• another fast one-shot

    From john larkin@21:1/5 to All on Wed Jun 12 09:33:17 2024
    Here's another idea for a fast one-shot. This is the just-apply-money
    version and should get close to 1 ns pulse width and should easily
    trigger at 150 MHz.

    https://www.dropbox.com/scl/fi/1okfo8964bw5m53mjmxs6/Pecl_One_Shot_1.jpg?rlkey=dwus6qjyqsynl2rv6uje2xxtj&raw=1

    I can use the other half of the dual comparator elsewhere. This one
    has programmable hysteresis too.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Cursitor Doom@21:1/5 to john larkin on Wed Jun 12 17:22:49 2024
    On Wed, 12 Jun 2024 09:33:17 -0700, john larkin wrote:

    Here's another idea for a fast one-shot. This is the just-apply-money
    version and should get close to 1 ns pulse width and should easily
    trigger at 150 MHz.

    https://www.dropbox.com/scl/fi/1okfo8964bw5m53mjmxs6/
    Pecl_One_Shot_1.jpg?rlkey=dwus6qjyqsynl2rv6uje2xxtj&raw=1

    I can use the other half of the dual comparator elsewhere. This one has programmable hysteresis too.

    Exposing my contemptworthy ignorance here no doubt, but what exactly is it
    that is fast about this design, John? And what would its application be?

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From john larkin@21:1/5 to cd999666@notformail.com on Wed Jun 12 11:11:28 2024
    On Wed, 12 Jun 2024 17:22:49 -0000 (UTC), Cursitor Doom <cd999666@notformail.com> wrote:

    On Wed, 12 Jun 2024 09:33:17 -0700, john larkin wrote:

    Here's another idea for a fast one-shot. This is the just-apply-money
    version and should get close to 1 ns pulse width and should easily
    trigger at 150 MHz.

    https://www.dropbox.com/scl/fi/1okfo8964bw5m53mjmxs6/ >Pecl_One_Shot_1.jpg?rlkey=dwus6qjyqsynl2rv6uje2xxtj&raw=1

    I can use the other half of the dual comparator elsewhere. This one has
    programmable hysteresis too.

    Exposing my contemptworthy ignorance here no doubt, but what exactly is it >that is fast about this design, John? And what would its application be?

    It would have a leading-edge prop delay of 350 ps, a minimum pulse
    width just over 1 ns, and would easily trigger at 150 MHz. Integrated one-shots, xxx123 types, are always terrible, even the obsolete ECL
    ones.

    It would be a programmable delay in a number of possible products,
    including some optical modulators. Just playing right now.

    More dollars could certainly do something faster, but as long as
    customers connect boxes with cables, faster isn't worth a lot. Light
    just moves too slow.

    Any suggestions for a faster one-shot?

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From bitrex@21:1/5 to john larkin on Wed Jun 12 16:44:14 2024
    On 6/12/2024 2:11 PM, john larkin wrote:
    On Wed, 12 Jun 2024 17:22:49 -0000 (UTC), Cursitor Doom <cd999666@notformail.com> wrote:

    On Wed, 12 Jun 2024 09:33:17 -0700, john larkin wrote:

    Here's another idea for a fast one-shot. This is the just-apply-money
    version and should get close to 1 ns pulse width and should easily
    trigger at 150 MHz.

    https://www.dropbox.com/scl/fi/1okfo8964bw5m53mjmxs6/
    Pecl_One_Shot_1.jpg?rlkey=dwus6qjyqsynl2rv6uje2xxtj&raw=1

    I can use the other half of the dual comparator elsewhere. This one has
    programmable hysteresis too.

    Exposing my contemptworthy ignorance here no doubt, but what exactly is it >> that is fast about this design, John? And what would its application be?

    It would have a leading-edge prop delay of 350 ps, a minimum pulse
    width just over 1 ns, and would easily trigger at 150 MHz. Integrated one-shots, xxx123 types, are always terrible, even the obsolete ECL
    ones.

    It would be a programmable delay in a number of possible products,
    including some optical modulators. Just playing right now.

    More dollars could certainly do something faster, but as long as
    customers connect boxes with cables, faster isn't worth a lot. Light
    just moves too slow.

    Any suggestions for a faster one-shot?


    What about connecting the + of the RC to Q to speed up the discharge

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From john larkin@21:1/5 to bitrex on Wed Jun 12 14:21:13 2024
    On Wed, 12 Jun 2024 16:44:14 -0400, bitrex <user@example.net> wrote:

    On 6/12/2024 2:11 PM, john larkin wrote:
    On Wed, 12 Jun 2024 17:22:49 -0000 (UTC), Cursitor Doom
    <cd999666@notformail.com> wrote:

    On Wed, 12 Jun 2024 09:33:17 -0700, john larkin wrote:

    Here's another idea for a fast one-shot. This is the just-apply-money
    version and should get close to 1 ns pulse width and should easily
    trigger at 150 MHz.

    https://www.dropbox.com/scl/fi/1okfo8964bw5m53mjmxs6/
    Pecl_One_Shot_1.jpg?rlkey=dwus6qjyqsynl2rv6uje2xxtj&raw=1

    I can use the other half of the dual comparator elsewhere. This one has >>>> programmable hysteresis too.

    Exposing my contemptworthy ignorance here no doubt, but what exactly is it >>> that is fast about this design, John? And what would its application be?

    It would have a leading-edge prop delay of 350 ps, a minimum pulse
    width just over 1 ns, and would easily trigger at 150 MHz. Integrated
    one-shots, xxx123 types, are always terrible, even the obsolete ECL
    ones.

    It would be a programmable delay in a number of possible products,
    including some optical modulators. Just playing right now.

    More dollars could certainly do something faster, but as long as
    customers connect boxes with cables, faster isn't worth a lot. Light
    just moves too slow.

    Any suggestions for a faster one-shot?


    What about connecting the + of the RC to Q to speed up the discharge

    Pecl only swings about 0.8 volts, up close to Vcc, so it wouldn't help
    much. That phemt turns on pretty hard, maybe 100 mA with Rds-on a
    couple of ohms.

    Speeding up the discharge would improve rep-rate but wouldn't affect
    minimum pulse width. I'd need a faster comparator for that, or some
    different architecture.

    The phemt gate driver is a little scary but will work if done
    carefully.

    I could give up a bit of speed and do this in CMOS. There's a 1 ns
    TinyLogic flop that's 36 cents.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Cursitor Doom@21:1/5 to john larkin on Wed Jun 12 22:18:43 2024
    On Wed, 12 Jun 2024 11:11:28 -0700, john larkin wrote:

    On Wed, 12 Jun 2024 17:22:49 -0000 (UTC), Cursitor Doom <cd999666@notformail.com> wrote:

    On Wed, 12 Jun 2024 09:33:17 -0700, john larkin wrote:

    Here's another idea for a fast one-shot. This is the just-apply-money
    version and should get close to 1 ns pulse width and should easily
    trigger at 150 MHz.

    https://www.dropbox.com/scl/fi/1okfo8964bw5m53mjmxs6/ >>Pecl_One_Shot_1.jpg?rlkey=dwus6qjyqsynl2rv6uje2xxtj&raw=1

    I can use the other half of the dual comparator elsewhere. This one
    has programmable hysteresis too.

    Exposing my contemptworthy ignorance here no doubt, but what exactly is
    it that is fast about this design, John? And what would its application
    be?

    It would have a leading-edge prop delay of 350 ps, a minimum pulse width
    just over 1 ns, and would easily trigger at 150 MHz. Integrated
    one-shots, xxx123 types, are always terrible, even the obsolete ECL
    ones.

    It would be a programmable delay in a number of possible products,
    including some optical modulators. Just playing right now.

    More dollars could certainly do something faster, but as long as
    customers connect boxes with cables, faster isn't worth a lot. Light
    just moves too slow.

    Any suggestions for a faster one-shot?

    Not from me! I couldn't even design a PID controlled PLL without recourse
    to the 'net.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Bill Sloman@21:1/5 to john larkin on Thu Jun 13 16:03:04 2024
    On 13/06/2024 4:11 am, john larkin wrote:
    On Wed, 12 Jun 2024 17:22:49 -0000 (UTC), Cursitor Doom <cd999666@notformail.com> wrote:

    On Wed, 12 Jun 2024 09:33:17 -0700, john larkin wrote:

    Here's another idea for a fast one-shot. This is the just-apply-money
    version and should get close to 1 ns pulse width and should easily
    trigger at 150 MHz.

    https://www.dropbox.com/scl/fi/1okfo8964bw5m53mjmxs6/
    Pecl_One_Shot_1.jpg?rlkey=dwus6qjyqsynl2rv6uje2xxtj&raw=1

    I can use the other half of the dual comparator elsewhere. This one has
    programmable hysteresis too.

    Exposing my contemptworthy ignorance here no doubt, but what exactly is it >> that is fast about this design, John? And what would its application be?

    It would have a leading-edge prop delay of 350 ps, a minimum pulse
    width just over 1 ns, and would easily trigger at 150 MHz. Integrated one-shots, xxx123 types, are always terrible, even the obsolete ECL
    ones.

    It would be a programmable delay in a number of possible products,
    including some optical modulators. Just playing right now.

    More dollars could certainly do something faster, but as long as
    customers connect boxes with cables, faster isn't worth a lot. Light
    just moves too slow.

    Any suggestions for a faster one-shot?

