid.invalid> wrote in
    <vgass6$28u2$1@nnrp.usenet.blueworldhosting.com>:

    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vg9pnu$ekhh$1@solani.org...
    On a sunny day (Sun, 3 Nov 2024 23:06:04 -0500) it happened "Edward Rawde" >>>> <invalid@invalid.invalid> wrote in
    <vg9h7b$277o$1@nnrp.usenet.blueworldhosting.com>:

    Simulation isn't fast but if you let it complete and do an FFT on the last 30 seconds, it's 80dB down at all unwanted
    harmonics.
    There do however seem to be unwanted sidebands close in either side of 1KHz
    Any suggestions for improvement?

    Publish a circuit diagram.
    Not that hard to make !

    If you mean ASCII art, no thanks in the case of this circuit.

    Easy to make a screen shot of your spice circuit and upload it one of those free image publication sites

    You do not seriously expect readers to start ancient peesees and use millisoft widows emulators to run tea spices
    https://panteltje.nl/panteltje/scope_tv/diagram.jpg
    https://panteltje.nl/pub/swr_bridge_hl_lt_spice.gif


    These appear to be LTSpice, so why can't you use it to view my circuits?

    As I pointed out, am reading Usenet on a Raspbeery Pi4 8GB
    Does everything here from spectrum analyzing to audio to video play
    Why boot up an acient peesee to start a millisoft widows emulator
    to look up some 80 deebee thingy that likely never has a practical use?


    In any case if you can't simulate my circuits you won't be able to appreciate how brilliant a designer I am like Bill does.

    80 deebee makes me wonder if you not better spend your time on making e-bikes from vipes...
    com/gadgets/2024/11/disposable-vapes-from-a-music-festival-can-power-a-beefy-e-bike-20-miles/

    And elteasprites simu is not worth a thing, reality is different from the models used
    I stopped using it long ago (years)
    My stuff works.

    ElTeaSprites is a bit like Hollowwood movies.
    Burb .. I mean Kirk.. well
    I do not question your genius,

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Bill Sloman@21:1/5 to Jan Panteltje on Wed Nov 6 20:06:20 2024
    On 6/11/2024 6:07 pm, Jan Panteltje wrote:
    On a sunny day (Tue, 5 Nov 2024 11:00:42 -0500) it happened "Edward Rawde" <invalid@invalid.invalid> wrote in <vgdffb$ibt$1@nnrp.usenet.blueworldhosting.com>:

    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vgccvm$6jk3$1@solani.org...
    On a sunny day (Mon, 4 Nov 2024 11:31:01 -0500) it happened "Edward Rawde" >>> <invalid@invalid.invalid> wrote in
    <vgass6$28u2$1@nnrp.usenet.blueworldhosting.com>:

    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vg9pnu$ekhh$1@solani.org...
    On a sunny day (Sun, 3 Nov 2024 23:06:04 -0500) it happened "Edward Rawde"
    <invalid@invalid.invalid> wrote in
    <vg9h7b$277o$1@nnrp.usenet.blueworldhosting.com>:

    Simulation isn't fast but if you let it complete and do an FFT on the last 30 seconds, it's 80dB down at all unwanted
    harmonics.
    There do however seem to be unwanted sidebands close in either side of 1KHz
    Any suggestions for improvement?

    Publish a circuit diagram.
    Not that hard to make !

    If you mean ASCII art, no thanks in the case of this circuit.

    Easy to make a screen shot of your spice circuit and upload it one of those free image publication sites

    You do not seriously expect readers to start ancient peesees and use millisoft widows emulators to run tea spices
    https://panteltje.nl/panteltje/scope_tv/diagram.jpg
    https://panteltje.nl/pub/swr_bridge_hl_lt_spice.gif


    These appear to be LTSpice, so why can't you use it to view my circuits?

    As I pointed out, am reading Usenet on a Raspbeery Pi4 8GB
    Does everything here from spectrum analyzing to audio to video play
    Why boot up an acient peesee to start a millisoft widows emulator
    to look up some 80 deebee thingy that likely never has a practical use?


    In any case if you can't simulate my circuits you won't be able to appreciate how brilliant a designer I am like Bill does.

    80 deebee makes me wonder if you not better spend your time on making e-bikes from vipes...
    com/gadgets/2024/11/disposable-vapes-from-a-music-festival-can-power-a-beefy-e-bike-20-miles/

    And elteasprites simu is not worth a thing, reality is different from the models used.

    Not all that different, and you can test a new idea in LTSpice a lot
    faster than you can cobble stuff together on the bench.

    I stopped using it long ago (years).
    My stuff works.

    Because you don't try anything new?

    ElTeaSprites is a bit like Hollowwood movies.

    Hollywood movies are expensive. LTSpice is free.

    Burb .. I mean Kirk.. well
    I do not question your genius,

    Sci.electronics.design does seem to be a genius-free space. There are
    quite a few competent people who post here, but genius is rare, and most
    of the people who are called geniuses have exploited a stroke of luck
    that let them look better than they deserve, though as Pasteur said,
    chance does favour the prepared mind.

    Plowing through a lot of circuit variations quickly with LTSpice does
    give you more chances to win that particular lottery.

    --
    Bill Sloman, Sydney

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Jeroen Belleman@21:1/5 to Edward Rawde on Wed Nov 6 10:04:42 2024
    On 11/6/24 03:39, Edward Rawde wrote:
    [Snip!]
    Now approacing 90dB if you believe the simulation with with this experimental circuit.
    You'll want to find something else to do while it simulates.
    How to inprove it further?

    Version 4
    [Deleted....]

    You are chasing ghosts. Simulation doesn't prove anything at this
    level. Build it and measure it.

    Jeroen Belleman

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Jan Panteltje@21:1/5 to jeroen@nospam.please on Wed Nov 6 09:44:06 2024
    On a sunny day (Wed, 6 Nov 2024 10:04:42 +0100) it happened Jeroen Belleman <jeroen@nospam.please> wrote in <vgfb8d$21qub$1@dont-email.me>:

    On 11/6/24 03:39, Edward Rawde wrote:
    [Snip!]
    Now approacing 90dB if you believe the simulation with with this experimental circuit.
    You'll want to find something else to do while it simulates.
    How to inprove it further?

    Version 4
    [Deleted....]

    You are chasing ghosts. Simulation doesn't prove anything at this
    level. Build it and measure it.

    Jeroen Belleman

    +1

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Jan Panteltje@21:1/5 to bill.sloman@ieee.org on Wed Nov 6 09:43:37 2024
    On a sunny day (Wed, 6 Nov 2024 20:06:20 +1100) it happened Bill Sloman <bill.sloman@ieee.org> wrote in <vgfbii$21t2e$1@dont-email.me>:

    On 6/11/2024 6:07 pm, Jan Panteltje wrote:
    On a sunny day (Tue, 5 Nov 2024 11:00:42 -0500) it happened "Edward Rawde" >> <invalid@invalid.invalid> wrote in
    <vgdffb$ibt$1@nnrp.usenet.blueworldhosting.com>:

    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vgccvm$6jk3$1@solani.org...
    On a sunny day (Mon, 4 Nov 2024 11:31:01 -0500) it happened "Edward Rawde" >>>> <invalid@invalid.invalid> wrote in
    <vgass6$28u2$1@nnrp.usenet.blueworldhosting.com>:

    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vg9pnu$ekhh$1@solani.org...
    On a sunny day (Sun, 3 Nov 2024 23:06:04 -0500) it happened "Edward Rawde"
    <invalid@invalid.invalid> wrote in
    <vg9h7b$277o$1@nnrp.usenet.blueworldhosting.com>:

    Simulation isn't fast but if you let it complete and do an FFT on the last 30 seconds, it's 80dB down at all unwanted
    harmonics.
    There do however seem to be unwanted sidebands close in either side of 1KHz
    Any suggestions for improvement?

    Publish a circuit diagram.
    Not that hard to make !

    If you mean ASCII art, no thanks in the case of this circuit.

    Easy to make a screen shot of your spice circuit and upload it one of those free image publication sites

    You do not seriously expect readers to start ancient peesees and use millisoft widows emulators to run tea spices
    https://panteltje.nl/panteltje/scope_tv/diagram.jpg
    https://panteltje.nl/pub/swr_bridge_hl_lt_spice.gif


    These appear to be LTSpice, so why can't you use it to view my circuits?

    As I pointed out, am reading Usenet on a Raspbeery Pi4 8GB
    Does everything here from spectrum analyzing to audio to video play
    Why boot up an acient peesee to start a millisoft widows emulator
    to look up some 80 deebee thingy that likely never has a practical use?


    In any case if you can't simulate my circuits you won't be able to appreciate how brilliant a designer I am like Bill does.

    80 deebee makes me wonder if you not better spend your time on making e-bikes from vipes...
    com/gadgets/2024/11/disposable-vapes-from-a-music-festival-can-power-a-beefy-e-bike-20-miles/

    And elteasprites simu is not worth a thing, reality is different from the models used.

    I sometimes compare the ElTeaSPrites to a mamatician trying to play tennis Fater all the things.. The human neural net plays score after score
    while the mamatician is still simulating the first backhand..

    Bit elated I am as Trump is winning :-)
    Maybe ends the ByeThen war making for money game.



    Not all that different, and you can test a new idea in LTSpice a lot
    faster than you can cobble stuff together on the bench.

    I stopped using it long ago (years).
    My stuff works.

    Because you don't try anything new?

    Very little is 'new'.
    My neural net has been trained on electronics since the early fifties of last century.
    ELTheaSPice is just a word...
    Used it once to check some filter curves, but there are better filter programs It gave the wrong results on a simple amplifier I tried on it.
    It is extremely limited and again compare it to the tennis player that trained a lifetime
    a joke basically.
    Get into the very high frequency domain, did a lot of that stuff, it is then more about layout and wavelength and similar stuff
    how circuits behave.


    ElTeaSprites is a bit like Hollowwood movies.

    Hollywood movies are expensive. LTSpice is free.

    Burb .. I mean Kirk.. well
    I do not question your genius,

    Sci.electronics.design does seem to be a genius-free space.

    It is design, if it works what is cooked up here, great!
    Sure got some interesting ideas from here that I tried.


    There are
    quite a few competent people who post here, but genius is rare, and most
    of the people who are called geniuses have exploited a stroke of luck
    that let them look better than they deserve, though as Pasteur said,
    chance does favour the prepared mind.

    My interests are much wider than electronics
    worked in many fields
    from electronics to TV to power stations to medical to aircraft to satellite ..what not.


    Plowing through a lot of circuit variations quickly with LTSpice does
    give you more chances to win that particular lottery.

    Sounds like gambling...
    these days AI is using that method to try a zillion variation in medicine related creations.
    It may or may not work.
    But _understanding_comes first and is always the winner.
    Lucky shot may help too.

    There is nothing you can not do if you are sufficiently motivated.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Liz Tuddenham@21:1/5 to Jan Panteltje on Wed Nov 6 10:35:12 2024
    Jan Panteltje <alien@comet.invalid> wrote:

    Bit elated I am as Trump is winning :-)
    Maybe ends the ByeThen war making for money game.

    Don't believe anything a politician tells you. That applies to Trump -
    only more so.

    --
    ~ Liz Tuddenham ~
    (Remove the ".invalid"s and add ".co.uk" to reply)
    www.poppyrecords.co.uk

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Jan Panteltje@21:1/5 to Liz Tuddenham on Wed Nov 6 13:30:45 2024
    On a sunny day (Wed, 6 Nov 2024 10:35:12 +0000) it happened liz@poppyrecords.invalid.invalid (Liz Tuddenham) wrote in <1r2ljy1.1n1fa0rx4fz7qN%liz@poppyrecords.invalid.invalid>:

    Jan Panteltje <alien@comet.invalid> wrote:

    Bit elated I am as Trump is winning :-)
    Maybe ends the ByeThen war making for money game.

    Don't believe anything a politician tells you. That applies to Trump -
    only more so.

    He pulled back from Afghanistan!

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Bill Sloman@21:1/5 to Jan Panteltje on Thu Nov 7 01:11:06 2024
    On 6/11/2024 8:43 pm, Jan Panteltje wrote:
    On a sunny day (Wed, 6 Nov 2024 20:06:20 +1100) it happened Bill Sloman <bill.sloman@ieee.org> wrote in <vgfbii$21t2e$1@dont-email.me>:

    On 6/11/2024 6:07 pm, Jan Panteltje wrote:
    On a sunny day (Tue, 5 Nov 2024 11:00:42 -0500) it happened "Edward Rawde" >>> <invalid@invalid.invalid> wrote in
    <vgdffb$ibt$1@nnrp.usenet.blueworldhosting.com>:

    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vgccvm$6jk3$1@solani.org...
    On a sunny day (Mon, 4 Nov 2024 11:31:01 -0500) it happened "Edward Rawde"
    <invalid@invalid.invalid> wrote in
    <vgass6$28u2$1@nnrp.usenet.blueworldhosting.com>:

    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vg9pnu$ekhh$1@solani.org...
    On a sunny day (Sun, 3 Nov 2024 23:06:04 -0500) it happened "Edward Rawde"
    <invalid@invalid.invalid> wrote in
    <vg9h7b$277o$1@nnrp.usenet.blueworldhosting.com>:

    Simulation isn't fast but if you let it complete and do an FFT on the last 30 seconds, it's 80dB down at all unwanted
    harmonics.
    There do however seem to be unwanted sidebands close in either side of 1KHz
    Any suggestions for improvement?

    Publish a circuit diagram.
    Not that hard to make !

    If you mean ASCII art, no thanks in the case of this circuit.

    Easy to make a screen shot of your spice circuit and upload it one of those free image publication sites

    You do not seriously expect readers to start ancient peesees and use millisoft widows emulators to run tea spices
    https://panteltje.nl/panteltje/scope_tv/diagram.jpg
    https://panteltje.nl/pub/swr_bridge_hl_lt_spice.gif


    These appear to be LTSpice, so why can't you use it to view my circuits? >>>
    As I pointed out, am reading Usenet on a Raspbeery Pi4 8GB
    Does everything here from spectrum analyzing to audio to video play
    Why boot up an acient peesee to start a millisoft widows emulator
    to look up some 80 deebee thingy that likely never has a practical use?


    In any case if you can't simulate my circuits you won't be able to appreciate how brilliant a designer I am like Bill does.

    80 deebee makes me wonder if you not better spend your time on making e-bikes from vipes...
    com/gadgets/2024/11/disposable-vapes-from-a-music-festival-can-power-a-beefy-e-bike-20-miles/

    And elteasprites simu is not worth a thing, reality is different from the models used.

    I sometimes compare the ElTeaSPrites to a mathematician trying to play tennis Faster all the things.. The human neural net plays score after score
    while the mathemtician is still simulating the first backhand..

    Not if he's got a decent conmputer to run his simulations.

    Bit elated I am as Trump is winning :-)

    It does look that way. Your elation will fade as he starts implentming
    his silly ideas

    Maybe ends the Biden war making for money game.