    Version 4
    SHEET 1 2924 1040
    WIRE -592 -720 -768 -720
    WIRE 128 -720 -592 -720
    WIRE 304 -720 128 -720
    WIRE 768 -720 304 -720
    WIRE 976 -720 768 -720
    WIRE 1488 -576 1488 -720
    WIRE 128 -560 128 -720
    WIRE 304 -560 304 -720
    WIRE 768 -560 768 -720
    WIRE -592 -384 -592 -720
    WIRE 1072 -368 1072 -400
    WIRE 768 -320 768 -480
    WIRE 960 -320 768 -320
    WIRE 1008 -320 960 -320
    WIRE 128 -288 128 -480
    WIRE 176 -288 128 -288
    WIRE 576 -288 240 -288
    WIRE 768 -208 768 -320
    WIRE 304 -160 304 -480
    WIRE 400 -160 304 -160
    WIRE 576 -160 576 -288
    WIRE 576 -160 480 -160
    WIRE 640 -160 576 -160
    WIRE 704 -160 640 -160
    WIRE -768 -64 -768 -720
    WIRE 128 48 128 -288
    WIRE -272 96 -432 96
    WIRE 64 96 -192 96
    WIRE 640 128 640 -160
    WIRE 304 160 304 -160
    WIRE -432 240 -432 96
    WIRE -768 416 -768 16
    WIRE -768 416 -880 416
    WIRE -736 416 -768 416
    WIRE -592 416 -592 -320
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    WIRE -432 416 -432 320
    WIRE -432 416 -496 416
    WIRE 640 416 640 208
    WIRE 640 416 -432 416
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    WIRE 128 464 128 144
    WIRE 768 464 768 -112
    WIRE 768 464 128 464
    WIRE -880 496 -880 416
    WIRE 768 496 768 464
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    WIRE -736 656 -736 640
    WIRE -736 944 -736 720
    WIRE -496 944 -496 704
    WIRE -496 944 -736 944
    WIRE 304 944 304 240
    WIRE 304 944 -496 944
    WIRE 768 944 768 576
    WIRE 768 944 304 944
    WIRE 1760 944 768 944
    FLAG -880 496 0
    FLAG 960 -320 out
    SYMBOL npn 64 48 R0
    SYMATTR InstName Q1
    SYMATTR Value BFR92A
    SYMBOL npn 704 -208 R0
    SYMATTR InstName Q2
    SYMATTR Value BFR92A
    SYMBOL voltage -768 -80 R0
    WINDOW 123 0 0 Left 0
    WINDOW 39 24 44 Left 2
    SYMATTR SpiceLine Rser=0.1
    SYMATTR InstName V1
    SYMATTR Value 5.0
    SYMBOL voltage -736 624 R0
    WINDOW 123 0 0 Left 0
    WINDOW 39 24 44 Left 2
    SYMATTR SpiceLine Rser=0.1
    SYMATTR InstName V2
    SYMATTR Value 4.5
    SYMBOL voltage -432 224 R0
    WINDOW 123 0 0 Left 0
    WINDOW 39 0 0 Left 0
    SYMATTR InstName V3
    SYMATTR Value PULSE(0 0.2 1n 300p 300p 100p 200n 2)
    SYMBOL res -176 80 R90
    WINDOW 0 0 56 VBottom 2
    WINDOW 3 32 56 VTop 2
    SYMATTR InstName R1
    SYMATTR Value 22
    SYMBOL res 752 480 R0
    SYMATTR InstName R3
    SYMATTR Value 360
    SYMBOL res 112 -576 R0
    SYMATTR InstName R4
    SYMATTR Value 180
    SYMBOL res 624 112 R0
    SYMATTR InstName R5
    SYMATTR Value 43
    SYMBOL res 752 -576 R0
    SYMATTR InstName R6
    SYMATTR Value 180
    SYMBOL res 288 -576 R0
    SYMATTR InstName R2
    SYMATTR Value 1k
    SYMBOL cap 240 -304 R90
    WINDOW 0 0 32 VBottom 2
    WINDOW 3 32 32 VTop 2
    SYMATTR InstName C1
    SYMATTR Value 3.3p
    SYMBOL res 288 144 R0
    SYMATTR InstName R7
    SYMATTR Value 1k2
    SYMBOL res 496 -176 R90
    WINDOW 0 0 56 VBottom 2
    WINDOW 3 32 56 VTop 2
    SYMATTR InstName R13
    SYMATTR Value 43
    SYMBOL cap -608 -384 R0
    SYMATTR InstName C3
    SYMATTR Value 10n
    SYMBOL cap -512 640 R0
    SYMATTR InstName C4
    SYMATTR Value 10n
    TEXT -272 1000 Left 2 !.model BFR92A NPN(IS=0.1213E-15 VAF=30 BF=94.73 IKF=0.46227 XTB=0 BR=10.729 CJC=946.47E-15 CJE=10.416E-15 TR=1.2744E-9 TF=26.796E-12 ITF=0.0044601 VTF=0.32861 XTF=0.3817 RB=14.998
    RC=0.13793 RE=0.29088 Vceo=15 Icrating=4m mfg=Infineon)
    TEXT -904 1024 Left 2 !.tran 0 500n 0

    It's just a two transistor emitter-coupled monostable, but with the two transistors as BFR92's run at 10mA, it produces 1nsec pulse without fuss.

    Finding the broad-band PNPs to let you translate the output pulse to a
    useful voltage level is tricky. Phil Hobbs has told us that there is a
    least one still in production and available.

    --
    Bill Sloman, Sydney

    --
    This email has been checked for viruses by Norton antivirus software. www.norton.com

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From john larkin@21:1/5 to All on Thu Jun 13 08:31:06 2024
    On Thu, 13 Jun 2024 16:03:04 +1000, Bill Sloman <bill.sloman@ieee.org>
    wrote:

    On 13/06/2024 4:11 am, john larkin wrote:
    On Wed, 12 Jun 2024 17:22:49 -0000 (UTC), Cursitor Doom
    <cd999666@notformail.com> wrote:

    On Wed, 12 Jun 2024 09:33:17 -0700, john larkin wrote:

    Here's another idea for a fast one-shot. This is the just-apply-money
    version and should get close to 1 ns pulse width and should easily
    trigger at 150 MHz.

    https://www.dropbox.com/scl/fi/1okfo8964bw5m53mjmxs6/
    Pecl_One_Shot_1.jpg?rlkey=dwus6qjyqsynl2rv6uje2xxtj&raw=1

    I can use the other half of the dual comparator elsewhere. This one has >>>> programmable hysteresis too.

    Exposing my contemptworthy ignorance here no doubt, but what exactly is it >>> that is fast about this design, John? And what would its application be?

    It would have a leading-edge prop delay of 350 ps, a minimum pulse
    width just over 1 ns, and would easily trigger at 150 MHz. Integrated
    one-shots, xxx123 types, are always terrible, even the obsolete ECL
    ones.

    It would be a programmable delay in a number of possible products,
    including some optical modulators. Just playing right now.

    More dollars could certainly do something faster, but as long as
    customers connect boxes with cables, faster isn't worth a lot. Light
    just moves too slow.

    Any suggestions for a faster one-shot?

    Version 4
    SHEET 1 2924 1040
    WIRE -592 -720 -768 -720
    WIRE 128 -720 -592 -720
    WIRE 304 -720 128 -720
    WIRE 768 -720 304 -720
    WIRE 976 -720 768 -720
    WIRE 1488 -576 1488 -720
    WIRE 128 -560 128 -720
    WIRE 304 -560 304 -720
    WIRE 768 -560 768 -720
    WIRE -592 -384 -592 -720
    WIRE 1072 -368 1072 -400
    WIRE 768 -320 768 -480
    WIRE 960 -320 768 -320
    WIRE 1008 -320 960 -320
    WIRE 128 -288 128 -480
    WIRE 176 -288 128 -288
    WIRE 576 -288 240 -288
    WIRE 768 -208 768 -320
    WIRE 304 -160 304 -480
    WIRE 400 -160 304 -160
    WIRE 576 -160 576 -288
    WIRE 576 -160 480 -160
    WIRE 640 -160 576 -160
    WIRE 704 -160 640 -160
    WIRE -768 -64 -768 -720
    WIRE 128 48 128 -288
    WIRE -272 96 -432 96
    WIRE 64 96 -192 96
    WIRE 640 128 640 -160
    WIRE 304 160 304 -160
    WIRE -432 240 -432 96
    WIRE -768 416 -768 16
    WIRE -768 416 -880 416
    WIRE -736 416 -768 416
    WIRE -592 416 -592 -320
    WIRE -592 416 -736 416
    WIRE -496 416 -592 416
    WIRE -432 416 -432 320
    WIRE -432 416 -496 416
    WIRE 640 416 640 208
    WIRE 640 416 -432 416
    WIRE 1072 416 640 416
    WIRE 128 464 128 144
    WIRE 768 464 768 -112
    WIRE 768 464 128 464
    WIRE -880 496 -880 416
    WIRE 768 496 768 464
    WIRE -736 640 -736 416
    WIRE -496 640 -496 416
    WIRE -736 656 -736 640
    WIRE -736 944 -736 720
    WIRE -496 944 -496 704
    WIRE -496 944 -736 944
    WIRE 304 944 304 240
    WIRE 304 944 -496 944
    WIRE 768 944 768 576
    WIRE 768 944 304 944
    WIRE 1760 944 768 944
    FLAG -880 496 0
    FLAG 960 -320 out
    SYMBOL npn 64 48 R0
    SYMATTR InstName Q1
    SYMATTR Value BFR92A
    SYMBOL npn 704 -208 R0
    SYMATTR InstName Q2
    SYMATTR Value BFR92A
    SYMBOL voltage -768 -80 R0
    WINDOW 123 0 0 Left 0
    WINDOW 39 24 44 Left 2
    SYMATTR SpiceLine Rser=0.1
    SYMATTR InstName V1
    SYMATTR Value 5.0
    SYMBOL voltage -736 624 R0
    WINDOW 123 0 0 Left 0
    WINDOW 39 24 44 Left 2
    SYMATTR SpiceLine Rser=0.1
    SYMATTR InstName V2
    SYMATTR Value 4.5
    SYMBOL voltage -432 224 R0
    WINDOW 123 0 0 Left 0
    WINDOW 39 0 0 Left 0
    SYMATTR InstName V3
    SYMATTR Value PULSE(0 0.2 1n 300p 300p 100p 200n 2)
    SYMBOL res -176 80 R90
    WINDOW 0 0 56 VBottom 2
    WINDOW 3 32 56 VTop 2
    SYMATTR InstName R1
    SYMATTR Value 22
    SYMBOL res 752 480 R0
    SYMATTR InstName R3
    SYMATTR Value 360
    SYMBOL res 112 -576 R0
    SYMATTR InstName R4
    SYMATTR Value 180
    SYMBOL res 624 112 R0
    SYMATTR InstName R5
    SYMATTR Value 43
    SYMBOL res 752 -576 R0
    SYMATTR InstName R6
    SYMATTR Value 180
    SYMBOL res 288 -576 R0
    SYMATTR InstName R2
    SYMATTR Value 1k
    SYMBOL cap 240 -304 R90
    WINDOW 0 0 32 VBottom 2
    WINDOW 3 32 32 VTop 2
    SYMATTR InstName C1
    SYMATTR Value 3.3p
    SYMBOL res 288 144 R0
    SYMATTR InstName R7
    SYMATTR Value 1k2
    SYMBOL res 496 -176 R90
    WINDOW 0 0 56 VBottom 2
    WINDOW 3 32 56 VTop 2
    SYMATTR InstName R13
    SYMATTR Value 43
    SYMBOL cap -608 -384 R0
    SYMATTR InstName C3
    SYMATTR Value 10n
    SYMBOL cap -512 640 R0
    SYMATTR InstName C4
    SYMATTR Value 10n
    TEXT -272 1000 Left 2 !.model BFR92A NPN(IS=0.1213E-15 VAF=30 BF=94.73 >IKF=0.46227 XTB=0 BR=10.729 CJC=946.47E-15 CJE=10.416E-15 TR=1.2744E-9 >TF=26.796E-12 ITF=0.0044601 VTF=0.32861 XTF=0.3817 RB=14.998
    RC=0.13793 RE=0.29088 Vceo=15 Icrating=4m mfg=Infineon)
    TEXT -904 1024 Left 2 !.tran 0 500n 0

    It's just a two transistor emitter-coupled monostable, but with the two >transistors as BFR92's run at 10mA, it produces 1nsec pulse without fuss.

    Finding the broad-band PNPs to let you translate the output pulse to a
    useful voltage level is tricky. Phil Hobbs has told us that there is a
    least one still in production and available.

    --
    Bill Sloman, Sydney

    What a mess. The output pulse width just follows the input pulse
    width. Unless you change C1, in which case it oscillates.

    It's ugly too. Obviously frobbed until it seems to work.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From piglet@21:1/5 to Bill Sloman on Fri Jun 14 19:02:11 2024
    On 13/06/2024 07:03, Bill Sloman wrote:
    On 13/06/2024 4:11 am, john larkin wrote:
    On Wed, 12 Jun 2024 17:22:49 -0000 (UTC), Cursitor Doom
    <cd999666@notformail.com> wrote:

    On Wed, 12 Jun 2024 09:33:17 -0700, john larkin wrote:

    Here's another idea for a fast one-shot. This is the just-apply-money
    version and should get close to 1 ns pulse width and should easily
    trigger at 150 MHz.

    https://www.dropbox.com/scl/fi/1okfo8964bw5m53mjmxs6/
    Pecl_One_Shot_1.jpg?rlkey=dwus6qjyqsynl2rv6uje2xxtj&raw=1

    I can use the other half of the dual comparator elsewhere. This one has >>>> programmable hysteresis too.

    Exposing my contemptworthy ignorance here no doubt, but what exactly
    is it
    that is fast about this design, John? And what would its application be?

    It would have a leading-edge prop delay of 350 ps, a minimum pulse
    width just over 1 ns, and would easily trigger at 150 MHz. Integrated
    one-shots, xxx123 types, are always terrible, even the obsolete ECL
    ones.

    It would be a programmable delay in a number of possible products,
    including some optical modulators. Just playing right now.

    More dollars could certainly do something faster, but as long as
    customers connect boxes with cables, faster isn't worth a lot. Light
    just moves too slow.

    Any suggestions for a faster one-shot?

    Version 4
    SHEET 1 2924 1040
    WIRE -592 -720 -768 -720
    WIRE 128 -720 -592 -720
    WIRE 304 -720 128 -720
    WIRE 768 -720 304 -720
    WIRE 976 -720 768 -720
    WIRE 1488 -576 1488 -720
    WIRE 128 -560 128 -720
    WIRE 304 -560 304 -720
    WIRE 768 -560 768 -720
    WIRE -592 -384 -592 -720
    WIRE 1072 -368 1072 -400
    WIRE 768 -320 768 -480
    WIRE 960 -320 768 -320
    WIRE 1008 -320 960 -320
    WIRE 128 -288 128 -480
    WIRE 176 -288 128 -288
    WIRE 576 -288 240 -288
    WIRE 768 -208 768 -320
    WIRE 304 -160 304 -480
    WIRE 400 -160 304 -160
    WIRE 576 -160 576 -288
    WIRE 576 -160 480 -160
    WIRE 640 -160 576 -160
    WIRE 704 -160 640 -160
    WIRE -768 -64 -768 -720
    WIRE 128 48 128 -288
    WIRE -272 96 -432 96
    WIRE 64 96 -192 96
    WIRE 640 128 640 -160
    WIRE 304 160 304 -160
    WIRE -432 240 -432 96
    WIRE -768 416 -768 16
    WIRE -768 416 -880 416
    WIRE -736 416 -768 416
    WIRE -592 416 -592 -320
    WIRE -592 416 -736 416
    WIRE -496 416 -592 416
    WIRE -432 416 -432 320
    WIRE -432 416 -496 416
    WIRE 640 416 640 208
    WIRE 640 416 -432 416
    WIRE 1072 416 640 416
    WIRE 128 464 128 144
    WIRE 768 464 768 -112
    WIRE 768 464 128 464
    WIRE -880 496 -880 416
    WIRE 768 496 768 464
    WIRE -736 640 -736 416
    WIRE -496 640 -496 416
    WIRE -736 656 -736 640
    WIRE -736 944 -736 720
    WIRE -496 944 -496 704
    WIRE -496 944 -736 944
    WIRE 304 944 304 240
    WIRE 304 944 -496 944
    WIRE 768 944 768 576
    WIRE 768 944 304 944
    WIRE 1760 944 768 944
    FLAG -880 496 0
    FLAG 960 -320 out
    SYMBOL npn 64 48 R0
    SYMATTR InstName Q1
    SYMATTR Value BFR92A
    SYMBOL npn 704 -208 R0
    SYMATTR InstName Q2
    SYMATTR Value BFR92A
    SYMBOL voltage -768 -80 R0
    WINDOW 123 0 0 Left 0
    WINDOW 39 24 44 Left 2
    SYMATTR SpiceLine Rser=0.1
    SYMATTR InstName V1
    SYMATTR Value 5.0
    SYMBOL voltage -736 624 R0
    WINDOW 123 0 0 Left 0
    WINDOW 39 24 44 Left 2
    SYMATTR SpiceLine Rser=0.1
    SYMATTR InstName V2
    SYMATTR Value 4.5
    SYMBOL voltage -432 224 R0
    WINDOW 123 0 0 Left 0
    WINDOW 39 0 0 Left 0
    SYMATTR InstName V3
    SYMATTR Value PULSE(0 0.2 1n 300p 300p 100p 200n 2)
    SYMBOL res -176 80 R90
    WINDOW 0 0 56 VBottom 2
    WINDOW 3 32 56 VTop 2
    SYMATTR InstName R1
    SYMATTR Value 22
    SYMBOL res 752 480 R0
    SYMATTR InstName R3
    SYMATTR Value 360
    SYMBOL res 112 -576 R0
    SYMATTR InstName R4
    SYMATTR Value 180
    SYMBOL res 624 112 R0
    SYMATTR InstName R5
    SYMATTR Value 43
    SYMBOL res 752 -576 R0
    SYMATTR InstName R6
    SYMATTR Value 180
    SYMBOL res 288 -576 R0
    SYMATTR InstName R2
    SYMATTR Value 1k
    SYMBOL cap 240 -304 R90
    WINDOW 0 0 32 VBottom 2
    WINDOW 3 32 32 VTop 2
    SYMATTR InstName C1
    SYMATTR Value 3.3p
    SYMBOL res 288 144 R0
    SYMATTR InstName R7
    SYMATTR Value 1k2
    SYMBOL res 496 -176 R90
    WINDOW 0 0 56 VBottom 2
    WINDOW 3 32 56 VTop 2
    SYMATTR InstName R13
    SYMATTR Value 43
    SYMBOL cap -608 -384 R0
    SYMATTR InstName C3
    SYMATTR Value 10n
    SYMBOL cap -512 640 R0
    SYMATTR InstName C4
    SYMATTR Value 10n
    TEXT -272 1000 Left 2 !.model BFR92A NPN(IS=0.1213E-15 VAF=30 BF=94.73 IKF=0.46227  XTB=0 BR=10.729 CJC=946.47E-15 CJE=10.416E-15 TR=1.2744E-9 TF=26.796E-12  ITF=0.0044601 VTF=0.32861  XTF=0.3817 RB=14.998
    RC=0.13793 RE=0.29088 Vceo=15 Icrating=4m mfg=Infineon)
    TEXT -904 1024 Left 2 !.tran 0 500n 0

    It's just a two transistor emitter-coupled monostable, but with the two transistors as BFR92's run at 10mA,  it produces 1nsec pulse without fuss.