    Trump persuaded Putin that he could get away with invading the Ukraine.
    Biden got elected a long time after Putin had started encouraging
    pro-Russian insurrections in the Ukraine, and Trump was impeached for attempting to influence Zelensky by threatening to hold back military
    aid that the then Repulicna dominated US Congress had voted to send
    them. You are quie a fond of fatuous nonsense as Cursitor Doom.

    Not all that different, and you can test a new idea in LTSpice a lot
    faster than you can cobble stuff together on the bench.

    I stopped using it long ago (years).
    My stuff works.

    Because you don't try anything new?

    Very little is 'new'.
    My neural net has been trained on electronics since the early fifties of last century.

    Mine too. LTSpice isn't any kind of neural net.

    ELTheaSPice is just a word...

    It's quite a few words of computer program.

    Used it once to check some filter curves, but there are better filter programs.

    Of course there are - LTSpice is a simulation program, not a filter
    design program.

    It gave the wrong results on a simple amplifier I tried on it.

    So you didn't use it correctly.

    It is extremely limited and again compare it to the tennis player that trained a lifetime
    a joke basically.

    Far from it.

    Get into the very high frequency domain, did a lot of that stuff, it is then more about layout and wavelength and similar stuff
    how circuits behave.

    Been there, done that. LSpice isn't designed for that kind of work,
    though it does offer lossy delay line models. At high frequencies layout
    is all about stray capacitances, which you can model in LTSpice, but it
    gets very messy for anything complicated enough to be useful.

    ElTeaSprites is a bit like Hollowwood movies.

    Hollywood movies are expensive. LTSpice is free.

    Burb .. I mean Kirk.. well
    I do not question your genius,

    Sci.electronics.design does seem to be a genius-free space.

    It is design, if it works what is cooked up here, great!
    Sure got some interesting ideas from here that I tried.

    Design is a bit more than "cooking up stuff". It helps if you understand
    what you are doing and what you are trying to do.

    There are
    quite a few competent people who post here, but genius is rare, and most
    of the people who are called geniuses have exploited a stroke of luck
    that let them look better than they deserve, though as Pasteur said,
    chance does favour the prepared mind.

    My interests are much wider than electronics
    worked in many fields
    from electronics to TV to power stations to medical to aircraft to satellite ..what not.

    Who hasn't?

    Plowing through a lot of circuit variations quickly with LTSpice does
    give you more chances to win that particular lottery.

    Sounds like gambling...

    It might, to you.

    these days AI is using that method to try a zillion variation in medicine related creations.

    It's called the Monte Carlo approach. There are more systematic approaches.

    It may or may not work.
    But _understanding_comes first and is always the winner.
    Lucky shot may help too.

    There is nothing you can not do if you are sufficiently motivated.

    Twaddle. Excessively motivated people thrash around getting nowhere.

    As you say, understanding is the key, but LTSpice - in the right hands -
    can help you understand what's going on on the bench quite a lot faster
    than bench work on it's own.

    --
    Bill Sloman, Sydney

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Liz Tuddenham@21:1/5 to Bill Sloman on Wed Nov 6 14:50:47 2024
    Bill Sloman <bill.sloman@ieee.org> wrote:

    [...]
    LTSpice - in the right hands -
    can help you understand what's going on on the bench quite a lot faster
    than bench work on it's own.

    It can help you understand what *should* be going on but benchwork shows
    you what is really going on and it is up to you to understand why.
    learning by benchwork is slower because it is complicated by having to
    deal with reality.


    --
    ~ Liz Tuddenham ~
    (Remove the ".invalid"s and add ".co.uk" to reply)
    www.poppyrecords.co.uk

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Edward Rawde@21:1/5 to Jeroen Belleman on Wed Nov 6 11:05:02 2024
    "Jeroen Belleman" <jeroen@nospam.please> wrote in message news:vgfb8d$21qub$1@dont-email.me...
    On 11/6/24 03:39, Edward Rawde wrote:
    [Snip!]
    Now approacing 90dB if you believe the simulation with with this experimental circuit.
    You'll want to find something else to do while it simulates.
    How to inprove it further?

    Version 4
    [Deleted....]

    You are chasing ghosts. Simulation doesn't prove anything at this
    level. Build it and measure it.

    Jeroen Belleman


    I don't have the facilities to build and test it so I'll probably have to leave it there.
    I totally agree that simulation is no longer worthwhile on this circuit.
    The simulation time just gets longer and doesn't prove anything.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Bill Sloman@21:1/5 to Liz Tuddenham on Thu Nov 7 02:29:16 2024
    On 7/11/2024 1:50 am, Liz Tuddenham wrote:
    Bill Sloman <bill.sloman@ieee.org> wrote:

    [...]
    LTSpice - in the right hands -
    can help you understand what's going on on the bench quite a lot faster
    than bench work on it's own.

    It can help you understand what *should* be going on but bench work shows
    you what is really going on and it is up to you to understand why.

    But quite a lot of what you need to understand in bench work is captured
    by a decent simulation, and a whole lot faster than you can capture it
    on the bench.

    learning by benchwork is slower because it is complicated by having to
    deal with reality.

    Simulations capture quite a lot of what is going on on the bench.

    Sometimes the reality you have to deal with is easier to dig out of a
    well-set up simulation because you can fiddle with stuff in the
    simulation that you can't twiddle on the bench.

    A great deal of electronic design is getting the right concepts
    together, and while bench work is usually a safer way of doing that, it
    can also be quite a lot slower.

    The subjectivist audio people get quite sentimental about what their
    golden ears tell them. Peter Baxandall was an objectivist.

    --
    Bill Sloman, Sydney

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Jeroen Belleman@21:1/5 to john larkin on Wed Nov 6 17:40:08 2024
    On 11/6/24 17:26, john larkin wrote:
    On Wed, 6 Nov 2024 10:04:42 +0100, Jeroen Belleman
    <jeroen@nospam.please> wrote:

    On 11/6/24 03:39, Edward Rawde wrote:
    [Snip!]
    Now approacing 90dB if you believe the simulation with with this experimental circuit.
    You'll want to find something else to do while it simulates.
    How to inprove it further?

    Version 4
    [Deleted....]

    You are chasing ghosts. Simulation doesn't prove anything at this
    level. Build it and measure it.

    Jeroen Belleman

    Simulation won't asolutely prove what circuits would produce low THD,
    but it will pretty definitely show which circuits won't.

    Of course, a sim like this needs good opamp models.

    If one builds it and measures it, what would you use to measure the distortion?


    I'm old school: A passive notch filter. It's likely to be fiddly.

    Jeroen Belleman

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From john larkin@21:1/5 to jeroen@nospam.please on Wed Nov 6 08:26:35 2024
    On Wed, 6 Nov 2024 10:04:42 +0100, Jeroen Belleman
    <jeroen@nospam.please> wrote:

    On 11/6/24 03:39, Edward Rawde wrote:
    [Snip!]
    Now approacing 90dB if you believe the simulation with with this experimental circuit.
    You'll want to find something else to do while it simulates.
    How to inprove it further?

    Version 4
    [Deleted....]

    You are chasing ghosts. Simulation doesn't prove anything at this
    level. Build it and measure it.

    Jeroen Belleman

    Simulation won't asolutely prove what circuits would produce low THD,
    but it will pretty definitely show which circuits won't.

    Of course, a sim like this needs good opamp models.

    If one builds it and measures it, what would you use to measure the
    distortion?

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From john larkin@21:1/5 to Liz Tuddenham on Wed Nov 6 08:37:11 2024
    On Wed, 6 Nov 2024 14:50:47 +0000, liz@poppyrecords.invalid.invalid
    (Liz Tuddenham) wrote:

    Bill Sloman <bill.sloman@ieee.org> wrote:

    [...]
    LTSpice - in the right hands -
    can help you understand what's going on on the bench quite a lot faster
    than bench work on it's own.

    It can help you understand what *should* be going on but benchwork shows
    you what is really going on and it is up to you to understand why.
    learning by benchwork is slower because it is complicated by having to
    deal with reality.

    I'm now simulating a rugged transimpedance amp for capacitive oil
    level measurement. That would be a mess to evaluate by breadboarding,
    partly because the real thing needs ADCs and FPGAs and such, and it's
    hard to breadboard those.

    Once the sim is tuned, we'll go directly to product PCB layout without breadboarding.

    One nice thing about design by simulation is that we can do a
    schematic and PCB layout and set up to build some rev A first
    articles, and parallel all those time delays with code development, so
    we can start testing as soon as the first units are built.

    So the best breadboard is the first production unit.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From john larkin@21:1/5 to jeroen@nospam.please on Wed Nov 6 08:42:21 2024
    On Wed, 6 Nov 2024 17:40:08 +0100, Jeroen Belleman
    <jeroen@nospam.please> wrote:

    On 11/6/24 17:26, john larkin wrote:
    On Wed, 6 Nov 2024 10:04:42 +0100, Jeroen Belleman
    <jeroen@nospam.please> wrote:

    On 11/6/24 03:39, Edward Rawde wrote:
    [Snip!]
    Now approacing 90dB if you believe the simulation with with this experimental circuit.
    You'll want to find something else to do while it simulates.
    How to inprove it further?

    Version 4
    [Deleted....]

    You are chasing ghosts. Simulation doesn't prove anything at this
    level. Build it and measure it.

    Jeroen Belleman

    Simulation won't asolutely prove what circuits would produce low THD,
    but it will pretty definitely show which circuits won't.

    Of course, a sim like this needs good opamp models.

    If one builds it and measures it, what would you use to measure the
    distortion?


    I'm old school: A passive notch filter. It's likely to be fiddly.

    Jeroen Belleman

    LC? Just make sure that the inductors and capacitors are all linear.

    Even twin tee can generate distortion.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Liz Tuddenham@21:1/5 to Bill Sloman on Wed Nov 6 16:43:08 2024
    Bill Sloman <bill.sloman@ieee.org> wrote:

    On 7/11/2024 1:50 am, Liz Tuddenham wrote:
    Bill Sloman <bill.sloman@ieee.org> wrote:

    [...]
    LTSpice - in the right hands -
    can help you understand what's going on on the bench quite a lot faster
    than bench work on it's own.

    It can help you understand what *should* be going on but bench work shows you what is really going on and it is up to you to understand why.

    But quite a lot of what you need to understand in bench work is captured
    by a decent simulation, and a whole lot faster than you can capture it
    on the bench.

    learning by benchwork is slower because it is complicated by having to
    deal with reality.

    Simulations capture quite a lot of what is going on on the bench.

    Sometimes the reality you have to deal with is easier to dig out of a well-set up simulation because you can fiddle with stuff in the
    simulation that you can't twiddle on the bench.

    A great deal of electronic design is getting the right concepts
    together, and while bench work is usually a safer way of doing that, it
    can also be quite a lot slower.

    Yes, that was the point I was trying to make, it is slower but safer and
    more comprehensive.


    The subjectivist audio people get quite sentimental about what their
    golden ears tell them. Peter Baxandall was an objectivist.

    Most of the fundamental progress in quality audio has been done by objectivists. Subjectivists enjoy playing about with it, but they
    rarely discover more than a small part of the truth and usually
    misunderstand the fundamentals of the process.

    When PGAH Voigt invented the moving coil cutterhead (which was later
    'stolen' by Arthur Haddy to become the Decca FFRR system and then
    'stolen' again by Arnold Sugden to become the Connoisseur cutterhead),
    he didn't have a signal generator or an objective source of sound.
    Rather than rely on subjective effects, he equipped a piano with a
    weight which could be dropped on the keys to generate a consistent sound
    so that he could make objective measurements.

    The BBC did a great deal of objective research on loudspeakers because
    they found that different studios and microphones sounded better on
    different loudspeakers and they weren't content to just accept this as subjective audio folklore. That research gave us a step improvement in
    the quality of loudspeaker drive units.

    I recently did a great deal of work to get the best bass response from a loudspeaker in a small cabinet. When I demonstrated it to a group of
    record enthusiasts, one of them complained that it was playing notes
    that weren't on the records. I eventually discovered that he had always listened to those records on a clockwork gramophone which, in spite of
    its huge exponential acoustic transformer,. lost the bottom couple of
    octaves.


    --
    ~ Liz Tuddenham ~
    (Remove the ".invalid"s and add ".co.uk" to reply)
    www.poppyrecords.co.uk

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Edward Rawde@21:1/5 to Jan Panteltje on Wed Nov 6 12:21:39 2024
    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vgf4jc$7vn5$1@solani.org...
    On a sunny day (Tue, 5 Nov 2024 11:00:42 -0500) it happened "Edward Rawde" <invalid@invalid.invalid> wrote in <vgdffb$ibt$1@nnrp.usenet.blueworldhosting.com>:

    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vgccvm$6jk3$1@solani.org...
    On a sunny day (Mon, 4 Nov 2024 11:31:01 -0500) it happened "Edward Rawde" >>> <invalid@invalid.invalid> wrote in
    <vgass6$28u2$1@nnrp.usenet.blueworldhosting.com>:

    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vg9pnu$ekhh$1@solani.org...
    On a sunny day (Sun, 3 Nov 2024 23:06:04 -0500) it happened "Edward Rawde"
    <invalid@invalid.invalid> wrote in
    <vg9h7b$277o$1@nnrp.usenet.blueworldhosting.com>:

    Simulation isn't fast but if you let it complete and do an FFT on the last 30 seconds, it's 80dB down at all unwanted
    harmonics.
    There do however seem to be unwanted sidebands close in either side of 1KHz
    Any suggestions for improvement?

    Publish a circuit diagram.
    Not that hard to make !

    If you mean ASCII art, no thanks in the case of this circuit.

    Easy to make a screen shot of your spice circuit and upload it one of those free image publication sites

    You do not seriously expect readers to start ancient peesees and use millisoft widows emulators to run tea spices
    https://panteltje.nl/panteltje/scope_tv/diagram.jpg
    https://panteltje.nl/pub/swr_bridge_hl_lt_spice.gif


    These appear to be LTSpice, so why can't you use it to view my circuits?

    As I pointed out, am reading Usenet on a Raspbeery Pi4 8GB
    Does everything here from spectrum analyzing to audio to video play
    Why boot up an acient peesee to start a millisoft widows emulator
    to look up some 80 deebee thingy that likely never has a practical use?

    Well, Bessel came up with his functions long before FM broadcasting. Ok you can use Carson's rule but Wikipedia says:
    "In 1922 he published a mathematical treatment of frequency modulation (FM), which introduced the Carson bandwidth rule."
    Which pre dates FM broadcasting.

    While designing my circuit I found this document very useful: https://www.google.com/search?q=The+Field+Effect+Transistor+as+a+Voltage+Controlled+Resistor
    It doesn't mention doing anything in a lab.



    In any case if you can't simulate my circuits you won't be able to appreciate how brilliant a designer I am like Bill does.

    80 deebee makes me wonder if you not better spend your time on making e-bikes from vipes...
    com/gadgets/2024/11/disposable-vapes-from-a-music-festival-can-power-a-beefy-e-bike-20-miles/

    And elteasprites simu is not worth a thing, reality is different from the models used

    Reality is always different from models because models can never have everything that reality has.
    But this does not mean that models aren't useful.
    Simulation can do a lot to tell you you're going in the right direction.
    This can save a lot of time when you get to do it in reality.

    I stopped using it long ago (years)
    My stuff works.

    My sync separators worked too, back when I needed one.
    They weren't quite like yours, I think I got an idea from Video Handbook by someone, I forget who.


    ElTeaSprites is a bit like Hollowwood movies.
    Burb .. I mean Kirk.. well
    I do not question your genius,

    Well you should.
    Anyone who claims to be a genius might as well be telling you that they aren't.

    Just one more thing.
    Writing PC as peesee is fine if you're composing something like this: https://www.google.com/search?q=I+halve+a+spelling+chequer
    But doing it repeatedly with every other word starts to make your perceived age go down.




    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From john larkin@21:1/5 to invalid@invalid.invalid on Wed Nov 6 11:21:13 2024
    On Wed, 6 Nov 2024 12:21:39 -0500, "Edward Rawde"
    <invalid@invalid.invalid> wrote:

    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vgf4jc$7vn5$1@solani.org...
    On a sunny day (Tue, 5 Nov 2024 11:00:42 -0500) it happened "Edward Rawde" >> <invalid@invalid.invalid> wrote in
    <vgdffb$ibt$1@nnrp.usenet.blueworldhosting.com>:

    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vgccvm$6jk3$1@solani.org...
    On a sunny day (Mon, 4 Nov 2024 11:31:01 -0500) it happened "Edward Rawde" >>>> <invalid@invalid.invalid> wrote in
    <vgass6$28u2$1@nnrp.usenet.blueworldhosting.com>:

    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vg9pnu$ekhh$1@solani.org...
    On a sunny day (Sun, 3 Nov 2024 23:06:04 -0500) it happened "Edward Rawde"
    <invalid@invalid.invalid> wrote in
    <vg9h7b$277o$1@nnrp.usenet.blueworldhosting.com>:

    Simulation isn't fast but if you let it complete and do an FFT on the last 30 seconds, it's 80dB down at all unwanted
    harmonics.
    There do however seem to be unwanted sidebands close in either side of 1KHz
    Any suggestions for improvement?

    Publish a circuit diagram.
    Not that hard to make !

    If you mean ASCII art, no thanks in the case of this circuit.

    Easy to make a screen shot of your spice circuit and upload it one of those free image publication sites

    You do not seriously expect readers to start ancient peesees and use millisoft widows emulators to run tea spices
    https://panteltje.nl/panteltje/scope_tv/diagram.jpg
    https://panteltje.nl/pub/swr_bridge_hl_lt_spice.gif


    These appear to be LTSpice, so why can't you use it to view my circuits?

    As I pointed out, am reading Usenet on a Raspbeery Pi4 8GB
    Does everything here from spectrum analyzing to audio to video play
    Why boot up an acient peesee to start a millisoft widows emulator
    to look up some 80 deebee thingy that likely never has a practical use?

    Well, Bessel came up with his functions long before FM broadcasting. Ok you can use Carson's rule but Wikipedia says:
    "In 1922 he published a mathematical treatment of frequency modulation (FM), which introduced the Carson bandwidth rule."
    Which pre dates FM broadcasting.

    While designing my circuit I found this document very useful: >https://www.google.com/search?q=The+Field+Effect+Transistor+as+a+Voltage+Controlled+Resistor
    It doesn't mention doing anything in a lab.



    In any case if you can't simulate my circuits you won't be able to appreciate how brilliant a designer I am like Bill does.

    80 deebee makes me wonder if you not better spend your time on making e-bikes from vipes...
    com/gadgets/2024/11/disposable-vapes-from-a-music-festival-can-power-a-beefy-e-bike-20-miles/

    And elteasprites simu is not worth a thing, reality is different from the models used

    Reality is always different from models because models can never have everything that reality has.
    But this does not mean that models aren't useful.
    Simulation can do a lot to tell you you're going in the right direction.
    This can save a lot of time when you get to do it in reality.

    I stopped using it long ago (years)
    My stuff works.

    My sync separators worked too, back when I needed one.
    They weren't quite like yours, I think I got an idea from Video Handbook by someone, I forget who.


    ElTeaSprites is a bit like Hollowwood movies.
    Burb .. I mean Kirk.. well
    I do not question your genius,

    Well you should.
    Anyone who claims to be a genius might as well be telling you that they aren't.

    Just one more thing.
    Writing PC as peesee is fine if you're composing something like this: >https://www.google.com/search?q=I+halve+a+spelling+chequer
    But doing it repeatedly with every other word starts to make your perceived age go down.





    It's interesting that the classic filters (Butterworth, Chebychev,
    Cauer) are based on mathematical approximations that pre-date
    electronics. They were used to compose tables for artillery or
    something.

    But filters don't have to implement that math. One can Spice a filter
    and tweak it (say, to use available parts) to do whetever works for
    you.

    An LC or active filter from the Williams or Lancaster books can be a
    starting point.

    We discussed non-reflective LC filters here some years ago, and they
    were mostly hacked by simulation. The new Mini-Circuits absorptive
    filters have more theory behind them.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Liz Tuddenham@21:1/5 to john larkin on Wed Nov 6 22:15:38 2024
    john larkin <jl@glen--canyon.com> wrote:

    [...]
    It's interesting that the classic filters (Butterworth, Chebychev,
    Cauer) are based on mathematical approximations that pre-date
    electronics. They were used to compose tables for artillery or
    something.

    Chebychef did his calculations on the mechancal lnkages used to operate
    the valves of steam locomotives, generating linear motion and sharp
    movement from the superimposed effects of rotary motions.


    --
    ~ Liz Tuddenham ~
    (Remove the ".invalid"s and add ".co.uk" to reply)
    www.poppyrecords.co.uk

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Jeroen Belleman@21:1/5 to Liz Tuddenham on Wed Nov 6 23:23:16 2024
    On 11/6/24 23:15, Liz Tuddenham wrote:
    john larkin <jl@glen--canyon.com> wrote:

    [...]
    It's interesting that the classic filters (Butterworth, Chebychev,
    Cauer) are based on mathematical approximations that pre-date
    electronics. They were used to compose tables for artillery or
    something.

    Chebychef did his calculations on the mechancal lnkages used to operate
    the valves of steam locomotives, generating linear motion and sharp
    movement from the superimposed effects of rotary motions.

    Did he indeed? Interesting. Do you perchance have a reference?

    Thanks,
    Jeroen Belleman

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Jeroen Belleman@21:1/5 to john larkin on Wed Nov 6 23:20:07 2024
    On 11/6/24 17:42, john larkin wrote:
    On Wed, 6 Nov 2024 17:40:08 +0100, Jeroen Belleman
    <jeroen@nospam.please> wrote:

    On 11/6/24 17:26, john larkin wrote:
    On Wed, 6 Nov 2024 10:04:42 +0100, Jeroen Belleman
    <jeroen@nospam.please> wrote:

    On 11/6/24 03:39, Edward Rawde wrote:
    [Snip!]
    Now approacing 90dB if you believe the simulation with with this experimental circuit.
    You'll want to find something else to do while it simulates.
    How to inprove it further?

    Version 4
    [Deleted....]

    You are chasing ghosts. Simulation doesn't prove anything at this
    level. Build it and measure it.

    Jeroen Belleman

    Simulation won't asolutely prove what circuits would produce low THD,
    but it will pretty definitely show which circuits won't.

    Of course, a sim like this needs good opamp models.

    If one builds it and measures it, what would you use to measure the
    distortion?


    I'm old school: A passive notch filter. It's likely to be fiddly.

    Jeroen Belleman

    LC? Just make sure that the inductors and capacitors are all linear.

    Even twin tee can generate distortion.


    Twin tee is what I was thinking of, indeed. Of course, it's essential
    to use carefully matched components of good quality. It would be
    fiddly, yes.

    In some distant past, I've used a box we called a 'Null Detector'
    which did just that. You'd null out the fundamental, and what was
    left was the distortion. I don't recall if it was good enough for
    -80dB though.

    Jeroen Belleman

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From john larkin@21:1/5 to Liz Tuddenham on Wed Nov 6 15:20:21 2024
    On Wed, 6 Nov 2024 22:15:38 +0000, liz@poppyrecords.invalid.invalid
    (Liz Tuddenham) wrote:

    john larkin <jl@glen--canyon.com> wrote:

    [...]
    It's interesting that the classic filters (Butterworth, Chebychev,
    Cauer) are based on mathematical approximations that pre-date
    electronics. They were used to compose tables for artillery or
    something.

    Chebychef did his calculations on the mechancal lnkages used to operate
    the valves of steam locomotives, generating linear motion and sharp
    movement from the superimposed effects of rotary motions.

    I think the general idea is that if you truncate a power series, here
    is a better set of coefficients than just chopping off the infinite
    set.

    That mattered when math tables were computed by hand. Nowadays, a
    computer can just use the first 150 terms.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From john larkin@21:1/5 to jeroen@nospam.please on Wed Nov 6 15:24:47 2024
    On Wed, 6 Nov 2024 23:20:07 +0100, Jeroen Belleman
    <jeroen@nospam.please> wrote:

    On 11/6/24 17:42, john larkin wrote:
    On Wed, 6 Nov 2024 17:40:08 +0100, Jeroen Belleman
    <jeroen@nospam.please> wrote:

    On 11/6/24 17:26, john larkin wrote:
    On Wed, 6 Nov 2024 10:04:42 +0100, Jeroen Belleman
    <jeroen@nospam.please> wrote:

    On 11/6/24 03:39, Edward Rawde wrote:
    [Snip!]
    Now approacing 90dB if you believe the simulation with with this experimental circuit.
    You'll want to find something else to do while it simulates.
    How to inprove it further?

    Version 4
    [Deleted....]

    You are chasing ghosts. Simulation doesn't prove anything at this
    level. Build it and measure it.

    Jeroen Belleman

    Simulation won't asolutely prove what circuits would produce low THD,
    but it will pretty definitely show which circuits won't.

    Of course, a sim like this needs good opamp models.

    If one builds it and measures it, what would you use to measure the
    distortion?


    I'm old school: A passive notch filter. It's likely to be fiddly.

    Jeroen Belleman

    LC? Just make sure that the inductors and capacitors are all linear.

    Even twin tee can generate distortion.


    Twin tee is what I was thinking of, indeed. Of course, it's essential
    to use carefully matched components of good quality. It would be
    fiddly, yes.

    One could use a good resistive divider to halve the signal amplitude.
    If the filter is linear, the THD shouldn't change.

    Or add a bit of DC bias.

    Ceramic caps can be awful.


    In some distant past, I've used a box we called a 'Null Detector'
    which did just that. You'd null out the fundamental, and what was
    left was the distortion. I don't recall if it was good enough for
    -80dB though.

    Jeroen Belleman




    "Selective Voltmeters" were cool. I think I still have an old HP.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Bill Sloman@21:1/5 to john larkin on Thu Nov 7 16:23:52 2024
    On 7/11/2024 10:20 am, john larkin wrote:
    On Wed, 6 Nov 2024 22:15:38 +0000, liz@poppyrecords.invalid.invalid
    (Liz Tuddenham) wrote:

    john larkin <jl@glen--canyon.com> wrote:

    [...]
    It's interesting that the classic filters (Butterworth, Chebychev,
    Cauer) are based on mathematical approximations that pre-date
    electronics. They were used to compose tables for artillery or
    something.

    Chebychef did his calculations on the mechancal lnkages used to operate
    the valves of steam locomotives, generating linear motion and sharp
    movement from the superimposed effects of rotary motions.

    I think the general idea is that if you truncate a power series, here
    is a better set of coefficients than just chopping off the infinite
    set.

    That mattered when math tables were computed by hand. Nowadays, a
    computer can just use the first 150 terms.

    That's a Russian (brute force) solution. Hamming windows are
    computationally cheaper.

    --
    Bill Sloman, Sydney

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Jan Panteltje@21:1/5 to invalid@invalid.invalid on Thu Nov 7 05:57:24 2024
    On a sunny day (Wed, 6 Nov 2024 12:21:39 -0500) it happened "Edward Rawde" <invalid@invalid.invalid> wrote in <vgg8j4$k3i$1@nnrp.usenet.blueworldhosting.com>:

    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vgf4jc$7vn5$1@solani.org...
    On a sunny day (Tue, 5 Nov 2024 11:00:42 -0500) it happened "Edward Rawde" >> <invalid@invalid.invalid> wrote in
    <vgdffb$ibt$1@nnrp.usenet.blueworldhosting.com>:

    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vgccvm$6jk3$1@solani.org...
    On a sunny day (Mon, 4 Nov 2024 11:31:01 -0500) it happened "Edward Rawde" >>>> <invalid@invalid.invalid> wrote in
    <vgass6$28u2$1@nnrp.usenet.blueworldhosting.com>:

    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vg9pnu$ekhh$1@solani.org...
    On a sunny day (Sun, 3 Nov 2024 23:06:04 -0500) it happened "Edward Rawde"
    <invalid@invalid.invalid> wrote in
    <vg9h7b$277o$1@nnrp.usenet.blueworldhosting.com>:

    Simulation isn't fast but if you let it complete and do an FFT on the last 30 seconds, it's 80dB down at all unwanted
    harmonics.
    There do however seem to be unwanted sidebands close in either side of 1KHz
    Any suggestions for improvement?

    Publish a circuit diagram.
    Not that hard to make !

    If you mean ASCII art, no thanks in the case of this circuit.

    Easy to make a screen shot of your spice circuit and upload it one of those free image publication sites

    You do not seriously expect readers to start ancient peesees and use millisoft widows emulators to run tea spices
    https://panteltje.nl/panteltje/scope_tv/diagram.jpg
    https://panteltje.nl/pub/swr_bridge_hl_lt_spice.gif


    These appear to be LTSpice, so why can't you use it to view my circuits?

    As I pointed out, am reading Usenet on a Raspbeery Pi4 8GB
    Does everything here from spectrum analyzing to audio to video play
    Why boot up an acient peesee to start a millisoft widows emulator
    to look up some 80 deebee thingy that likely never has a practical use?

    Well, Bessel came up with his functions long before FM broadcasting. Ok you can use Carson's rule but Wikipedia says:
    "In 1922 he published a mathematical treatment of frequency modulation (FM), which introduced the Carson bandwidth rule."
    Which pre dates FM broadcasting.

    While designing my circuit I found this document very useful: >https://www.google.com/search?q=The+Field+Effect+Transistor+as+a+Voltage+Controlled+Resistor
    It doesn't mention doing anything in a lab.



    In any case if you can't simulate my circuits you won't be able to appreciate how brilliant a designer I am like Bill does.

    80 deebee makes me wonder if you not better spend your time on making e-bikes from vipes...
    com/gadgets/2024/11/disposable-vapes-from-a-music-festival-can-power-a-beefy-e-bike-20-miles/

    And elteasprites simu is not worth a thing, reality is different from the models used

    Reality is always different from models because models can never have everything that reality has.
    But this does not mean that models aren't useful.
    Simulation can do a lot to tell you you're going in the right direction.
    This can save a lot of time when you get to do it in reality.