    Finding the broad-band PNPs to let you translate the output pulse to a
    useful voltage level is tricky. Phil Hobbs has told us that there is a
    least one still in production and available.


    It is a pity it relies on an input pulse shorter than the output - at
    those speeds it would nicer to have a step input somehow?

    piglet

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Bill Sloman@21:1/5 to john larkin on Sat Jun 22 13:13:44 2024
    On 14/06/2024 1:31 am, john larkin wrote:
    On Thu, 13 Jun 2024 16:03:04 +1000, Bill Sloman <bill.sloman@ieee.org>
    wrote:

    On 13/06/2024 4:11 am, john larkin wrote:
    On Wed, 12 Jun 2024 17:22:49 -0000 (UTC), Cursitor Doom
    <cd999666@notformail.com> wrote:

    On Wed, 12 Jun 2024 09:33:17 -0700, john larkin wrote:

    Here's another idea for a fast one-shot. This is the just-apply-money >>>>> version and should get close to 1 ns pulse width and should easily
    trigger at 150 MHz.

    https://www.dropbox.com/scl/fi/1okfo8964bw5m53mjmxs6/
    Pecl_One_Shot_1.jpg?rlkey=dwus6qjyqsynl2rv6uje2xxtj&raw=1

    I can use the other half of the dual comparator elsewhere. This one has >>>>> programmable hysteresis too.

    Exposing my contemptworthy ignorance here no doubt, but what exactly is it >>>> that is fast about this design, John? And what would its application be? >>>
    It would have a leading-edge prop delay of 350 ps, a minimum pulse
    width just over 1 ns, and would easily trigger at 150 MHz. Integrated
    one-shots, xxx123 types, are always terrible, even the obsolete ECL
    ones.

    It would be a programmable delay in a number of possible products,
    including some optical modulators. Just playing right now.

    More dollars could certainly do something faster, but as long as
    customers connect boxes with cables, faster isn't worth a lot. Light
    just moves too slow.

    Any suggestions for a faster one-shot?

    Version 4
    SHEET 1 2924 1040
    WIRE -592 -720 -768 -720
    WIRE 128 -720 -592 -720
    WIRE 304 -720 128 -720
    WIRE 768 -720 304 -720
    WIRE 976 -720 768 -720
    WIRE 1488 -576 1488 -720
    WIRE 128 -560 128 -720
    WIRE 304 -560 304 -720
    WIRE 768 -560 768 -720
    WIRE -592 -384 -592 -720
    WIRE 1072 -368 1072 -400
    WIRE 768 -320 768 -480
    WIRE 960 -320 768 -320
    WIRE 1008 -320 960 -320
    WIRE 128 -288 128 -480
    WIRE 176 -288 128 -288
    WIRE 576 -288 240 -288
    WIRE 768 -208 768 -320
    WIRE 304 -160 304 -480
    WIRE 400 -160 304 -160
    WIRE 576 -160 576 -288
    WIRE 576 -160 480 -160
    WIRE 640 -160 576 -160
    WIRE 704 -160 640 -160
    WIRE -768 -64 -768 -720
    WIRE 128 48 128 -288
    WIRE -272 96 -432 96
    WIRE 64 96 -192 96
    WIRE 640 128 640 -160
    WIRE 304 160 304 -160
    WIRE -432 240 -432 96
    WIRE -768 416 -768 16
    WIRE -768 416 -880 416
    WIRE -736 416 -768 416
    WIRE -592 416 -592 -320
    WIRE -592 416 -736 416
    WIRE -496 416 -592 416
    WIRE -432 416 -432 320
    WIRE -432 416 -496 416
    WIRE 640 416 640 208
    WIRE 640 416 -432 416
    WIRE 1072 416 640 416
    WIRE 128 464 128 144
    WIRE 768 464 768 -112
    WIRE 768 464 128 464
    WIRE -880 496 -880 416
    WIRE 768 496 768 464
    WIRE -736 640 -736 416
    WIRE -496 640 -496 416
    WIRE -736 656 -736 640
    WIRE -736 944 -736 720
    WIRE -496 944 -496 704
    WIRE -496 944 -736 944
    WIRE 304 944 304 240
    WIRE 304 944 -496 944
    WIRE 768 944 768 576
    WIRE 768 944 304 944
    WIRE 1760 944 768 944
    FLAG -880 496 0
    FLAG 960 -320 out
    SYMBOL npn 64 48 R0
    SYMATTR InstName Q1
    SYMATTR Value BFR92A
    SYMBOL npn 704 -208 R0
    SYMATTR InstName Q2
    SYMATTR Value BFR92A
    SYMBOL voltage -768 -80 R0
    WINDOW 123 0 0 Left 0
    WINDOW 39 24 44 Left 2
    SYMATTR SpiceLine Rser=0.1
    SYMATTR InstName V1
    SYMATTR Value 5.0
    SYMBOL voltage -736 624 R0
    WINDOW 123 0 0 Left 0
    WINDOW 39 24 44 Left 2
    SYMATTR SpiceLine Rser=0.1
    SYMATTR InstName V2
    SYMATTR Value 4.5
    SYMBOL voltage -432 224 R0
    WINDOW 123 0 0 Left 0
    WINDOW 39 0 0 Left 0
    SYMATTR InstName V3
    SYMATTR Value PULSE(0 0.2 1n 300p 300p 100p 200n 2)
    SYMBOL res -176 80 R90
    WINDOW 0 0 56 VBottom 2
    WINDOW 3 32 56 VTop 2
    SYMATTR InstName R1
    SYMATTR Value 22
    SYMBOL res 752 480 R0
    SYMATTR InstName R3
    SYMATTR Value 360
    SYMBOL res 112 -576 R0
    SYMATTR InstName R4
    SYMATTR Value 180
    SYMBOL res 624 112 R0
    SYMATTR InstName R5
    SYMATTR Value 43
    SYMBOL res 752 -576 R0
    SYMATTR InstName R6
    SYMATTR Value 180
    SYMBOL res 288 -576 R0
    SYMATTR InstName R2
    SYMATTR Value 1k
    SYMBOL cap 240 -304 R90
    WINDOW 0 0 32 VBottom 2
    WINDOW 3 32 32 VTop 2
    SYMATTR InstName C1
    SYMATTR Value 3.3p
    SYMBOL res 288 144 R0
    SYMATTR InstName R7
    SYMATTR Value 1k2
    SYMBOL res 496 -176 R90
    WINDOW 0 0 56 VBottom 2
    WINDOW 3 32 56 VTop 2
    SYMATTR InstName R13
    SYMATTR Value 43
    SYMBOL cap -608 -384 R0
    SYMATTR InstName C3
    SYMATTR Value 10n
    SYMBOL cap -512 640 R0
    SYMATTR InstName C4
    SYMATTR Value 10n
    TEXT -272 1000 Left 2 !.model BFR92A NPN(IS=0.1213E-15 VAF=30 BF=94.73
    IKF=0.46227 XTB=0 BR=10.729 CJC=946.47E-15 CJE=10.416E-15 TR=1.2744E-9
    TF=26.796E-12 ITF=0.0044601 VTF=0.32861 XTF=0.3817 RB=14.998
    RC=0.13793 RE=0.29088 Vceo=15 Icrating=4m mfg=Infineon)
    TEXT -904 1024 Left 2 !.tran 0 500n 0

    It's just a two transistor emitter-coupled monostable, but with the two
    transistors as BFR92's run at 10mA, it produces 1nsec pulse without fuss. >>
    Finding the broad-band PNPs to let you translate the output pulse to a
    useful voltage level is tricky. Phil Hobbs has told us that there is a
    least one still in production and available.

    What a mess. The output pulse width just follows the input pulse
    width. Unless you change C1, in which case it oscillates.

    Actually, it doesn't. The input pulse has a full-width at half maximum
    of 400psec, and the output pulse width is 1nsec, as intended

    It's ugly too. Obviously frobbed until it seems to work.

    "Ugly" - in this context - seems to mean "not invented by John Larkin".

    It's obviously derived from a simulation I posted earlier, that produced
    a longer output pulse from the same input. The emitter resistor has been
    been made smaller to get a 10mA tail current, and the collector
    resistors scaled down in the same proportion. That narrowed the output pulse,and I tweaked C1 down to 3.3pF to get the 1nsec FWHM output.

    There aren't enough components there to represent a mess, if you have
    any idea what they are doing. If you don't, I supposed that you could
    get it to oscillate. John hasn't posted his simulation, so we don't know
    why it oscillated.

    --
    Bill Sloman, Sydney




    --
    This email has been checked for viruses by Norton antivirus software. www.norton.com

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Bill Sloman@21:1/5 to piglet on Sat Jun 22 13:20:00 2024
    On 15/06/2024 4:02 am, piglet wrote:
    On 13/06/2024 07:03, Bill Sloman wrote:
    On 13/06/2024 4:11 am, john larkin wrote:
    On Wed, 12 Jun 2024 17:22:49 -0000 (UTC), Cursitor Doom
    <cd999666@notformail.com> wrote:

    On Wed, 12 Jun 2024 09:33:17 -0700, john larkin wrote:

    Here's another idea for a fast one-shot. This is the just-apply-money >>>>> version and should get close to 1 ns pulse width and should easily
    trigger at 150 MHz.

    https://www.dropbox.com/scl/fi/1okfo8964bw5m53mjmxs6/
    Pecl_One_Shot_1.jpg?rlkey=dwus6qjyqsynl2rv6uje2xxtj&raw=1

    I can use the other half of the dual comparator elsewhere. This one
    has
    programmable hysteresis too.

    Exposing my contemptworthy ignorance here no doubt, but what exactly
    is it
    that is fast about this design, John? And what would its application
    be?

    It would have a leading-edge prop delay of 350 ps, a minimum pulse
    width just over 1 ns, and would easily trigger at 150 MHz. Integrated
    one-shots, xxx123 types, are always terrible, even the obsolete ECL
    ones.

    It would be a programmable delay in a number of possible products,
    including some optical modulators. Just playing right now.

    More dollars could certainly do something faster, but as long as
    customers connect boxes with cables, faster isn't worth a lot. Light
    just moves too slow.

    Any suggestions for a faster one-shot?

    Version 4
    SHEET 1 2924 1040
    WIRE -592 -720 -768 -720
    WIRE 128 -720 -592 -720
    WIRE 304 -720 128 -720
    WIRE 768 -720 304 -720
    WIRE 976 -720 768 -720
    WIRE 1488 -576 1488 -720
    WIRE 128 -560 128 -720
    WIRE 304 -560 304 -720
    WIRE 768 -560 768 -720
    WIRE -592 -384 -592 -720
    WIRE 1072 -368 1072 -400
    WIRE 768 -320 768 -480
    WIRE 960 -320 768 -320
    WIRE 1008 -320 960 -320
    WIRE 128 -288 128 -480
    WIRE 176 -288 128 -288
    WIRE 576 -288 240 -288
    WIRE 768 -208 768 -320
    WIRE 304 -160 304 -480
    WIRE 400 -160 304 -160
    WIRE 576 -160 576 -288
    WIRE 576 -160 480 -160
    WIRE 640 -160 576 -160
    WIRE 704 -160 640 -160
    WIRE -768 -64 -768 -720
    WIRE 128 48 128 -288
    WIRE -272 96 -432 96
    WIRE 64 96 -192 96
    WIRE 640 128 640 -160
    WIRE 304 160 304 -160
    WIRE -432 240 -432 96
    WIRE -768 416 -768 16
    WIRE -768 416 -880 416
    WIRE -736 416 -768 416
    WIRE -592 416 -592 -320
    WIRE -592 416 -736 416
    WIRE -496 416 -592 416
    WIRE -432 416 -432 320
    WIRE -432 416 -496 416
    WIRE 640 416 640 208
    WIRE 640 416 -432 416
    WIRE 1072 416 640 416
    WIRE 128 464 128 144
    WIRE 768 464 768 -112
    WIRE 768 464 128 464
    WIRE -880 496 -880 416
    WIRE 768 496 768 464
    WIRE -736 640 -736 416
    WIRE -496 640 -496 416
    WIRE -736 656 -736 640
    WIRE -736 944 -736 720
    WIRE -496 944 -496 704
    WIRE -496 944 -736 944
    WIRE 304 944 304 240
    WIRE 304 944 -496 944
    WIRE 768 944 768 576
    WIRE 768 944 304 944
    WIRE 1760 944 768 944
    FLAG -880 496 0
    FLAG 960 -320 out
    SYMBOL npn 64 48 R0
    SYMATTR InstName Q1
    SYMATTR Value BFR92A
    SYMBOL npn 704 -208 R0
    SYMATTR InstName Q2
    SYMATTR Value BFR92A
    SYMBOL voltage -768 -80 R0
    WINDOW 123 0 0 Left 0
    WINDOW 39 24 44 Left 2
    SYMATTR SpiceLine Rser=0.1
    SYMATTR InstName V1
    SYMATTR Value 5.0
    SYMBOL voltage -736 624 R0
    WINDOW 123 0 0 Left 0
    WINDOW 39 24 44 Left 2
    SYMATTR SpiceLine Rser=0.1
    SYMATTR InstName V2
    SYMATTR Value 4.5
    SYMBOL voltage -432 224 R0
    WINDOW 123 0 0 Left 0
    WINDOW 39 0 0 Left 0
    SYMATTR InstName V3
    SYMATTR Value PULSE(0 0.2 1n 300p 300p 100p 200n 2)
    SYMBOL res -176 80 R90
    WINDOW 0 0 56 VBottom 2
    WINDOW 3 32 56 VTop 2
    SYMATTR InstName R1
    SYMATTR Value 22
    SYMBOL res 752 480 R0
    SYMATTR InstName R3
    SYMATTR Value 360
    SYMBOL res 112 -576 R0
    SYMATTR InstName R4
    SYMATTR Value 180
    SYMBOL res 624 112 R0
    SYMATTR InstName R5
    SYMATTR Value 43
    SYMBOL res 752 -576 R0
    SYMATTR InstName R6
    SYMATTR Value 180
    SYMBOL res 288 -576 R0
    SYMATTR InstName R2
    SYMATTR Value 1k
    SYMBOL cap 240 -304 R90
    WINDOW 0 0 32 VBottom 2
    WINDOW 3 32 32 VTop 2
    SYMATTR InstName C1
    SYMATTR Value 3.3p
    SYMBOL res 288 144 R0
    SYMATTR InstName R7
    SYMATTR Value 1k2
    SYMBOL res 496 -176 R90
    WINDOW 0 0 56 VBottom 2
    WINDOW 3 32 56 VTop 2
    SYMATTR InstName R13
    SYMATTR Value 43
    SYMBOL cap -608 -384 R0
    SYMATTR InstName C3
    SYMATTR Value 10n
    SYMBOL cap -512 640 R0
    SYMATTR InstName C4
    SYMATTR Value 10n
    TEXT -272 1000 Left 2 !.model BFR92A NPN(IS=0.1213E-15 VAF=30 BF=94.73
    IKF=0.46227  XTB=0 BR=10.729 CJC=946.47E-15 CJE=10.416E-15
    TR=1.2744E-9 TF=26.796E-12  ITF=0.0044601 VTF=0.32861  XTF=0.3817
    RB=14.998 RC=0.13793 RE=0.29088 Vceo=15 Icrating=4m mfg=Infineon)
    TEXT -904 1024 Left 2 !.tran 0 500n 0

    It's just a two transistor emitter-coupled monostable, but with the
    two transistors as BFR92's run at 10mA,  it produces 1nsec pulse
    without fuss.

    Finding the broad-band PNPs to let you translate the output pulse to a
    useful voltage level is tricky. Phil Hobbs has told us that there is a
    least one still in production and available.


    It is a pity it relies on an input pulse shorter than the output - at
    those speeds it would nicer to have a step input somehow?

    If you have a long input pulse you can use a delay line and an AND gate
    to make a shorter one. That was how I got 0.5nsec +/- 0.05nsec at
    Cambridge Instruments in their 1985 electron beam tester's beam blanking system.

    --
    Bill Sloman, Sydney

    --
    This email has been checked for viruses by Norton antivirus software. www.norton.com

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From john larkin@21:1/5 to All on Fri Jun 21 22:23:30 2024
    On Fri, 14 Jun 2024 19:02:11 +0100, piglet <erichpwagner@hotmail.com>
    wrote:

    On 13/06/2024 07:03, Bill Sloman wrote:
    On 13/06/2024 4:11 am, john larkin wrote:
    On Wed, 12 Jun 2024 17:22:49 -0000 (UTC), Cursitor Doom
    <cd999666@notformail.com> wrote:

    On Wed, 12 Jun 2024 09:33:17 -0700, john larkin wrote:

    Here's another idea for a fast one-shot. This is the just-apply-money >>>>> version and should get close to 1 ns pulse width and should easily
    trigger at 150 MHz.

    https://www.dropbox.com/scl/fi/1okfo8964bw5m53mjmxs6/
    Pecl_One_Shot_1.jpg?rlkey=dwus6qjyqsynl2rv6uje2xxtj&raw=1

    I can use the other half of the dual comparator elsewhere. This one has >>>>> programmable hysteresis too.