    I stopped using it long ago (years)
    My stuff works.

    My sync separators worked too, back when I needed one.
    They weren't quite like yours, I think I got an idea from Video Handbook by someone, I forget who.


    ElTeaSprites is a bit like Hollowwood movies.
    Burb .. I mean Kirk.. well
    I do not question your genius,

    Well you should.
    Anyone who claims to be a genius might as well be telling you that they aren't.

    Just one more thing.
    Writing PC as peesee is fine if you're composing something like this: >https://www.google.com/search?q=I+halve+a+spelling+chequer
    But doing it repeatedly with every other word starts to make your perceived age go down.

    I use my spell shaker

    For other 'tronics, when going back in time, sixties seventies when working in the teefee studios
    I had to keep a zillion pieces of interconnected equipment running often with a very short time to fix things or work around the problem,
    as 'the show must go on', and as it was the national network no black screen or 'sorry' allowed.
    Having a studio full of contracted artists waiting for an hour is a no no too. From film to videotape to all sort of cameras, synchronization, Eurovision network, management, fault finding
    what not
    Having had to repair (and to do that get into depth of all that stuff) often within minutes makes you aware of so many different designs by
    so many different companies that it widens the spectrum of your neural net... Later I also had my own teefee repair shop... Then after that went to design stuff for all sort of things
    Bit different from being stuck in one thing, also you learn what counts
    But you need to know the basics, not only of the components, but also of the systems, the organization,
    who has the power,,, What to do in emergencies with hundreds of people on the set.. Public too sometimes.
    And we had the famous red phone from the government that would / could ring and special procedures were to be followed
    some stored in a safe, national emergency, unite the several channels, did head control room for a while too, not just 'tronics.
    Fun, some could not handle it, seen them go,

    to pea in the sea .. it may help some here who only can commie-nukate in one language to at least do some self-inspection
    or flex their brain's language center a bit .

    Yea geny -us ?
    https://www.bol.com/nl/nl/p/geny-geest-van-aladdin-vintage-speelfiguurtje-disney-8cm/9300000066971215/

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Jan Panteltje@21:1/5 to Liz Tuddenham on Thu Nov 7 06:12:55 2024
    On a sunny day (Wed, 6 Nov 2024 16:43:08 +0000) it happened liz@poppyrecords.invalid.invalid (Liz Tuddenham) wrote in <1r2m054.1q0xoeb13sbyfqN%liz@poppyrecords.invalid.invalid>:

    Bill Sloman <bill.sloman@ieee.org> wrote:

    On 7/11/2024 1:50 am, Liz Tuddenham wrote:
    Bill Sloman <bill.sloman@ieee.org> wrote:

    [...]
    LTSpice - in the right hands -
    can help you understand what's going on on the bench quite a lot faster >> >> than bench work on it's own.

    It can help you understand what *should* be going on but bench work shows >> > you what is really going on and it is up to you to understand why.

    But quite a lot of what you need to understand in bench work is captured
    by a decent simulation, and a whole lot faster than you can capture it
    on the bench.

    learning by benchwork is slower because it is complicated by having to
    deal with reality.

    Simulations capture quite a lot of what is going on on the bench.

    Sometimes the reality you have to deal with is easier to dig out of a
    well-set up simulation because you can fiddle with stuff in the
    simulation that you can't twiddle on the bench.

    A great deal of electronic design is getting the right concepts
    together, and while bench work is usually a safer way of doing that, it
    can also be quite a lot slower.

    Yes, that was the point I was trying to make, it is slower but safer and
    more comprehensive.


    The subjectivist audio people get quite sentimental about what their
    golden ears tell them. Peter Baxandall was an objectivist.

    Most of the fundamental progress in quality audio has been done by >objectivists. Subjectivists enjoy playing about with it, but they
    rarely discover more than a small part of the truth and usually
    misunderstand the fundamentals of the process.

    When PGAH Voigt invented the moving coil cutterhead (which was later
    'stolen' by Arthur Haddy to become the Decca FFRR system and then
    'stolen' again by Arnold Sugden to become the Connoisseur cutterhead),
    he didn't have a signal generator or an objective source of sound.
    Rather than rely on subjective effects, he equipped a piano with a
    weight which could be dropped on the keys to generate a consistent sound
    so that he could make objective measurements.

    The BBC did a great deal of objective research on loudspeakers because
    they found that different studios and microphones sounded better on
    different loudspeakers and they weren't content to just accept this as >subjective audio folklore. That research gave us a step improvement in
    the quality of loudspeaker drive units.

    I recently did a great deal of work to get the best bass response from a >loudspeaker in a small cabinet. When I demonstrated it to a group of
    record enthusiasts, one of them complained that it was playing notes
    that weren't on the records. I eventually discovered that he had always >listened to those records on a clockwork gramophone which, in spite of
    its huge exponential acoustic transformer,. lost the bottom couple of >octaves.

    Speakers and room acoustics...
    I have some, everything is different, should be.
    I liked the Quad electrostats, just have some chaep bass-reflex boxes now.
    Much on bluetouth headphones these days listening to teefee.
    Also when I practice playing on my keyboard, big Sennheiser HD201 headphones, can make mistakes without upsetting Annie Whan.
    Else Annie starts singing along at times.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Edward Rawde@21:1/5 to Jan Panteltje on Thu Nov 7 02:23:23 2024
    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vghks5$9ces$1@solani.org...
    On a sunny day (Wed, 6 Nov 2024 12:21:39 -0500) it happened "Edward Rawde" <invalid@invalid.invalid> wrote in <vgg8j4$k3i$1@nnrp.usenet.blueworldhosting.com>:

    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vgf4jc$7vn5$1@solani.org...
    On a sunny day (Tue, 5 Nov 2024 11:00:42 -0500) it happened "Edward Rawde" >>> <invalid@invalid.invalid> wrote in
    <vgdffb$ibt$1@nnrp.usenet.blueworldhosting.com>:

    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vgccvm$6jk3$1@solani.org...
    On a sunny day (Mon, 4 Nov 2024 11:31:01 -0500) it happened "Edward Rawde"
    <invalid@invalid.invalid> wrote in
    <vgass6$28u2$1@nnrp.usenet.blueworldhosting.com>:

    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vg9pnu$ekhh$1@solani.org...
    On a sunny day (Sun, 3 Nov 2024 23:06:04 -0500) it happened "Edward Rawde"
    <invalid@invalid.invalid> wrote in
    <vg9h7b$277o$1@nnrp.usenet.blueworldhosting.com>:

    Simulation isn't fast but if you let it complete and do an FFT on the last 30 seconds, it's 80dB down at all unwanted
    harmonics.
    There do however seem to be unwanted sidebands close in either side of 1KHz
    Any suggestions for improvement?

    Publish a circuit diagram.
    Not that hard to make !


    Did someone ruffle your feathers?

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Liz Tuddenham@21:1/5 to Jan Panteltje on Thu Nov 7 08:40:02 2024
    Jan Panteltje <alien@comet.invalid> wrote:

    [...]
    Speakers and room acoustics...
    I have some, everything is different, should be.
    I liked the Quad electrostats,

    You needed a lot of space and good room acoustics to get the best out of
    them.

    just have some chaep bass-reflex boxes now.

    Bass-reflex looks good on paper but sounds horrible. The human ear
    hears the 6dB/octave roll off as 'natural' but with an unnatural 'honk' superimpose on it. Bass transients are coloured by the honk and give
    hang-over effects.

    It may not matter for synthetic pop music, but bass-reflex speakers can
    give misleading results if they are used for monitoring acoustic music recordings.

    --
    ~ Liz Tuddenham ~
    (Remove the ".invalid"s and add ".co.uk" to reply)
    www.poppyrecords.co.uk

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Liz Tuddenham@21:1/5 to Jeroen Belleman on Thu Nov 7 08:40:01 2024
    Jeroen Belleman <jeroen@nospam.please> wrote:

    On 11/6/24 23:15, Liz Tuddenham wrote:
    john larkin <jl@glen--canyon.com> wrote:

    [...]
    It's interesting that the classic filters (Butterworth, Chebychev,
    Cauer) are based on mathematical approximations that pre-date
    electronics. They were used to compose tables for artillery or
    something.

    Chebychef did his calculations on the mechancal lnkages used to operate
    the valves of steam locomotives, generating linear motion and sharp movement from the superimposed effects of rotary motions.

    Did he indeed? Interesting. Do you perchance have a reference?

    I remembered reading about his work on steam engines several decades
    ago, but can't give you a reference. Apparently the maths he developed
    for sharp steam valve movement was later found to be applicable to
    electronic filter cutoffs as well. The linkages for linear motion were something I didn't know about until I looked it up on Wikipedia.


    --
    ~ Liz Tuddenham ~
    (Remove the ".invalid"s and add ".co.uk" to reply)
    www.poppyrecords.co.uk

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Jan Panteltje@21:1/5 to Liz Tuddenham on Thu Nov 7 11:05:37 2024
    On a sunny day (Thu, 7 Nov 2024 08:40:02 +0000) it happened liz@poppyrecords.invalid.invalid (Liz Tuddenham) wrote in <1r2n91y.4mv6llmpj328N%liz@poppyrecords.invalid.invalid>:

    Jan Panteltje <alien@comet.invalid> wrote:

    [...]
    Speakers and room acoustics...
    I have some, everything is different, should be.
    I liked the Quad electrostats,

    You needed a lot of space and good room acoustics to get the best out of >them.

    just have some chaep bass-reflex boxes now.

    Bass-reflex looks good on paper but sounds horrible. The human ear
    hears the 6dB/octave roll off as 'natural' but with an unnatural 'honk' >superimpose on it. Bass transients are coloured by the honk and give >hang-over effects.

    It may not matter for synthetic pop music, but bass-reflex speakers can
    give misleading results if they are used for monitoring acoustic music >recordings.

    Yes, OTOH the sound is a lot better than what came out of the TV speakers :-) The boxes have some piezos for high frequency too:
    https://images.marktplaats.com/api/v1/listing-mp-p/images/34/34ab31bf-bc98-44d0-a210-b8ea75e074dd?rule=ecg_mp_eps$_83
    now > 20 years old..

    Was cheap,
    also have a Mc Crypt power amp to drive it:
    https://asset.conrad.com/media10/add/160267/c1/-/gl/000302573ML02/manual-302573-mc-crypt-xpa-225.pdf
    2 x 100W sine into 8 Ohm
    Used it for all sort of things,

    And this one of course:
    https://panteltje.nl/panteltje/amplifier/index.html
    nice chip, been on about 12 hours a day since year 2000?

    So, as you can see, I am no audiophile...
    That last amp also drives my cryo-cooler with 60 Hz in mechanocal resonance via a reverse connected main transformer for 50 Hz (for a.o. anti-graffity experiments>_
    https://panteltje.nl/pub/cryo/

    or maybe if you need cooling for an ultra-low-noise amp?
    or just to make some rocket fuel..

    I just found this:
    https://panteltje.nl/pub/audio_90_degrees_phase_shifter_top_IMG_6903.JPG
    https://panteltje.nl/pub/audio_90_degrees_phase_shifter_bottom_IMG_6904.JPG
    https://panteltje.nl/pub/audio_90_degrees_phase_shifter_circuit_diagram_IMG_6958.JPG
    https://panteltje.nl/pub/audio_90_degrees_phase_shifter_PCB_top_view_IMG_6962.JPG
    https://panteltje.nl/pub/audio_90_degrees_phase_shifter_PCB_bottom_view_IMG_6960.JPG
    Thst is a 90 degrees phase shifter over the speech audio range for generating I and Q signals for SSB modulation.
    design is not mine, used trimpots to test it :-)
    One of many experiments...

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Jeroen Belleman@21:1/5 to Liz Tuddenham on Thu Nov 7 11:19:01 2024
    On 11/7/24 09:40, Liz Tuddenham wrote:
    Jeroen Belleman <jeroen@nospam.please> wrote:

    On 11/6/24 23:15, Liz Tuddenham wrote:
    john larkin <jl@glen--canyon.com> wrote:

    [...]
    It's interesting that the classic filters (Butterworth, Chebychev,
    Cauer) are based on mathematical approximations that pre-date
    electronics. They were used to compose tables for artillery or
    something.

    Chebychef did his calculations on the mechancal lnkages used to operate
    the valves of steam locomotives, generating linear motion and sharp
    movement from the superimposed effects of rotary motions.

    Did he indeed? Interesting. Do you perchance have a reference?

    I remembered reading about his work on steam engines several decades
    ago, but can't give you a reference. Apparently the maths he developed
    for sharp steam valve movement was later found to be applicable to
    electronic filter cutoffs as well. The linkages for linear motion were something I didn't know about until I looked it up on Wikipedia.



    Thanks. Mechanical linkages are interesting and fun and obviously
    useful. Have you heard of Theo Jansen's 'strandbeest'? Plastic pipe contraptions that 'walk' on the beach powered by wind. They are
    eerily life-like.

    Jeroen Belleman

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From albert@spenarnc.xs4all.nl@21:1/5 to jl@glen--canyon.com on Thu Nov 7 13:23:27 2024
    In article <n5unijlr25iffo7v22eb3rhg5pcnrk87nv@4ax.com>,
    john larkin <jl@glen--canyon.com> wrote:
    On Wed, 6 Nov 2024 22:15:38 +0000, liz@poppyrecords.invalid.invalid
    (Liz Tuddenham) wrote:

    john larkin <jl@glen--canyon.com> wrote:

    [...]
    It's interesting that the classic filters (Butterworth, Chebychev,
    Cauer) are based on mathematical approximations that pre-date
    electronics. They were used to compose tables for artillery or
    something.

    Chebychef did his calculations on the mechancal lnkages used to operate
    the valves of steam locomotives, generating linear motion and sharp >>movement from the superimposed effects of rotary motions.

    I think the general idea is that if you truncate a power series, here
    is a better set of coefficients than just chopping off the infinite
    set.

    That mattered when math tables were computed by hand. Nowadays, a
    computer can just use the first 150 terms.

    They can, but don't do that. Wasting computer time for using a
    lot of terms is just wasteful. Minimax polynomials and the likes
    (rational approximations) are used all over the place, thanks
    Tsjebisjof.


    Groetjes Albert
    --
    Temu exploits Christians: (Disclaimer, only 10 apostles)
    Last Supper Acrylic Suncatcher - 15Cm Round Stained Glass- Style Wall
    Art For Home, Office And Garden Decor - Perfect For Windows, Bars,
    And Gifts For Friends Family And Colleagues.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From john larkin@21:1/5 to albert@spenarnc.xs4all.nl on Thu Nov 7 07:21:53 2024
    On Thu, 07 Nov 2024 13:23:27 +0100, albert@spenarnc.xs4all.nl wrote:

    In article <n5unijlr25iffo7v22eb3rhg5pcnrk87nv@4ax.com>,
    john larkin <jl@glen--canyon.com> wrote:
    On Wed, 6 Nov 2024 22:15:38 +0000, liz@poppyrecords.invalid.invalid
    (Liz Tuddenham) wrote:

    john larkin <jl@glen--canyon.com> wrote:

    [...]
    It's interesting that the classic filters (Butterworth, Chebychev,
    Cauer) are based on mathematical approximations that pre-date
    electronics. They were used to compose tables for artillery or
    something.

    Chebychef did his calculations on the mechancal lnkages used to operate >>>the valves of steam locomotives, generating linear motion and sharp >>>movement from the superimposed effects of rotary motions.

    I think the general idea is that if you truncate a power series, here
    is a better set of coefficients than just chopping off the infinite
    set.

    That mattered when math tables were computed by hand. Nowadays, a
    computer can just use the first 150 terms.

    They can, but don't do that. Wasting computer time for using a
    lot of terms is just wasteful. Minimax polynomials and the likes
    (rational approximations) are used all over the place, thanks
    Tsjebisjof.


    Groetjes Albert

    Calculating a sine or a log to 15 significant digits wastes
    milliwatts. AI wastes gigawatts.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From john larkin@21:1/5 to All on Thu Nov 7 07:23:39 2024
    On Thu, 07 Nov 2024 05:57:24 GMT, Jan Panteltje <alien@comet.invalid>
    wrote:

    On a sunny day (Wed, 6 Nov 2024 12:21:39 -0500) it happened "Edward Rawde" ><invalid@invalid.invalid> wrote in ><vgg8j4$k3i$1@nnrp.usenet.blueworldhosting.com>:

    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vgf4jc$7vn5$1@solani.org...
    On a sunny day (Tue, 5 Nov 2024 11:00:42 -0500) it happened "Edward Rawde" >>> <invalid@invalid.invalid> wrote in
    <vgdffb$ibt$1@nnrp.usenet.blueworldhosting.com>:

    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vgccvm$6jk3$1@solani.org...
    On a sunny day (Mon, 4 Nov 2024 11:31:01 -0500) it happened "Edward Rawde"
    <invalid@invalid.invalid> wrote in
    <vgass6$28u2$1@nnrp.usenet.blueworldhosting.com>:

    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vg9pnu$ekhh$1@solani.org...
    On a sunny day (Sun, 3 Nov 2024 23:06:04 -0500) it happened "Edward Rawde"
    <invalid@invalid.invalid> wrote in
    <vg9h7b$277o$1@nnrp.usenet.blueworldhosting.com>:

    Simulation isn't fast but if you let it complete and do an FFT on the last 30 seconds, it's 80dB down at all unwanted
    harmonics.
    There do however seem to be unwanted sidebands close in either side of 1KHz
    Any suggestions for improvement?

    Publish a circuit diagram.
    Not that hard to make !

    If you mean ASCII art, no thanks in the case of this circuit.

    Easy to make a screen shot of your spice circuit and upload it one of those free image publication sites

    You do not seriously expect readers to start ancient peesees and use millisoft widows emulators to run tea spices
    https://panteltje.nl/panteltje/scope_tv/diagram.jpg
    https://panteltje.nl/pub/swr_bridge_hl_lt_spice.gif


    These appear to be LTSpice, so why can't you use it to view my circuits? >>>
    As I pointed out, am reading Usenet on a Raspbeery Pi4 8GB
    Does everything here from spectrum analyzing to audio to video play
    Why boot up an acient peesee to start a millisoft widows emulator
    to look up some 80 deebee thingy that likely never has a practical use?

    Well, Bessel came up with his functions long before FM broadcasting. Ok you can use Carson's rule but Wikipedia says:
    "In 1922 he published a mathematical treatment of frequency modulation (FM), which introduced the Carson bandwidth rule."
    Which pre dates FM broadcasting.

    While designing my circuit I found this document very useful: >>https://www.google.com/search?q=The+Field+Effect+Transistor+as+a+Voltage+Controlled+Resistor
    It doesn't mention doing anything in a lab.



    In any case if you can't simulate my circuits you won't be able to appreciate how brilliant a designer I am like Bill does.

    80 deebee makes me wonder if you not better spend your time on making e-bikes from vipes...
    com/gadgets/2024/11/disposable-vapes-from-a-music-festival-can-power-a-beefy-e-bike-20-miles/

    And elteasprites simu is not worth a thing, reality is different from the models used

    Reality is always different from models because models can never have everything that reality has.
    But this does not mean that models aren't useful.
    Simulation can do a lot to tell you you're going in the right direction. >>This can save a lot of time when you get to do it in reality.

    I stopped using it long ago (years)
    My stuff works.

    My sync separators worked too, back when I needed one.
    They weren't quite like yours, I think I got an idea from Video Handbook by someone, I forget who.


    ElTeaSprites is a bit like Hollowwood movies.
    Burb .. I mean Kirk.. well
    I do not question your genius,

    Well you should.
    Anyone who claims to be a genius might as well be telling you that they aren't.

    Just one more thing.
    Writing PC as peesee is fine if you're composing something like this: >>https://www.google.com/search?q=I+halve+a+spelling+chequer
    But doing it repeatedly with every other word starts to make your perceived age go down.

    I use my spell shaker

    Your posts are getting ever more annoying and unreadable.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Jan Panteltje@21:1/5 to JL@gct.com on Thu Nov 7 15:48:47 2024
    On a sunny day (Thu, 07 Nov 2024 07:23:39 -0800) it happened john larkin <JL@gct.com> wrote in <6pmpijtkajbkj56h714ldothonrflfdqra@4ax.com>:

    On Thu, 07 Nov 2024 05:57:24 GMT, Jan Panteltje <alien@comet.invalid>
    wrote:

    On a sunny day (Wed, 6 Nov 2024 12:21:39 -0500) it happened "Edward Rawde" >><invalid@invalid.invalid> wrote in >><vgg8j4$k3i$1@nnrp.usenet.blueworldhosting.com>:

    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vgf4jc$7vn5$1@solani.org...
    On a sunny day (Tue, 5 Nov 2024 11:00:42 -0500) it happened "Edward Rawde" >>>> <invalid@invalid.invalid> wrote in
    <vgdffb$ibt$1@nnrp.usenet.blueworldhosting.com>:

    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vgccvm$6jk3$1@solani.org...
    On a sunny day (Mon, 4 Nov 2024 11:31:01 -0500) it happened "Edward Rawde"
    <invalid@invalid.invalid> wrote in
    <vgass6$28u2$1@nnrp.usenet.blueworldhosting.com>:

    "Jan Panteltje" <alien@comet.invalid> wrote in message news:vg9pnu$ekhh$1@solani.org...
    On a sunny day (Sun, 3 Nov 2024 23:06:04 -0500) it happened "Edward Rawde"
    <invalid@invalid.invalid> wrote in
    <vg9h7b$277o$1@nnrp.usenet.blueworldhosting.com>:

    Simulation isn't fast but if you let it complete and do an FFT on the last 30 seconds, it's 80dB down at all unwanted
    harmonics.
    There do however seem to be unwanted sidebands close in either side of 1KHz
    Any suggestions for improvement?

    Publish a circuit diagram.
    Not that hard to make !

    If you mean ASCII art, no thanks in the case of this circuit.

    Easy to make a screen shot of your spice circuit and upload it one of those free image publication sites

    You do not seriously expect readers to start ancient peesees and use millisoft widows emulators to run tea spices
    https://panteltje.nl/panteltje/scope_tv/diagram.jpg
    https://panteltje.nl/pub/swr_bridge_hl_lt_spice.gif


    These appear to be LTSpice, so why can't you use it to view my circuits? >>>>
    As I pointed out, am reading Usenet on a Raspbeery Pi4 8GB
    Does everything here from spectrum analyzing to audio to video play
    Why boot up an acient peesee to start a millisoft widows emulator
    to look up some 80 deebee thingy that likely never has a practical use? >>>
    Well, Bessel came up with his functions long before FM broadcasting. Ok you can use Carson's rule but Wikipedia says:
    "In 1922 he published a mathematical treatment of frequency modulation (FM), which introduced the Carson bandwidth rule."
    Which pre dates FM broadcasting.

    While designing my circuit I found this document very useful: >>>https://www.google.com/search?q=The+Field+Effect+Transistor+as+a+Voltage+Controlled+Resistor
    It doesn't mention doing anything in a lab.



    In any case if you can't simulate my circuits you won't be able to appreciate how brilliant a designer I am like Bill does.

    80 deebee makes me wonder if you not better spend your time on making e-bikes from vipes...
    com/gadgets/2024/11/disposable-vapes-from-a-music-festival-can-power-a-beefy-e-bike-20-miles/

    And elteasprites simu is not worth a thing, reality is different from the models used

    Reality is always different from models because models can never have everything that reality has.
    But this does not mean that models aren't useful.
    Simulation can do a lot to tell you you're going in the right direction. >>>This can save a lot of time when you get to do it in reality.

    I stopped using it long ago (years)
    My stuff works.

    My sync separators worked too, back when I needed one.
    They weren't quite like yours, I think I got an idea from Video Handbook by someone, I forget who.


    ElTeaSprites is a bit like Hollowwood movies.
    Burb .. I mean Kirk.. well
    I do not question your genius,

    Well you should.
    Anyone who claims to be a genius might as well be telling you that they aren't.

    Just one more thing.
    Writing PC as peesee is fine if you're composing something like this: >>>https://www.google.com/search?q=I+halve+a+spelling+chequer
    But doing it repeatedly with every other word starts to make your perceived age go down.

    I use my spell shaker

    Your posts are getting ever more annoying and unreadable.

    Stop reading them.
    Your babble lately makes very little sense.
    aaybe you ate too much Raspberry?

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Liz Tuddenham@21:1/5 to All on Fri Nov 8 12:41:18 2024
    Jan Panteltje <alien@comet.invalid> wrote:

    [...] > https://panteltje.nl/pub/audio_90_degrees_phase_shifter_circuit_diagram_ IMG_6958.JPG

    Thst is a 90 degrees phase shifter over the speech audio range for
    generating I and Q signals for SSB modulation. design is not mine, used trimpots to test it :-)

    After reading through some back issues of 'Rad Com', I had been thinking
    along similar lines for generating SSB. I was also intrigued by the
    Weaver method and wondered if modern multi-stage filters between the
    inverted and non-inverted audio sidebands could reduce the audio notch
    effect and allow a wider frequency response.

    I let my licence lapse many years ago and had been thinking about taking
    it out again before the call-sign got issued to someone else. The
    problem is that they need to see my certificate to prove I passed the
    Radio Amateurs' Exam and I don't know where to find it.


    --
    ~ Liz Tuddenham ~
    (Remove the ".invalid"s and add ".co.uk" to reply)
    www.poppyrecords.co.uk

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Jan Panteltje@21:1/5 to Liz Tuddenham on Fri Nov 8 13:34:33 2024
    On a sunny day (Fri, 8 Nov 2024 12:41:18 +0000) it happened liz@poppyrecords.invalid.invalid (Liz Tuddenham) wrote in <1r2peuv.72nzt16pvcxmN%liz@poppyrecords.invalid.invalid>:

    Jan Panteltje <alien@comet.invalid> wrote:

    [...] > >https://panteltje.nl/pub/audio_90_degrees_phase_shifter_circuit_diagram_ >IMG_6958.JPG

    Thst is a 90 degrees phase shifter over the speech audio range for
    generating I and Q signals for SSB modulation. design is not mine, used
    trimpots to test it :-)

    After reading through some back issues of 'Rad Com', I had been thinking >along similar lines for generating SSB. I was also intrigued by the
    Weaver method and wondered if modern multi-stage filters between the
    inverted and non-inverted audio sidebands could reduce the audio notch >effect and allow a wider frequency response.

    In teh sixtoes I used a 9 MHz IFto make double sideband with a diode brige modulator
    and and a XF9B crystal filer to remove the unwanted sideband
    Had no license back then, all tubes, 250 W SSB with a Philips PE1/100
    https://www.radiomuseum.org/tubes/tube_pe1100.html
    Made QSO with a callsign I dreamed up..
    Was almost arrested, they were at the corner of the street locating me..

    Few years ago I got the A license, thought it was only fair as I was using stuff from ham radio
    https://panteltje.nl/panteltje/raspberry_pi_dvb-s_transmitter/
    and basically wanted to keep up with digital TV (when I left broadcasting it was still all analog).
    My license is still extended every year.
    But am not very active, have a Baofeng for 70 cm and some RF transceiver for shortwave.
    And the satellite stuff of course.
    But I will have to move the dish, after the cross the street houses had their roof insulated those became a bit higher and
    have their roofs filled with alu foil I think, I lost signal from the QO100 geostationary satellite....


    I let my licence lapse many years ago and had been thinking about taking
    it out again before the call-sign got issued to someone else. The
    problem is that they need to see my certificate to prove I passed the
    Radio Amateurs' Exam and I don't know where to find it.

    Well I have mine hanging on the wall, and keep some diplomas in a map somewhere.
    Also, in case of emergencies when all networks break down I can perhaps help using radio.
    Have enough backup power for that.

    There is a lot more...
    Have some old CB 27 MHz stuff too, CB was still licence free, worked South America on CB from here.

    It is a fine line, video from my drone's camera, who needs a license...
    https://panteltje.nl/pub/the_village_0_degrees.png
    https://panteltje.nl/panteltje/quadcopter/index.html
    Now you need a license here for a drone above some weight...
    And I am not allowed to fly a drone here at all as I am now close to a mil airport...

    A web of legislation... forms .. over time.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Cursitor Doom@21:1/5 to Liz Tuddenham on Fri Nov 8 17:44:41 2024
    On Fri, 8 Nov 2024 12:41:18 +0000, liz@poppyrecords.invalid.invalid
    (Liz Tuddenham) wrote:

    Jan Panteltje <alien@comet.invalid> wrote:

    [...] > >https://panteltje.nl/pub/audio_90_degrees_phase_shifter_circuit_diagram_ >IMG_6958.JPG

    Thst is a 90 degrees phase shifter over the speech audio range for
    generating I and Q signals for SSB modulation. design is not mine, used
    trimpots to test it :-)

    After reading through some back issues of 'Rad Com', I had been thinking >along similar lines for generating SSB. I was also intrigued by the
    Weaver method and wondered if modern multi-stage filters between the
    inverted and non-inverted audio sidebands could reduce the audio notch >effect and allow a wider frequency response.

    I let my licence lapse many years ago and had been thinking about taking
    it out again before the call-sign got issued to someone else. The
    problem is that they need to see my certificate to prove I passed the
    Radio Amateurs' Exam and I don't know where to find it.