    Exposing my contemptworthy ignorance here no doubt, but what exactly
    is it
    that is fast about this design, John? And what would its application be? >>>
    It would have a leading-edge prop delay of 350 ps, a minimum pulse
    width just over 1 ns, and would easily trigger at 150 MHz. Integrated
    one-shots, xxx123 types, are always terrible, even the obsolete ECL
    ones.

    It would be a programmable delay in a number of possible products,
    including some optical modulators. Just playing right now.

    More dollars could certainly do something faster, but as long as
    customers connect boxes with cables, faster isn't worth a lot. Light
    just moves too slow.

    Any suggestions for a faster one-shot?

    Version 4
    SHEET 1 2924 1040
    WIRE -592 -720 -768 -720
    WIRE 128 -720 -592 -720
    WIRE 304 -720 128 -720
    WIRE 768 -720 304 -720
    WIRE 976 -720 768 -720
    WIRE 1488 -576 1488 -720
    WIRE 128 -560 128 -720
    WIRE 304 -560 304 -720
    WIRE 768 -560 768 -720
    WIRE -592 -384 -592 -720
    WIRE 1072 -368 1072 -400
    WIRE 768 -320 768 -480
    WIRE 960 -320 768 -320
    WIRE 1008 -320 960 -320
    WIRE 128 -288 128 -480
    WIRE 176 -288 128 -288
    WIRE 576 -288 240 -288
    WIRE 768 -208 768 -320
    WIRE 304 -160 304 -480
    WIRE 400 -160 304 -160
    WIRE 576 -160 576 -288
    WIRE 576 -160 480 -160
    WIRE 640 -160 576 -160
    WIRE 704 -160 640 -160
    WIRE -768 -64 -768 -720
    WIRE 128 48 128 -288
    WIRE -272 96 -432 96
    WIRE 64 96 -192 96
    WIRE 640 128 640 -160
    WIRE 304 160 304 -160
    WIRE -432 240 -432 96
    WIRE -768 416 -768 16
    WIRE -768 416 -880 416
    WIRE -736 416 -768 416
    WIRE -592 416 -592 -320
    WIRE -592 416 -736 416
    WIRE -496 416 -592 416
    WIRE -432 416 -432 320
    WIRE -432 416 -496 416
    WIRE 640 416 640 208
    WIRE 640 416 -432 416
    WIRE 1072 416 640 416
    WIRE 128 464 128 144
    WIRE 768 464 768 -112
    WIRE 768 464 128 464
    WIRE -880 496 -880 416
    WIRE 768 496 768 464
    WIRE -736 640 -736 416
    WIRE -496 640 -496 416
    WIRE -736 656 -736 640
    WIRE -736 944 -736 720
    WIRE -496 944 -496 704
    WIRE -496 944 -736 944
    WIRE 304 944 304 240
    WIRE 304 944 -496 944
    WIRE 768 944 768 576
    WIRE 768 944 304 944
    WIRE 1760 944 768 944
    FLAG -880 496 0
    FLAG 960 -320 out
    SYMBOL npn 64 48 R0
    SYMATTR InstName Q1
    SYMATTR Value BFR92A
    SYMBOL npn 704 -208 R0
    SYMATTR InstName Q2
    SYMATTR Value BFR92A
    SYMBOL voltage -768 -80 R0
    WINDOW 123 0 0 Left 0
    WINDOW 39 24 44 Left 2
    SYMATTR SpiceLine Rser=0.1
    SYMATTR InstName V1
    SYMATTR Value 5.0
    SYMBOL voltage -736 624 R0
    WINDOW 123 0 0 Left 0
    WINDOW 39 24 44 Left 2
    SYMATTR SpiceLine Rser=0.1
    SYMATTR InstName V2
    SYMATTR Value 4.5
    SYMBOL voltage -432 224 R0
    WINDOW 123 0 0 Left 0
    WINDOW 39 0 0 Left 0
    SYMATTR InstName V3
    SYMATTR Value PULSE(0 0.2 1n 300p 300p 100p 200n 2)
    SYMBOL res -176 80 R90
    WINDOW 0 0 56 VBottom 2
    WINDOW 3 32 56 VTop 2
    SYMATTR InstName R1
    SYMATTR Value 22
    SYMBOL res 752 480 R0
    SYMATTR InstName R3
    SYMATTR Value 360
    SYMBOL res 112 -576 R0
    SYMATTR InstName R4
    SYMATTR Value 180
    SYMBOL res 624 112 R0
    SYMATTR InstName R5
    SYMATTR Value 43
    SYMBOL res 752 -576 R0
    SYMATTR InstName R6
    SYMATTR Value 180
    SYMBOL res 288 -576 R0
    SYMATTR InstName R2
    SYMATTR Value 1k
    SYMBOL cap 240 -304 R90
    WINDOW 0 0 32 VBottom 2
    WINDOW 3 32 32 VTop 2
    SYMATTR InstName C1
    SYMATTR Value 3.3p
    SYMBOL res 288 144 R0
    SYMATTR InstName R7
    SYMATTR Value 1k2
    SYMBOL res 496 -176 R90
    WINDOW 0 0 56 VBottom 2
    WINDOW 3 32 56 VTop 2
    SYMATTR InstName R13
    SYMATTR Value 43
    SYMBOL cap -608 -384 R0
    SYMATTR InstName C3
    SYMATTR Value 10n
    SYMBOL cap -512 640 R0
    SYMATTR InstName C4
    SYMATTR Value 10n
    TEXT -272 1000 Left 2 !.model BFR92A NPN(IS=0.1213E-15 VAF=30 BF=94.73
    IKF=0.46227  XTB=0 BR=10.729 CJC=946.47E-15 CJE=10.416E-15 TR=1.2744E-9
    TF=26.796E-12  ITF=0.0044601 VTF=0.32861  XTF=0.3817 RB=14.998
    RC=0.13793 RE=0.29088 Vceo=15 Icrating=4m mfg=Infineon)
    TEXT -904 1024 Left 2 !.tran 0 500n 0

    It's just a two transistor emitter-coupled monostable, but with the two
    transistors as BFR92's run at 10mA,  it produces 1nsec pulse without fuss. >>
    Finding the broad-band PNPs to let you translate the output pulse to a
    useful voltage level is tricky. Phil Hobbs has told us that there is a
    least one still in production and available.


    It is a pity it relies on an input pulse shorter than the output - at
    those speeds it would nicer to have a step input somehow?

    piglet

    It's really a slow diffamp, not a one-shot. It will make a nice clean
    1 second output, given a 1 second trigger input.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From john larkin@21:1/5 to All on Fri Jun 21 22:20:31 2024
    On Sat, 22 Jun 2024 13:13:44 +1000, Bill Sloman <bill.sloman@ieee.org>
    wrote:

    On 14/06/2024 1:31 am, john larkin wrote:
    On Thu, 13 Jun 2024 16:03:04 +1000, Bill Sloman <bill.sloman@ieee.org>
    wrote:

    On 13/06/2024 4:11 am, john larkin wrote:
    On Wed, 12 Jun 2024 17:22:49 -0000 (UTC), Cursitor Doom
    <cd999666@notformail.com> wrote:

    On Wed, 12 Jun 2024 09:33:17 -0700, john larkin wrote:

    Here's another idea for a fast one-shot. This is the just-apply-money >>>>>> version and should get close to 1 ns pulse width and should easily >>>>>> trigger at 150 MHz.

    https://www.dropbox.com/scl/fi/1okfo8964bw5m53mjmxs6/
    Pecl_One_Shot_1.jpg?rlkey=dwus6qjyqsynl2rv6uje2xxtj&raw=1

    I can use the other half of the dual comparator elsewhere. This one has >>>>>> programmable hysteresis too.

    Exposing my contemptworthy ignorance here no doubt, but what exactly is it
    that is fast about this design, John? And what would its application be? >>>>
    It would have a leading-edge prop delay of 350 ps, a minimum pulse
    width just over 1 ns, and would easily trigger at 150 MHz. Integrated
    one-shots, xxx123 types, are always terrible, even the obsolete ECL
    ones.

    It would be a programmable delay in a number of possible products,
    including some optical modulators. Just playing right now.

    More dollars could certainly do something faster, but as long as
    customers connect boxes with cables, faster isn't worth a lot. Light
    just moves too slow.

    Any suggestions for a faster one-shot?