    You'd ace it. It's been dumbed down so much over the years you'd have
    to be some kind of imbecile not to pass. I'm not sure if they still
    have it in two parts: technical and legal. However, the legal bit is
    pretty Janet & John as well.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Liz Tuddenham@21:1/5 to Cursitor Doom on Fri Nov 8 17:50:43 2024
    Cursitor Doom <cd@notformail.com> wrote:

    On Fri, 8 Nov 2024 12:41:18 +0000, liz@poppyrecords.invalid.invalid
    (Liz Tuddenham) wrote:

    Jan Panteltje <alien@comet.invalid> wrote:

    [...] > >https://panteltje.nl/pub/audio_90_degrees_phase_shifter_circuit_diagram_ >IMG_6958.JPG

    Thst is a 90 degrees phase shifter over the speech audio range for
    generating I and Q signals for SSB modulation. design is not mine, used
    trimpots to test it :-)

    After reading through some back issues of 'Rad Com', I had been thinking >along similar lines for generating SSB. I was also intrigued by the
    Weaver method and wondered if modern multi-stage filters between the >inverted and non-inverted audio sidebands could reduce the audio notch >effect and allow a wider frequency response.

    I let my licence lapse many years ago and had been thinking about taking
    it out again before the call-sign got issued to someone else. The
    problem is that they need to see my certificate to prove I passed the
    Radio Amateurs' Exam and I don't know where to find it.

    You'd ace it. It's been dumbed down so much over the years you'd have
    to be some kind of imbecile not to pass. I'm not sure if they still
    have it in two parts: technical and legal. However, the legal bit is
    pretty Janet & John as well.

    The Rad Com magazines from the 1960s include reprints of recently set
    exam papers, some of the questions are quite mathematical. In those
    days it was recognised that radio was just another branch of electrical engineeing, so you were expected to be able to do calculations on A.C.
    networks and understand PI tank circuits.

    --
    ~ Liz Tuddenham ~
    (Remove the ".invalid"s and add ".co.uk" to reply)
    www.poppyrecords.co.uk

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From ehsjr@21:1/5 to Liz Tuddenham on Fri Nov 8 16:43:26 2024
    On 11/8/2024 7:41 AM, Liz Tuddenham wrote:

    <snip>

    I let my licence lapse many years ago and had been thinking about taking
    it out again before the call-sign got issued to someone else. The
    problem is that they need to see my certificate to prove I passed the
    Radio Amateurs' Exam and I don't know where to find it.

    Maybe here:
    HamCall.net

    Ed

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Liz Tuddenham@21:1/5 to ehsjr on Fri Nov 8 22:33:45 2024
    ehsjr <ehsjr@verizon.net> wrote:

    On 11/8/2024 7:41 AM, Liz Tuddenham wrote:

    <snip>

    I let my licence lapse many years ago and had been thinking about taking
    it out again before the call-sign got issued to someone else. The
    problem is that they need to see my certificate to prove I passed the
    Radio Amateurs' Exam and I don't know where to find it.

    Maybe here:
    HamCall.net

    That site is really only or checking current licences, it doesn't even
    have a record of my old callsign. Ofcom wants to see the actual paper certificate I was awarded at the time.


    --
    ~ Liz Tuddenham ~
    (Remove the ".invalid"s and add ".co.uk" to reply)
    www.poppyrecords.co.uk

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Jan Panteltje@21:1/5 to Liz Tuddenham on Sat Nov 9 05:42:50 2024
    On a sunny day (Fri, 8 Nov 2024 22:33:45 +0000) it happened liz@poppyrecords.invalid.invalid (Liz Tuddenham) wrote in <1r2q6ij.1axeqad74faeaN%liz@poppyrecords.invalid.invalid>:

    ehsjr <ehsjr@verizon.net> wrote:

    On 11/8/2024 7:41 AM, Liz Tuddenham wrote:

    <snip>

    I let my licence lapse many years ago and had been thinking about taking >> > it out again before the call-sign got issued to someone else. The
    problem is that they need to see my certificate to prove I passed the
    Radio Amateurs' Exam and I don't know where to find it.

    Maybe here:
    HamCall.net

    That site is really only or checking current licences, it doesn't even
    have a record of my old callsign. Ofcom wants to see the actual paper >certificate I was awarded at the time.

    Over here you could do a request to the government agency that issued the licence for a paper copy I would think.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Liz Tuddenham@21:1/5 to Jan Panteltje on Sat Nov 9 09:51:09 2024
    Jan Panteltje <alien@comet.invalid> wrote:

    On a sunny day (Fri, 8 Nov 2024 22:33:45 +0000) it happened liz@poppyrecords.invalid.invalid (Liz Tuddenham) wrote in <1r2q6ij.1axeqad74faeaN%liz@poppyrecords.invalid.invalid>:

    ehsjr <ehsjr@verizon.net> wrote:

    On 11/8/2024 7:41 AM, Liz Tuddenham wrote:

    <snip>

    I let my licence lapse many years ago and had been thinking about taking >> > it out again before the call-sign got issued to someone else. The
    problem is that they need to see my certificate to prove I passed the
    Radio Amateurs' Exam and I don't know where to find it.

    Maybe here:
    HamCall.net

    That site is really only or checking current licences, it doesn't even
    have a record of my old callsign. Ofcom wants to see the actual paper >certificate I was awarded at the time.

    Over here you could do a request to the government agency that issued the
    licence for a paper copy I would think.

    In the UK, the exam was administered by the City & Guilds Institute and
    I took it a very long time ago.and there have been several major changes
    since then.


    --
    ~ Liz Tuddenham ~
    (Remove the ".invalid"s and add ".co.uk" to reply)
    www.poppyrecords.co.uk

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Liz Tuddenham@21:1/5 to Edward Rawde on Mon Nov 18 09:53:17 2024
    Edward Rawde <invalid@invalid.invalid> wrote:

    [...]

    Now approacing 90dB if you believe the simulation with with this
    experimental circuit. > You'll want to find something else to do while
    it simulates.
    How to inprove it further?

    At 1 Kc/s, a distortion figure of 90dB represents one cycle in 10^9, so
    you would have to run it for 1000 seconds before the startup transient
    became insignificant.


    --
    ~ Liz Tuddenham ~
    (Remove the ".invalid"s and add ".co.uk" to reply)
    www.poppyrecords.co.uk

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Edward Rawde@21:1/5 to Liz Tuddenham on Tue Nov 19 10:29:35 2024
    "Liz Tuddenham" <liz@poppyrecords.invalid.invalid> wrote in message news:1r37pyc.1bodve2fz5t4wN%liz@poppyrecords.invalid.invalid...
    Edward Rawde <invalid@invalid.invalid> wrote:

    [...]

    Now approacing 90dB if you believe the simulation with with this >>experimental circuit. > You'll want to find something else to do while
    it simulates.
    How to inprove it further?

    At 1 Kc/s, a distortion figure of 90dB represents one cycle in 10^9, so
    you would have to run it for 1000 seconds before the startup transient
    became insignificant.

    The startup transient was not included in the FFT but in any case the circuit has other issues so here is a circuit which works as
    intended.
    Harmonics are approaching 100dB down and 1k c/s is below 90dB.
    Simulate overnight then stop. It will be at about 250 seconds.
    Select roughly the last 50 seconds and FFT on current zoom extent.
    Number of data points may need increasing.

    What reality would say is anybody's guess and it has been pointed out that real measurements 100dB down may not be meaningful.

    We could probably have a discussion here about why c/s is better than Hz

    Version 4
    SHEET 1 2196 932
    WIRE -64 -576 -96 -576
    WIRE 48 -576 16 -576
    WIRE 128 -528 112 -528
    WIRE 208 -528 192 -528
    WIRE 288 -528 272 -528
    WIRE 368 -528 352 -528
    WIRE 448 -528 432 -528
    WIRE 528 -528 512 -528
    WIRE 640 -528 592 -528
    WIRE 640 -512 640 -528
    WIRE -32 -464 -32 -480
    WIRE 48 -448 48 -576
    WIRE 48 -448 0 -448
    WIRE -96 -432 -96 -576
    WIRE -64 -432 -96 -432
    WIRE 112 -416 112 -528
    WIRE 112 -416 0 -416
    WIRE 160 -416 112 -416
    WIRE 208 -416 160 -416
    WIRE 336 -416 288 -416
    WIRE 400 -416 336 -416
    WIRE 512 -416 400 -416
    WIRE 624 -416 512 -416
    WIRE -96 -384 -96 -432
    WIRE -32 -384 -32 -400
    WIRE 48 -368 48 -448
    WIRE 336 -368 336 -416
    WIRE 160 -352 160 -416
    WIRE 400 -352 400 -416
    WIRE 512 -288 512 -416
    WIRE 624 -288 624 -416
    WIRE -96 -272 -96 -304
    WIRE -96 -272 -192 -272
    WIRE -96 -240 -96 -272
    WIRE 48 -240 48 -288
    WIRE 160 -240 160 -288
    WIRE 336 -240 336 -288
    WIRE 400 -240 400 -288
    WIRE -192 -176 -192 -272
    WIRE -224 -128 -256 -128
    WIRE -96 -128 -96 -160
    WIRE -96 -128 -128 -128
    WIRE -80 -128 -96 -128
    WIRE 144 -128 -80 -128
    WIRE 288 -128 224 -128
    WIRE 352 -128 288 -128
    WIRE 512 -128 512 -224
    WIRE 512 -128 432 -128
    WIRE -256 -48 -256 -128
    WIRE -208 -48 -256 -48
    WIRE -80 -48 -80 -128
    WIRE -80 -48 -128 -48
    WIRE 288 -16 288 -128
    WIRE 288 -16 64 -16
    WIRE 352 -16 288 -16
    WIRE 512 -16 512 -128
    WIRE 512 -16 432 -16
    WIRE -256 0 -256 -48
    WIRE 144 48 144 32
    WIRE -272 96 -352 96
    WIRE -208 96 -272 96
    WIRE 64 96 64 -16
    WIRE 112 96 64 96
    WIRE 512 96 512 -16
    WIRE 512 96 272 96
    WIRE -32 128 -96 128
    WIRE 112 128 -32 128
    WIRE -352 144 -352 96
    WIRE 624 144 624 -224
    WIRE 656 144 624 144
    WIRE 752 144 720 144
    WIRE -208 160 -208 96
    WIRE -32 160 -32 128
    WIRE 112 160 64 160
    WIRE 624 160 624 144
    WIRE 624 160 272 160
    WIRE 752 176 752 144
    WIRE 144 224 144 208
    WIRE -32 256 -32 224
    WIRE 64 272 64 160
    WIRE 160 272 64 272
    WIRE 288 272 160 272
    WIRE 400 272 352 272
    WIRE 512 272 512 96
    WIRE 512 272 480 272
    WIRE 64 288 64 272
    WIRE 160 288 160 272
    WIRE 752 288 752 256
    WIRE 880 288 752 288
    WIRE 928 288 880 288
    WIRE -352 320 -352 224
    WIRE -352 320 -432 320
    WIRE 928 320 928 288
    WIRE -432 336 -432 320
    WIRE -352 336 -352 320
    WIRE -208 336 -208 224
    WIRE -208 336 -352 336
    WIRE -96 336 -96 128
    WIRE 64 384 64 368
    WIRE 160 384 160 352
    WIRE 160 384 64 384
    WIRE -352 416 -352 336
    WIRE 64 416 64 384
    WIRE -208 432 -208 336
    WIRE 192 432 144 432
    WIRE 304 432 272 432
    WIRE 384 432 368 432
    WIRE 928 432 928 400
    WIRE 512 448 512 272
    WIRE 624 448 624 160
    WIRE 288 544 288 528
    WIRE 384 560 384 432
    WIRE 384 560 320 560
    WIRE 624 560 624 512
    WIRE 624 560 384 560
    WIRE -96 576 -96 416
    WIRE -48 576 -96 576
    WIRE 32 576 -48 576
    WIRE 144 576 144 432
    WIRE 144 576 112 576
    WIRE 192 576 144 576
    WIRE 256 576 192 576
    WIRE -352 592 -352 496
    WIRE -272 592 -352 592
    WIRE -208 592 -208 496
    WIRE -208 592 -272 592
    WIRE 432 592 320 592
    WIRE 512 592 512 512
    WIRE 512 592 432 592
    WIRE 624 592 624 560
    WIRE 704 592 624 592
    WIRE -96 624 -96 576
    WIRE -48 624 -48 576
    WIRE 288 624 288 608
    WIRE 512 624 512 592
    WIRE 704 624 704 592
    WIRE 432 640 432 592
    WIRE 624 640 624 592
    WIRE -96 736 -96 688
    WIRE -48 736 -48 688
    WIRE -48 736 -96 736
    WIRE 432 736 432 704
    WIRE 512 736 512 704
    WIRE 512 736 432 736
    WIRE 624 736 624 704
    WIRE 624 736 512 736
    WIRE 704 736 704 704
    WIRE 704 736 624 736
    WIRE -96 768 -96 736
    WIRE 432 768 432 736
    FLAG -432 336 0
    FLAG 288 528 V+
    FLAG 144 224 V-
    FLAG -272 96 V+
    FLAG -272 592 V-
    FLAG 880 288 output
    FLAG 144 32 V+
    FLAG 288 624 V-
    FLAG 432 768 0
    FLAG -32 256 0
    FLAG -32 -480 V+
    FLAG -32 -384 V-
    FLAG -256 0 0
    FLAG 400 -240 0
    FLAG 160 -240 0
    FLAG 64 416 0
    FLAG 336 -240 0
    FLAG -96 768 0
    FLAG 192 576 dc-trim
    FLAG 640 -512 0
    FLAG 48 -240 0
    FLAG 928 432 0
    SYMBOL voltage -352 128 R0
    WINDOW 123 0 0 Left 0
    WINDOW 39 10 135 Left 2
    WINDOW 0 12 7 Left 2
    WINDOW 3 15 104 Left 2
    SYMATTR SpiceLine Rser=0.01
    SYMATTR InstName V1
    SYMATTR Value 6
    SYMBOL res 496 256 R90
    WINDOW 0 1 52 VBottom 2
    WINDOW 3 33 45 VTop 2
    SYMATTR InstName R11
    SYMATTR Value 10.5k
    SYMBOL cap 352 256 R90
    WINDOW 0 0 32 VBottom 2
    WINDOW 3 35 30 VTop 2
    SYMATTR InstName C8
    SYMATTR Value 15n
    SYMATTR SpiceLine V=16 Irms=271m Rser=0.594318 Lser=0 mfg="KEMET" pn="C0603C153K4RAC" type="X7R"
    SYMBOL res 240 -144 R90
    WINDOW 0 -1 46 VBottom 2
    WINDOW 3 35 56 VTop 2
    SYMATTR InstName R7
    SYMATTR Value 6.34k
    SYMBOL res 448 -144 R90
    WINDOW 0 -4 61 VBottom 2
    WINDOW 3 39 55 VTop 2
    SYMATTR InstName R8
    SYMATTR Value 13k
    SYMBOL njf -128 -176 R90
    WINDOW 0 -37 23 VRight 2
    WINDOW 3 -9 -3 VRight 2
    SYMATTR InstName J1
    SYMATTR Value J112
    SYMBOL voltage -352 400 R0
    WINDOW 123 0 0 Left 0
    WINDOW 39 10 135 Left 2
    WINDOW 0 10 0 Left 2
    WINDOW 3 15 104 Left 2
    SYMATTR SpiceLine Rser=0.01
    SYMATTR InstName V2
    SYMATTR Value 6
    SYMBOL res 48 272 R0
    WINDOW 3 36 65 Left 2
    SYMATTR Value 10.5k
    SYMATTR InstName R10
    SYMBOL schottky 496 -288 R0
    WINDOW 3 -17 -26 VRight 2
    SYMATTR Value BAS40HY
    SYMATTR InstName D1
    SYMATTR Description Diode
    SYMATTR Type diode
    SYMBOL res -112 -64 R90
    WINDOW 0 0 56 VBottom 2
    WINDOW 3 32 56 VTop 2
    SYMATTR InstName R3
    SYMATTR Value 82
    SYMBOL OpAmps\\LT1994 176 128 R0
    WINDOW 3 10 -65 Left 2
    WINDOW 0 11 -95 Left 2
    SYMATTR InstName U1
    SYMBOL schottky 528 448 M0
    WINDOW 3 52 -26 VRight 2
    WINDOW 0 -18 3 Left 2
    SYMATTR Value BAS40HY
    SYMATTR InstName D3
    SYMATTR Description Diode
    SYMATTR Type diode
    SYMBOL schottky 640 448 M0
    WINDOW 3 49 -26 VRight 2
    WINDOW 0 -21 4 Left 2
    SYMATTR Value BAS40HY
    SYMATTR InstName D4
    SYMATTR Description Diode
    SYMATTR Type diode
    SYMBOL res 528 608 M0
    WINDOW 3 25 87 Left 2
    SYMATTR Value 220k
    SYMATTR InstName R16
    SYMBOL res 720 608 M0
    WINDOW 3 27 87 Left 2
    SYMATTR Value 220k
    SYMATTR InstName R17
    SYMBOL res -112 -256 R0
    WINDOW 0 38 42 Left 2
    WINDOW 3 36 66 Left 2
    SYMATTR InstName R2
    SYMATTR Value 1k
    SYMBOL res 320 -384 R0
    WINDOW 0 -50 69 Left 2
    WINDOW 3 -54 98 Left 2
    SYMATTR InstName R13
    SYMATTR Value 220k
    SYMBOL res 448 -32 R90
    WINDOW 0 -4 61 VBottom 2
    WINDOW 3 39 55 VTop 2
    SYMATTR InstName R9
    SYMATTR Value 1.07Meg
    SYMBOL res -80 -288 R180
    WINDOW 0 40 70 Left 2
    WINDOW 3 45 42 Left 2
    SYMATTR InstName R1
    SYMATTR Value 1k
    SYMBOL res -80 432 R180
    WINDOW 0 36 76 Left 2
    WINDOW 3 36 40 Left 2
    SYMATTR InstName R5
    SYMATTR Value 33k
    SYMBOL res 176 416 M90
    WINDOW 0 0 56 VBottom 2
    WINDOW 3 32 56 VTop 2
    SYMATTR InstName R15
    SYMATTR Value 220
    SYMBOL res 16 560 M90
    WINDOW 0 0 56 VBottom 2
    WINDOW 3 32 56 VTop 2
    SYMATTR InstName R14
    SYMATTR Value 10k
    SYMBOL cap 176 352 R180
    WINDOW 0 -37 41 Left 2
    WINDOW 3 -50 13 Left 2
    SYMATTR InstName C7
    SYMATTR Value 15n
    SYMATTR SpiceLine V=16 Irms=271m Rser=0.594318 Lser=0 mfg="KEMET" pn="C0603C153K4RAC" type="X7R"
    SYMBOL cap 720 128 R90
    WINDOW 0 0 32 VBottom 2
    WINDOW 3 32 32 VTop 2
    SYMATTR InstName C13
    SYMATTR Value 100000n
    SYMATTR SpiceLine V=6.3 Irms=0 Rser=0.002 Lser=0 mfg="TDK" pn="C575OX5ROJI07M" type="X5R"
    SYMBOL res 736 160 R0
    SYMATTR InstName R18
    SYMATTR Value 600
    SYMBOL res 192 -400 R270
    WINDOW 0 35 55 VTop 2
    WINDOW 3 -6 55 VBottom 2
    SYMATTR InstName R12
    SYMATTR Value 220k
    SYMBOL cap 176 -352 M0
    WINDOW 0 -22 9 Left 2
    WINDOW 3 -75 48 Left 2
    SYMATTR InstName C6
    SYMATTR Value 10000n
    SYMATTR SpiceLine V=6.3 Irms=0 Rser=0 Lser=0 mfg="Murata" pn="GRM155R60J106ME15" type="X5R"
    SYMBOL cap 416 -352 M0
    WINDOW 0 -32 51 Left 2
    WINDOW 3 -72 7 Left 2
    SYMATTR InstName C10
    SYMATTR Value 10000n
    SYMATTR SpiceLine V=6.3 Irms=0 Rser=0 Lser=0 mfg="Murata" pn="GRM155R60J106ME15" type="X5R"
    SYMBOL cap 368 448 M270
    WINDOW 0 32 32 VTop 2
    WINDOW 3 0 32 VBottom 2
    SYMATTR InstName C9
    SYMATTR Value 10000n
    SYMATTR SpiceLine V=6.3 Irms=0 Rser=0 Lser=0 mfg="Murata" pn="GRM155R60J106ME15" type="X5R"
    SYMBOL cap 416 640 R0
    WINDOW 0 -37 6 Left 2
    WINDOW 3 -77 53 Left 2
    SYMATTR InstName C11
    SYMATTR Value 10000n
    SYMATTR SpiceLine V=6.3 Irms=0 Rser=0 Lser=0 mfg="Murata" pn="GRM155R60J106ME15" type="X5R"
    SYMBOL cap 608 640 R0
    WINDOW 0 -33 9 Left 2
    WINDOW 3 -72 51 Left 2
    SYMATTR InstName C12
    SYMATTR Value 10000n
    SYMATTR SpiceLine V=6.3 Irms=0 Rser=0 Lser=0 mfg="Murata" pn="GRM155R60J106ME15" type="X5R"
    SYMBOL cap -224 160 R0
    WINDOW 0 -22 9 Left 2
    WINDOW 3 -79 48 Left 2
    SYMATTR InstName C1
    SYMATTR Value 10000n
    SYMATTR SpiceLine V=6.3 Irms=0 Rser=0 Lser=0 mfg="Murata" pn="GRM155R60J106ME15" type="X5R"
    SYMBOL cap -224 432 R0
    WINDOW 0 -22 9 Left 2
    WINDOW 3 -75 50 Left 2
    SYMATTR InstName C2
    SYMATTR Value 10000n
    SYMATTR SpiceLine V=6.3 Irms=0 Rser=0 Lser=0 mfg="Murata" pn="GRM155R60J106ME15" type="X5R"
    SYMBOL cap -16 224 R180
    WINDOW 0 23 78 Left 2
    WINDOW 3 -74 78 Left 2
    SYMATTR InstName C4
    SYMATTR Value 10000n
    SYMATTR SpiceLine V=6.3 Irms=0 Rser=0 Lser=0 mfg="Murata" pn="GRM155R60J106ME15" type="X5R"
    SYMBOL diode -80 688 R180
    WINDOW 0 24 64 Left 2
    WINDOW 3 24 0 Left 2
    SYMATTR InstName D5
    SYMATTR Value 1N4148
    SYMBOL cap -64 688 M180
    WINDOW 0 24 56 Left 2
    WINDOW 3 24 8 Left 2
    SYMATTR InstName C5
    SYMATTR Value 1000n
    SYMATTR SpiceLine V=6.3 Irms=0 Rser=0 Lser=0 mfg="Murata" pn="GRM032R60J105ME05" type="X5R"
    SYMBOL OpAmps\\LT1678 -32 -432 M0
    WINDOW 0 -57 50 Left 2
    WINDOW 3 -47 89 Left 2
    SYMATTR InstName U2A
    SYMBOL diode 192 -544 R90
    WINDOW 0 0 32 VBottom 2
    WINDOW 3 32 32 VTop 2
    SYMATTR InstName D6
    SYMATTR Value 1N4148
    SYMBOL diode 272 -544 R90
    WINDOW 0 58 31 VBottom 2
    WINDOW 3 -28 34 VTop 2
    SYMATTR InstName D7
    SYMATTR Value 1N4148
    SYMBOL diode 352 -544 R90
    WINDOW 0 0 32 VBottom 2
    WINDOW 3 32 32 VTop 2
    SYMATTR InstName D8
    SYMATTR Value 1N4148
    SYMBOL diode 432 -544 R90
    WINDOW 0 58 27 VBottom 2
    WINDOW 3 -27 31 VTop 2
    SYMATTR InstName D9
    SYMATTR Value 1N4148
    SYMBOL diode 512 -544 R90
    WINDOW 0 0 32 VBottom 2
    WINDOW 3 32 32 VTop 2
    SYMATTR InstName D10
    SYMATTR Value 1N4148
    SYMBOL schottky 608 -288 R0
    WINDOW 3 -16 -25 VRight 2
    SYMATTR Value BAS40HY
    SYMATTR InstName D2
    SYMATTR Description Diode
    SYMATTR Type diode
    SYMBOL res -80 -560 R270
    WINDOW 0 33 55 VTop 2
    WINDOW 3 -3 55 VBottom 2
    SYMATTR InstName R4
    SYMATTR Value 10k
    SYMBOL res 32 -384 R0
    SYMATTR InstName R6
    SYMATTR Value 10k
    SYMBOL diode 592 -544 R90
    WINDOW 0 59 29 VBottom 2
    WINDOW 3 -25 30 VTop 2
    SYMATTR InstName D11
    SYMATTR Value 1N4148
    SYMBOL res 912 304 R0
    SYMATTR InstName R19
    SYMATTR Value 600
    SYMBOL OpAmps\\LT1678 288 576 M0
    WINDOW 0 21 -42 Left 2
    WINDOW 3 25 24 Left 2
    SYMATTR InstName U2B
    TEXT -448 632 Left 2 !.tran 0 1050s 50s startup

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Liz Tuddenham@21:1/5 to Edward Rawde on Tue Nov 19 16:12:26 2024
    Edward Rawde <invalid@invalid.invalid> wrote:

    "Liz Tuddenham" <liz@poppyrecords.invalid.invalid> wrote in message news:1r37pyc.1bodve2fz5t4wN%liz@poppyrecords.invalid.invalid...
    Edward
    Rawde <invalid@invalid.invalid> wrote: > > [...] >
    Now approacing 90dB if you believe the simulation with with this >>experimental circuit. > You'll want to find something else to do while
    it simulates.
    How to inprove it further?

    At 1 Kc/s, a distortion figure of 90dB represents one cycle in 10^9, so
    you would have to run it for 1000 seconds before the startup transient became insignificant.

    The startup transient was not included in the FFT but in any case the
    circuit has other issues so here is a circuit which works as intended. Harmonics are approaching 100dB down and 1k c/s is below 90dB. Simulate overnight then stop. It will be at about 250 seconds. Select roughly the
    last 50 seconds and FFT on current zoom extent. Number of data points may need increasing.

    The startup transient of the FFT would have to be included, so that may
    set a limit to the accuracy of the simulation measurements. Even if you
    start on a zero-axis crossing, you will get spurious results because of
    the finite length of the sample.

    This can be demonstrated by doing FFT on samples of fewer and fewer
    cycles from the middle of an apparently pure sinewave. As the sample
    length decreases, spurious harmonics begin to appear, even though they
    don't exist in reality.

    [...]
    We could probably have a discussion here about why c/s is better than Hz

    I don't know if it is 'better' but it suits me - and nobody seems to
    have any difficulty understanding it. By using a descriptive term,
    rather than a commemorative one, beginners find it easier to understand
    as it sounds less like jargon intended to exclude the uninitiated.

    (I have nothing against H.Hertz, it's just the principle that worries
    me).


    Version 4
    SHEET 1 2196 932
    WIRE -64 -576 -96 -576
    WIRE 48 -576 16 -576

    [...]

    I don't use Spice, so the rest doesn't convey anything to me.


    --
    ~ Liz Tuddenham ~
    (Remove the ".invalid"s and add ".co.uk" to reply)
    www.poppyrecords.co.uk

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Edward Rawde@21:1/5 to Liz Tuddenham on Tue Nov 19 11:47:00 2024
    "Liz Tuddenham" <liz@poppyrecords.invalid.invalid> wrote in message news:1r3a1m9.1lg1mngftnegwN%liz@poppyrecords.invalid.invalid...
    Edward Rawde <invalid@invalid.invalid> wrote:

    "Liz Tuddenham" <liz@poppyrecords.invalid.invalid> wrote in message
    news:1r37pyc.1bodve2fz5t4wN%liz@poppyrecords.invalid.invalid...
    Edward
    Rawde <invalid@invalid.invalid> wrote: > > [...] >
    Now approacing 90dB if you believe the simulation with with this
    experimental circuit. > You'll want to find something else to do while
    it simulates.
    How to inprove it further?

    At 1 Kc/s, a distortion figure of 90dB represents one cycle in 10^9, so
    you would have to run it for 1000 seconds before the startup transient
    became insignificant.

    The startup transient was not included in the FFT but in any case the
    circuit has other issues so here is a circuit which works as intended.
    Harmonics are approaching 100dB down and 1k c/s is below 90dB. Simulate
    overnight then stop. It will be at about 250 seconds. Select roughly the
    last 50 seconds and FFT on current zoom extent. Number of data points may
    need increasing.

    The startup transient of the FFT would have to be included, so that may
    set a limit to the accuracy of the simulation measurements. Even if you start on a zero-axis crossing, you will get spurious results because of
    the finite length of the sample.

    Yes I understand that. It's actually a sinewave multiplied by a rectangular function.
    That's why I try to use a sample length of many tens of seconds.
    A window function might help but then I'd have to decide which window to use.


    This can be demonstrated by doing FFT on samples of fewer and fewer
    cycles from the middle of an apparently pure sinewave. As the sample
    length decreases, spurious harmonics begin to appear, even though they
    don't exist in reality.

    [...]
    We could probably have a discussion here about why c/s is better than Hz

    I don't know if it is 'better' but it suits me - and nobody seems to
    have any difficulty understanding it. By using a descriptive term,
    rather than a commemorative one, beginners find it easier to understand
    as it sounds less like jargon intended to exclude the uninitiated.

    Yes that's why I sometimes prefer to use it.


    (I have nothing against H.Hertz, it's just the principle that worries
    me).

    I think it goes back to a time when some people thought they had more influence than they had, so we all had to use rectangular
    boxes for logic gates etc.



    Version 4
    SHEET 1 2196 932
    WIRE -64 -576 -96 -576
    WIRE 48 -576 16 -576

    [...]

    I don't use Spice, so the rest doesn't convey anything to me.

    I don't currently have a lab to play in so LTSpice is useful but there's no knowing how close a model of reality it is.