    Version 4
    SHEET 1 2924 1040
    WIRE -592 -720 -768 -720
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    SYMATTR InstName Q1
    SYMATTR Value BFR92A
    SYMBOL npn 704 -208 R0
    SYMATTR InstName Q2
    SYMATTR Value BFR92A
    SYMBOL voltage -768 -80 R0
    WINDOW 123 0 0 Left 0
    WINDOW 39 24 44 Left 2
    SYMATTR SpiceLine Rser=0.1
    SYMATTR InstName V1
    SYMATTR Value 5.0
    SYMBOL voltage -736 624 R0
    WINDOW 123 0 0 Left 0
    WINDOW 39 24 44 Left 2
    SYMATTR SpiceLine Rser=0.1
    SYMATTR InstName V2
    SYMATTR Value 4.5
    SYMBOL voltage -432 224 R0
    WINDOW 123 0 0 Left 0
    WINDOW 39 0 0 Left 0
    SYMATTR InstName V3
    SYMATTR Value PULSE(0 0.2 1n 300p 300p 100p 200n 2)
    SYMBOL res -176 80 R90
    WINDOW 0 0 56 VBottom 2
    WINDOW 3 32 56 VTop 2
    SYMATTR InstName R1
    SYMATTR Value 22
    SYMBOL res 752 480 R0
    SYMATTR InstName R3
    SYMATTR Value 360
    SYMBOL res 112 -576 R0
    SYMATTR InstName R4
    SYMATTR Value 180
    SYMBOL res 624 112 R0
    SYMATTR InstName R5
    SYMATTR Value 43
    SYMBOL res 752 -576 R0
    SYMATTR InstName R6
    SYMATTR Value 180
    SYMBOL res 288 -576 R0
    SYMATTR InstName R2
    SYMATTR Value 1k
    SYMBOL cap 240 -304 R90
    WINDOW 0 0 32 VBottom 2
    WINDOW 3 32 32 VTop 2
    SYMATTR InstName C1
    SYMATTR Value 3.3p
    SYMBOL res 288 144 R0
    SYMATTR InstName R7
    SYMATTR Value 1k2
    SYMBOL res 496 -176 R90
    WINDOW 0 0 56 VBottom 2
    WINDOW 3 32 56 VTop 2
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    SYMATTR Value 43
    SYMBOL cap -608 -384 R0
    SYMATTR InstName C3
    SYMATTR Value 10n
    SYMBOL cap -512 640 R0
    SYMATTR InstName C4
    SYMATTR Value 10n
    TEXT -272 1000 Left 2 !.model BFR92A NPN(IS=0.1213E-15 VAF=30 BF=94.73
    IKF=0.46227 XTB=0 BR=10.729 CJC=946.47E-15 CJE=10.416E-15 TR=1.2744E-9
    TF=26.796E-12 ITF=0.0044601 VTF=0.32861 XTF=0.3817 RB=14.998
    RC=0.13793 RE=0.29088 Vceo=15 Icrating=4m mfg=Infineon)
    TEXT -904 1024 Left 2 !.tran 0 500n 0

    It's just a two transistor emitter-coupled monostable, but with the two
    transistors as BFR92's run at 10mA, it produces 1nsec pulse without fuss. >>>
    Finding the broad-band PNPs to let you translate the output pulse to a
    useful voltage level is tricky. Phil Hobbs has told us that there is a
    least one still in production and available.

    What a mess. The output pulse width just follows the input pulse
    width. Unless you change C1, in which case it oscillates.

    Actually, it doesn't. The input pulse has a full-width at half maximum
    of 400psec, and the output pulse width is 1nsec, as intended

    It's not a one-shot, it's a diffamp. Put in a 50 ns trigger and it
    will make a 50 ns output.

    And it makes the common beginner error of assuming that two
    transistors are absolutely identical, and at the same temperature,
    because Spice does that.

    The critical 40 mV of diff offeset is derived by the diference between
    the tweaked power supplies and, I suppose, two 1% resistors. That is
    really weird. And unsafe.

    The dangling wire scraps could roll around and short things.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Bill Sloman@21:1/5 to john larkin on Sat Jun 22 17:01:16 2024
    On 22/06/2024 3:20 pm, john larkin wrote:
    On Sat, 22 Jun 2024 13:13:44 +1000, Bill Sloman <bill.sloman@ieee.org>
    wrote:

    On 14/06/2024 1:31 am, john larkin wrote:
    On Thu, 13 Jun 2024 16:03:04 +1000, Bill Sloman <bill.sloman@ieee.org>
    wrote:

    On 13/06/2024 4:11 am, john larkin wrote:
    On Wed, 12 Jun 2024 17:22:49 -0000 (UTC), Cursitor Doom
    <cd999666@notformail.com> wrote:

    On Wed, 12 Jun 2024 09:33:17 -0700, john larkin wrote:

    Here's another idea for a fast one-shot. This is the just-apply-money >>>>>>> version and should get close to 1 ns pulse width and should easily >>>>>>> trigger at 150 MHz.

    https://www.dropbox.com/scl/fi/1okfo8964bw5m53mjmxs6/
    Pecl_One_Shot_1.jpg?rlkey=dwus6qjyqsynl2rv6uje2xxtj&raw=1

    I can use the other half of the dual comparator elsewhere. This one has >>>>>>> programmable hysteresis too.

    Exposing my contemptworthy ignorance here no doubt, but what exactly is it
    that is fast about this design, John? And what would its application be? >>>>>
    It would have a leading-edge prop delay of 350 ps, a minimum pulse
    width just over 1 ns, and would easily trigger at 150 MHz. Integrated >>>>> one-shots, xxx123 types, are always terrible, even the obsolete ECL
    ones.

    It would be a programmable delay in a number of possible products,
    including some optical modulators. Just playing right now.

    More dollars could certainly do something faster, but as long as
    customers connect boxes with cables, faster isn't worth a lot. Light >>>>> just moves too slow.

    Any suggestions for a faster one-shot?

    Version 4
    SHEET 1 2924 1040
    WIRE -592 -720 -768 -720
    WIRE 128 -720 -592 -720
    WIRE 304 -720 128 -720
    WIRE 768 -720 304 -720
    WIRE 976 -720 768 -720
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    WIRE 128 -560 128 -720
    WIRE 304 -560 304 -720
    WIRE 768 -560 768 -720
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    WIRE 1072 -368 1072 -400
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    SYMBOL npn 64 48 R0
    SYMATTR InstName Q1
    SYMATTR Value BFR92A
    SYMBOL npn 704 -208 R0
    SYMATTR InstName Q2
    SYMATTR Value BFR92A
    SYMBOL voltage -768 -80 R0
    WINDOW 123 0 0 Left 0
    WINDOW 39 24 44 Left 2
    SYMATTR SpiceLine Rser=0.1
    SYMATTR InstName V1
    SYMATTR Value 5.0
    SYMBOL voltage -736 624 R0
    WINDOW 123 0 0 Left 0
    WINDOW 39 24 44 Left 2
    SYMATTR SpiceLine Rser=0.1
    SYMATTR InstName V2
    SYMATTR Value 4.5
    SYMBOL voltage -432 224 R0
    WINDOW 123 0 0 Left 0
    WINDOW 39 0 0 Left 0
    SYMATTR InstName V3
    SYMATTR Value PULSE(0 0.2 1n 300p 300p 100p 200n 2)
    SYMBOL res -176 80 R90
    WINDOW 0 0 56 VBottom 2
    WINDOW 3 32 56 VTop 2
    SYMATTR InstName R1
    SYMATTR Value 22
    SYMBOL res 752 480 R0
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    SYMATTR Value 360
    SYMBOL res 112 -576 R0
    SYMATTR InstName R4
    SYMATTR Value 180
    SYMBOL res 624 112 R0
    SYMATTR InstName R5
    SYMATTR Value 43
    SYMBOL res 752 -576 R0
    SYMATTR InstName R6
    SYMATTR Value 180
    SYMBOL res 288 -576 R0
    SYMATTR InstName R2
    SYMATTR Value 1k
    SYMBOL cap 240 -304 R90
    WINDOW 0 0 32 VBottom 2
    WINDOW 3 32 32 VTop 2
    SYMATTR InstName C1
    SYMATTR Value 3.3p
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    SYMATTR Value 1k2
    SYMBOL res 496 -176 R90
    WINDOW 0 0 56 VBottom 2
    WINDOW 3 32 56 VTop 2
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    SYMATTR Value 43
    SYMBOL cap -608 -384 R0
    SYMATTR InstName C3
    SYMATTR Value 10n
    SYMBOL cap -512 640 R0
    SYMATTR InstName C4
    SYMATTR Value 10n
    TEXT -272 1000 Left 2 !.model BFR92A NPN(IS=0.1213E-15 VAF=30 BF=94.73 >>>> IKF=0.46227 XTB=0 BR=10.729 CJC=946.47E-15 CJE=10.416E-15 TR=1.2744E-9 >>>> TF=26.796E-12 ITF=0.0044601 VTF=0.32861 XTF=0.3817 RB=14.998
    RC=0.13793 RE=0.29088 Vceo=15 Icrating=4m mfg=Infineon)
    TEXT -904 1024 Left 2 !.tran 0 500n 0

    It's just a two transistor emitter-coupled monostable, but with the two >>>> transistors as BFR92's run at 10mA, it produces 1nsec pulse without fuss. >>>>
    Finding the broad-band PNPs to let you translate the output pulse to a >>>> useful voltage level is tricky. Phil Hobbs has told us that there is a >>>> least one still in production and available.

    What a mess. The output pulse width just follows the input pulse
    width. Unless you change C1, in which case it oscillates.

    Actually, it doesn't. The input pulse has a full-width at half maximum
    of 400psec, and the output pulse width is 1nsec, as intended

    It's not a one-shot, it's a diffamp. Put in a 50 ns trigger and it
    will make a 50 ns output.

    Not that you have posted a sim that illustrates this.

    And it makes the common beginner error of assuming that two
    transistors are absolutely identical, and at the same temperature,
    because Spice does that.

    The critical 40 mV of diff offeset is derived by the difference between
    the tweaked power supplies and, I suppose, two 1% resistors. That is
    really weird. And unsafe.

    It may not make any sense to you.

    R2 and R7 deliver about about 0.8ma of bias current into the divider R13
    + R5. which normally biases Q2 on - with about 8.5mA of emitter current.
    Q1 carries 1.5mA of emitter current.

    You don't have to increase the base voltage of Q1 much to bias the pair
    into an unstable state, in which the emitter current of Q1 rises to 10mA
    then decays back to 1.5mA.