    --
    ~ Liz Tuddenham ~
    (Remove the ".invalid"s and add ".co.uk" to reply)
    www.poppyrecords.co.uk

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Jeroen Belleman@21:1/5 to Edward Rawde on Tue Nov 19 19:12:18 2024
    On 11/19/24 17:47, Edward Rawde wrote:
    "Liz Tuddenham" <liz@poppyrecords.invalid.invalid> wrote in message news:1r3a1m9.1lg1mngftnegwN%liz@poppyrecords.invalid.invalid...
    [...]

    The startup transient of the FFT would have to be included, so that may
    set a limit to the accuracy of the simulation measurements. Even if you
    start on a zero-axis crossing, you will get spurious results because of
    the finite length of the sample.

    Yes I understand that. It's actually a sinewave multiplied by a rectangular function.
    That's why I try to use a sample length of many tens of seconds.
    A window function might help but then I'd have to decide which window to use.


    This can be demonstrated by doing FFT on samples of fewer and fewer
    cycles from the middle of an apparently pure sinewave. As the sample
    length decreases, spurious harmonics begin to appear, even though they
    don't exist in reality.

    An FFT implicitly connects the end of the recording back to the
    beginning. It's sufficient that the number of periods is integer.

    Jeroen Belleman

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Edward Rawde@21:1/5 to Jeroen Belleman on Tue Nov 19 13:21:36 2024
    "Jeroen Belleman" <jeroen@nospam.please> wrote in message news:vhik6t$1v4ua$1@dont-email.me...
    On 11/19/24 17:47, Edward Rawde wrote:
    "Liz Tuddenham" <liz@poppyrecords.invalid.invalid> wrote in message
    news:1r3a1m9.1lg1mngftnegwN%liz@poppyrecords.invalid.invalid...
    [...]

    The startup transient of the FFT would have to be included, so that may
    set a limit to the accuracy of the simulation measurements. Even if you >>> start on a zero-axis crossing, you will get spurious results because of
    the finite length of the sample.

    Yes I understand that. It's actually a sinewave multiplied by a rectangular function.
    That's why I try to use a sample length of many tens of seconds.
    A window function might help but then I'd have to decide which window to use.


    This can be demonstrated by doing FFT on samples of fewer and fewer
    cycles from the middle of an apparently pure sinewave. As the sample
    length decreases, spurious harmonics begin to appear, even though they
    don't exist in reality.

    An FFT implicitly connects the end of the recording back to the
    beginning. It's sufficient that the number of periods is integer.

    It would be nice to detect zero crossings with positive slope as the start and end points but I'm not sure whether there's a way to
    do that in LTSpice.


    Jeroen Belleman


    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Joe Gwinn@21:1/5 to jeroen@nospam.please on Tue Nov 19 13:50:46 2024
    On Tue, 19 Nov 2024 19:12:18 +0100, Jeroen Belleman
    <jeroen@nospam.please> wrote:

    On 11/19/24 17:47, Edward Rawde wrote:
    "Liz Tuddenham" <liz@poppyrecords.invalid.invalid> wrote in message news:1r3a1m9.1lg1mngftnegwN%liz@poppyrecords.invalid.invalid...
    [...]

    The startup transient of the FFT would have to be included, so that may
    set a limit to the accuracy of the simulation measurements. Even if you >>> start on a zero-axis crossing, you will get spurious results because of
    the finite length of the sample.

    Yes I understand that. It's actually a sinewave multiplied by a rectangular function.
    That's why I try to use a sample length of many tens of seconds.
    A window function might help but then I'd have to decide which window to use.


    This can be demonstrated by doing FFT on samples of fewer and fewer
    cycles from the middle of an apparently pure sinewave. As the sample
    length decreases, spurious harmonics begin to appear, even though they
    don't exist in reality.

    An FFT implicitly connects the end of the recording back to the
    beginning. It's sufficient that the number of periods is integer.

    If testing with sine waves that all fit with an integral number of
    cycles per window, the FFT noise floor will be determined by the
    precision of the arithmetic used.

    But there is often a splice error at that join because the fit into
    the window is approximate, which is a good reason to use a window
    function. The default choice in the radar world is Taylor.

    Joe Gwinn

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From john larkin@21:1/5 to All on Tue Nov 19 12:16:05 2024
    On Tue, 19 Nov 2024 13:50:46 -0500, Joe Gwinn <joegwinn@comcast.net>
    wrote:

    On Tue, 19 Nov 2024 19:12:18 +0100, Jeroen Belleman
    <jeroen@nospam.please> wrote:

    On 11/19/24 17:47, Edward Rawde wrote:
    "Liz Tuddenham" <liz@poppyrecords.invalid.invalid> wrote in message news:1r3a1m9.1lg1mngftnegwN%liz@poppyrecords.invalid.invalid...
    [...]

    The startup transient of the FFT would have to be included, so that may >>>> set a limit to the accuracy of the simulation measurements. Even if you >>>> start on a zero-axis crossing, you will get spurious results because of >>>> the finite length of the sample.

    Yes I understand that. It's actually a sinewave multiplied by a rectangular function.
    That's why I try to use a sample length of many tens of seconds.
    A window function might help but then I'd have to decide which window to use.


    This can be demonstrated by doing FFT on samples of fewer and fewer
    cycles from the middle of an apparently pure sinewave. As the sample
    length decreases, spurious harmonics begin to appear, even though they >>>> don't exist in reality.

    An FFT implicitly connects the end of the recording back to the
    beginning. It's sufficient that the number of periods is integer.

    If testing with sine waves that all fit with an integral number of
    cycles per window, the FFT noise floor will be determined by the
    precision of the arithmetic used.

    But there is often a splice error at that join because the fit into
    the window is approximate, which is a good reason to use a window
    function. The default choice in the radar world is Taylor.

    Joe Gwinn

    I wouldn't trust LT Spice for simulating a low-distortion oscillator.

    Run a sim and zoom up on the top of some sine wave. It looks all
    segmented and ratty.

    I was just simulating something and had a KHz range loop oscillation
    that refused to be compensated. Turns out I had a BI behavioral
    current source driving an inductor, and that oscillated all by itself.
    A G current source does the same thing.

    At really low distortion, the opamp models can getcha too.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Joe Gwinn@21:1/5 to All on Tue Nov 19 16:55:11 2024
    On Tue, 19 Nov 2024 12:16:05 -0800, john larkin <jl@glen--canyon.com>
    wrote:

    On Tue, 19 Nov 2024 13:50:46 -0500, Joe Gwinn <joegwinn@comcast.net>
    wrote:

    On Tue, 19 Nov 2024 19:12:18 +0100, Jeroen Belleman
    <jeroen@nospam.please> wrote:

    On 11/19/24 17:47, Edward Rawde wrote:
    "Liz Tuddenham" <liz@poppyrecords.invalid.invalid> wrote in message news:1r3a1m9.1lg1mngftnegwN%liz@poppyrecords.invalid.invalid...
    [...]

    The startup transient of the FFT would have to be included, so that may >>>>> set a limit to the accuracy of the simulation measurements. Even if you >>>>> start on a zero-axis crossing, you will get spurious results because of >>>>> the finite length of the sample.

    Yes I understand that. It's actually a sinewave multiplied by a rectangular function.
    That's why I try to use a sample length of many tens of seconds.
    A window function might help but then I'd have to decide which window to use.


    This can be demonstrated by doing FFT on samples of fewer and fewer
    cycles from the middle of an apparently pure sinewave. As the sample >>>>> length decreases, spurious harmonics begin to appear, even though they >>>>> don't exist in reality.

    An FFT implicitly connects the end of the recording back to the >>>beginning. It's sufficient that the number of periods is integer.

    If testing with sine waves that all fit with an integral number of
    cycles per window, the FFT noise floor will be determined by the
    precision of the arithmetic used.

    But there is often a splice error at that join because the fit into
    the window is approximate, which is a good reason to use a window
    function. The default choice in the radar world is Taylor.

    Joe Gwinn

    I wouldn't trust LT Spice for simulating a low-distortion oscillator.

    Run a sim and zoom up on the top of some sine wave. It looks all
    segmented and ratty.

    I was just simulating something and had a KHz range loop oscillation
    that refused to be compensated. Turns out I had a BI behavioral
    current source driving an inductor, and that oscillated all by itself.
    A G current source does the same thing.

    At really low distortion, the opamp models can getcha too.

    Oh yeah. I don't use spice simulations unless I'm designing a
    circuit, which is rare these days.

    Mostly, I use Wolfram Mathematica, often with Bessel window functions
    (for phase linearity across the passband).

    Joe Gwinn

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Jan Panteltje@21:1/5 to joegwinn@comcast.net on Wed Nov 20 06:01:30 2024
    On a sunny day (Tue, 19 Nov 2024 16:55:11 -0500) it happened Joe Gwinn <joegwinn@comcast.net> wrote in <102qjjh5n2hr9b3mkmuibol68r4glc4fon@4ax.com>:

    On Tue, 19 Nov 2024 12:16:05 -0800, john larkin <jl@glen--canyon.com>
    wrote:

    On Tue, 19 Nov 2024 13:50:46 -0500, Joe Gwinn <joegwinn@comcast.net>
    wrote:

    On Tue, 19 Nov 2024 19:12:18 +0100, Jeroen Belleman >>><jeroen@nospam.please> wrote:

    On 11/19/24 17:47, Edward Rawde wrote:
    "Liz Tuddenham" <liz@poppyrecords.invalid.invalid> wrote in message
    news:1r3a1m9.1lg1mngftnegwN%liz@poppyrecords.invalid.invalid...
    [...]

    The startup transient of the FFT would have to be included, so that may >>>>>> set a limit to the accuracy of the simulation measurements. Even if you >>>>>> start on a zero-axis crossing, you will get spurious results because of >>>>>> the finite length of the sample.

    Yes I understand that. It's actually a sinewave multiplied by a rectangular function.
    That's why I try to use a sample length of many tens of seconds.
    A window function might help but then I'd have to decide which window to use.


    This can be demonstrated by doing FFT on samples of fewer and fewer >>>>>> cycles from the middle of an apparently pure sinewave. As the sample >>>>>> length decreases, spurious harmonics begin to appear, even though they >>>>>> don't exist in reality.

    An FFT implicitly connects the end of the recording back to the >>>>beginning. It's sufficient that the number of periods is integer.

    If testing with sine waves that all fit with an integral number of
    cycles per window, the FFT noise floor will be determined by the >>>precision of the arithmetic used.

    But there is often a splice error at that join because the fit into
    the window is approximate, which is a good reason to use a window >>>function. The default choice in the radar world is Taylor.

    Joe Gwinn

    I wouldn't trust LT Spice for simulating a low-distortion oscillator.

    Run a sim and zoom up on the top of some sine wave. It looks all
    segmented and ratty.

    I was just simulating something and had a KHz range loop oscillation
    that refused to be compensated. Turns out I had a BI behavioral
    current source driving an inductor, and that oscillated all by itself.
    A G current source does the same thing.

    At really low distortion, the opamp models can getcha too.

    Oh yeah. I don't use spice simulations unless I'm designing a
    circuit, which is rare these days.

    Mostly, I use Wolfram Mathematica, often with Bessel window functions
    (for phase linearity across the passband).

    Yep,
    and Wolfram Language and Mathematica are free on every Raspberry Pi computer:
    https://www.wolfram.com/raspberry-pi/

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Joe Gwinn@21:1/5 to All on Wed Nov 20 13:11:34 2024
    On Wed, 20 Nov 2024 06:01:30 GMT, Jan Panteltje <alien@comet.invalid>
    wrote:

    On a sunny day (Tue, 19 Nov 2024 16:55:11 -0500) it happened Joe Gwinn ><joegwinn@comcast.net> wrote in <102qjjh5n2hr9b3mkmuibol68r4glc4fon@4ax.com>:

    On Tue, 19 Nov 2024 12:16:05 -0800, john larkin <jl@glen--canyon.com> >>wrote:

    On Tue, 19 Nov 2024 13:50:46 -0500, Joe Gwinn <joegwinn@comcast.net> >>>wrote:

    On Tue, 19 Nov 2024 19:12:18 +0100, Jeroen Belleman >>>><jeroen@nospam.please> wrote:

    On 11/19/24 17:47, Edward Rawde wrote:
    "Liz Tuddenham" <liz@poppyrecords.invalid.invalid> wrote in message >>>>>> news:1r3a1m9.1lg1mngftnegwN%liz@poppyrecords.invalid.invalid... >>>>>[...]

    The startup transient of the FFT would have to be included, so that may >>>>>>> set a limit to the accuracy of the simulation measurements. Even if you
    start on a zero-axis crossing, you will get spurious results because of >>>>>>> the finite length of the sample.

    Yes I understand that. It's actually a sinewave multiplied by a rectangular function.
    That's why I try to use a sample length of many tens of seconds.
    A window function might help but then I'd have to decide which window to use.


    This can be demonstrated by doing FFT on samples of fewer and fewer >>>>>>> cycles from the middle of an apparently pure sinewave. As the sample >>>>>>> length decreases, spurious harmonics begin to appear, even though they >>>>>>> don't exist in reality.

    An FFT implicitly connects the end of the recording back to the >>>>>beginning. It's sufficient that the number of periods is integer.

    If testing with sine waves that all fit with an integral number of >>>>cycles per window, the FFT noise floor will be determined by the >>>>precision of the arithmetic used.

    But there is often a splice error at that join because the fit into
    the window is approximate, which is a good reason to use a window >>>>function. The default choice in the radar world is Taylor.

    Joe Gwinn

    I wouldn't trust LT Spice for simulating a low-distortion oscillator.

    Run a sim and zoom up on the top of some sine wave. It looks all >>>segmented and ratty.

    I was just simulating something and had a KHz range loop oscillation
    that refused to be compensated. Turns out I had a BI behavioral
    current source driving an inductor, and that oscillated all by itself.
    A G current source does the same thing.

    At really low distortion, the opamp models can getcha too.

    Oh yeah. I don't use spice simulations unless I'm designing a
    circuit, which is rare these days.

    Mostly, I use Wolfram Mathematica, often with Bessel window functions
    (for phase linearity across the passband).

    Yep,
    and Wolfram Language and Mathematica are free on every Raspberry Pi computer:
    <https://www.wolfram.com/raspberry-pi/>

    But if Raspberry Pi does achieve world domination, Wolfram will be
    forced to charge money for Mathematica there. So do it very slowly --
    maybe they won't notice in time.

    Joe

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Klaus Vestergaard Kragelund@21:1/5 to Edward Rawde on Thu Nov 21 22:50:55 2024
    On 04-11-2024 05:06, Edward Rawde wrote:
    Simulation isn't fast but if you let it complete and do an FFT on the last 30 seconds, it's 80dB down at all unwanted harmonics.
    There do however seem to be unwanted sidebands close in either side of 1KHz Any suggestions for improvement?


    EDN article, if it's any good I don't know:

    https://www.edn.com/a-simple-purely-analog-130db-thd-sine-wave-generator/?utm_source=newsletter&utm_campaign=link&utm_medium=EDNWeekly-20241121&oly_enc_id=1349J0830312F1F

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)