    The excursion into instability is what produces the output pulse.
    The dangling wire scraps could roll around and short things.

    Not inside a sim. In real life this sort of circuit is always made as a
    printed circuit board with traces running over ground plane - or at
    least I've never done it any other way.

    --
    Bill Sloman, Sydney




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  • From Bill Sloman@21:1/5 to john larkin on Sun Jun 23 11:38:28 2024
    On 22/06/2024 3:23 pm, john larkin wrote:
    On Fri, 14 Jun 2024 19:02:11 +0100, piglet <erichpwagner@hotmail.com>
    wrote:

    On 13/06/2024 07:03, Bill Sloman wrote:
    On 13/06/2024 4:11 am, john larkin wrote:
    On Wed, 12 Jun 2024 17:22:49 -0000 (UTC), Cursitor Doom
    <cd999666@notformail.com> wrote:

    On Wed, 12 Jun 2024 09:33:17 -0700, john larkin wrote:


    <snip>

    It's really a slow diffamp, not a one-shot. It will make a nice clean
    1 second output, given a 1 second trigger input.

    It isn't. John could have tried to simulate his "one second trigger
    input", if he could have worked out what he meant by that.

    And it is hard to make a really slow differential amplifier out of a
    BFR92 long-tailed pair.

    He got very excited about the 43mV threshold voltage. Just for fun, I
    increased R7 in my simulation from 1k2 to 1k5, which doubles the threshold.

    The same trigger pulse gave a visually identical output pulse. My guess
    is that it will be picoseconds later and picoseconds narrower, but I'm
    not going to make a meal of it by actually measuring the differences.

    --
    Bill Sloman, Sydney


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  • From Cursitor Doom@21:1/5 to Bill Sloman on Sun Jun 23 17:01:45 2024
    On Sun, 23 Jun 2024 11:38:28 +1000, Bill Sloman wrote:

    On 22/06/2024 3:23 pm, john larkin wrote:
    On Fri, 14 Jun 2024 19:02:11 +0100, piglet <erichpwagner@hotmail.com>
    wrote:

    On 13/06/2024 07:03, Bill Sloman wrote:
    On 13/06/2024 4:11 am, john larkin wrote:
    On Wed, 12 Jun 2024 17:22:49 -0000 (UTC), Cursitor Doom
    <cd999666@notformail.com> wrote:

    On Wed, 12 Jun 2024 09:33:17 -0700, john larkin wrote:


    <snip>

    It's really a slow diffamp, not a one-shot. It will make a nice clean 1
    second output, given a 1 second trigger input.

    It isn't. John could have tried to simulate his "one second trigger
    input", if he could have worked out what he meant by that.

    And it is hard to make a really slow differential amplifier out of a
    BFR92 long-tailed pair.

    He got very excited about the 43mV threshold voltage. Just for fun, I increased R7 in my simulation from 1k2 to 1k5, which doubles the
    threshold.

    The same trigger pulse gave a visually identical output pulse. My guess
    is that it will be picoseconds later and picoseconds narrower, but I'm
    not going to make a meal of it by actually measuring the differences.

    --
    Bill Sloman, Sydney

    When I needed a design for a fast pulse generator, Jim Thompson very
    kindly came up with the goods for me and was happy to do it for free. Jim designed quite a lot of bits and pieces for me over the years. He was a *genuine* contributor in the true spirit of mutual assistance that the
    'net used to be all about. You could learn a thing or two from Jim's
    exemplary conduct here, Bill. Stop being a condescending wanker and chip-
    in something useful for a change.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From john larkin@21:1/5 to cd999666@notformail.com on Sun Jun 23 10:36:35 2024
    On Sun, 23 Jun 2024 17:01:45 -0000 (UTC), Cursitor Doom <cd999666@notformail.com> wrote:

    On Sun, 23 Jun 2024 11:38:28 +1000, Bill Sloman wrote:

    On 22/06/2024 3:23 pm, john larkin wrote:
    On Fri, 14 Jun 2024 19:02:11 +0100, piglet <erichpwagner@hotmail.com>
    wrote:

    On 13/06/2024 07:03, Bill Sloman wrote:
    On 13/06/2024 4:11 am, john larkin wrote:
    On Wed, 12 Jun 2024 17:22:49 -0000 (UTC), Cursitor Doom
    <cd999666@notformail.com> wrote:

    On Wed, 12 Jun 2024 09:33:17 -0700, john larkin wrote:


    <snip>

    It's really a slow diffamp, not a one-shot. It will make a nice clean 1
    second output, given a 1 second trigger input.

    It isn't. John could have tried to simulate his "one second trigger
    input", if he could have worked out what he meant by that.

    And it is hard to make a really slow differential amplifier out of a
    BFR92 long-tailed pair.

    He got very excited about the 43mV threshold voltage. Just for fun, I
    increased R7 in my simulation from 1k2 to 1k5, which doubles the
    threshold.

    The same trigger pulse gave a visually identical output pulse. My guess
    is that it will be picoseconds later and picoseconds narrower, but I'm
    not going to make a meal of it by actually measuring the differences.

    --
    Bill Sloman, Sydney

    When I needed a design for a fast pulse generator, Jim Thompson very
    kindly came up with the goods for me and was happy to do it for free. Jim >designed quite a lot of bits and pieces for me over the years. He was a >*genuine* contributor in the true spirit of mutual assistance that the
    'net used to be all about. You could learn a thing or two from Jim's >exemplary conduct here, Bill. Stop being a condescending wanker and chip-
    in something useful for a change.

    There are some screamong fast CMOS gates and flops around that cost
    pennies.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Bill Sloman@21:1/5 to Cursitor Doom on Mon Jun 24 12:10:10 2024
    On 24/06/2024 3:01 am, Cursitor Doom wrote:
    On Sun, 23 Jun 2024 11:38:28 +1000, Bill Sloman wrote:

    On 22/06/2024 3:23 pm, john larkin wrote:
    On Fri, 14 Jun 2024 19:02:11 +0100, piglet <erichpwagner@hotmail.com>
    wrote:

    On 13/06/2024 07:03, Bill Sloman wrote:
    On 13/06/2024 4:11 am, john larkin wrote:
    On Wed, 12 Jun 2024 17:22:49 -0000 (UTC), Cursitor Doom
    <cd999666@notformail.com> wrote:

    On Wed, 12 Jun 2024 09:33:17 -0700, john larkin wrote:


    <snip>

    It's really a slow diffamp, not a one-shot. It will make a nice clean 1
    second output, given a 1 second trigger input.

    It isn't. John could have tried to simulate his "one second trigger
    input", if he could have worked out what he meant by that.

    And it is hard to make a really slow differential amplifier out of a
    BFR92 long-tailed pair.

    He got very excited about the 43mV threshold voltage. Just for fun, I
    increased R7 in my simulation from 1k2 to 1k5, which doubles the
    threshold.

    The same trigger pulse gave a visually identical output pulse. My guess
    is that it will be picoseconds later and picoseconds narrower, but I'm
    not going to make a meal of it by actually measuring the differences.

    When I needed a design for a fast pulse generator, Jim Thompson very
    kindly came up with the goods for me and was happy to do it for free.

    Pointed you at the right application note? Most of the work in doing
    that is finding out what you actually wanted to do.

    Jim designed quite a lot of bits and pieces for me over the years. He was a *genuine* contributor in the true spirit of mutual assistance that the
    'net used to be all about.

    He was a contract integrated circuit designer, and got paid for anything serious. At one point he claimed that he had denounced me to the FBI for
    being "dangerously anti-American". That "true spirit of mutual
    assistance" came with a certain amount of unpleasant baggage.

    You could learn a thing or two from Jim's exemplary conduct here, Bill. Stop being a condescending wanker and chip-
    in something useful for a change.

    Just like you do?

    --
    Bill Sloman, Sydney

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  • From Bill Sloman@21:1/5 to john larkin on Mon Jun 24 12:34:58 2024
    On 24/06/2024 3:36 am, john larkin wrote:
    On Sun, 23 Jun 2024 17:01:45 -0000 (UTC), Cursitor Doom <cd999666@notformail.com> wrote:

    On Sun, 23 Jun 2024 11:38:28 +1000, Bill Sloman wrote:

    On 22/06/2024 3:23 pm, john larkin wrote:
    On Fri, 14 Jun 2024 19:02:11 +0100, piglet <erichpwagner@hotmail.com>
    wrote:

    On 13/06/2024 07:03, Bill Sloman wrote:
    On 13/06/2024 4:11 am, john larkin wrote:
    On Wed, 12 Jun 2024 17:22:49 -0000 (UTC), Cursitor Doom
    <cd999666@notformail.com> wrote:

    On Wed, 12 Jun 2024 09:33:17 -0700, john larkin wrote:

    <snip>

    There are some screamingly fast CMOS gates and flops around that cost pennies.

    And there have been for years. You started this thread with a pencil
    sketch that included an 10EP51 ($6.53) and an ADCMP562 ($3.15).

    Two BFR92 ($0.64 each)and couple of resistors and capacitors can do the
    same job, if you know what you are doing.

    You pencil sketch didn't tell us much about what you were trying to do,
    or why, and nothing much about the input - "Trig In" as a balanced PECL
    signal tells us about the signal levels, but nothing else.

    As an effort to look like a circuit designer, it wasn't impressive.

    --
    Bill Sloman, Sydney


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