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  • Re: trying to make an audio loopback/antenna cable for FM recording

    From Charles Lucas@21:1/5 to Bodger on Wed Jan 18 09:15:36 2023
    On Saturday, January 14, 2023 at 5:29:13 PM UTC-6, Bodger wrote:
    On 1/14/2023 4:25 PM, Bob F wrote:
    On 1/14/2023 1:03 PM, Bodger wrote:
    On 1/14/2023 2:17 PM, Bob F wrote:
    I have been trying to get my Galaxy S9 to record FM radio programs.
    NextRadio is the only app that I have gotten to work to receive FM using >>> the internal tuner, but it has no record capability.
    snip...

    I have no idea about your problem but I'm gobsmacked that a phone has an >> external microphone input. I've never seen or heard of such a thing.


    It is the same jack that you plug headphones into. Completely compatible with headphones that include a mic with a 4 conductor TRRS plug. I think that is pretty common.

    I should add to the original post that my OS is updated to Android 10, G960UTUES9FVD1.
    OK, now that makes sense. Somehow my mind jumped to the image of a separate microphone input. Probably some gray cells are winking out from lack of use...

    A signal always travels from its output to its input as long as the rules of proper
    power and impedance are followed along the way- kind of like a glorified postal system, from a conceptual sense.

    The headphone jack can be use as a variable audio output jack when using a patch
    cord or Y-adapter patch cable from that device to an RCA audio R/L audio input on
    an analog recording device (converting the impedance from an 1/8" (3.5 mm) jack at 32 ohms to an RCA jack at 1000 ohms) which leads up to an analog device.

    Or you can use an 1/8" male to male patch cable to go to a computer line input or
    other similar device to convert the signal to a digital sampler (starting out as analog
    and then getting converted to a digital media in the processing). You have to remember
    level control is also very important. Don't overload the headphone outs with "too much"
    signal (or distortive audio) or avoid overdriving the signal.

    Good Luck.

    Charles Lucas

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Charles Lucas@21:1/5 to Bob F on Mon Jan 23 09:35:41 2023
    On Friday, January 20, 2023 at 10:51:04 PM UTC-6, Bob F wrote:
    On 1/18/2023 9:15 AM, Charles Lucas wrote:
    On Saturday, January 14, 2023 at 5:29:13 PM UTC-6, Bodger wrote:
    On 1/14/2023 4:25 PM, Bob F wrote:
    On 1/14/2023 1:03 PM, Bodger wrote:
    On 1/14/2023 2:17 PM, Bob F wrote:
    I have been trying to get my Galaxy S9 to record FM radio programs. >>>>> NextRadio is the only app that I have gotten to work to receive FM using
    the internal tuner, but it has no record capability.
    snip...

    I have no idea about your problem but I'm gobsmacked that a phone has an >>>> external microphone input. I've never seen or heard of such a thing. >>>>

    It is the same jack that you plug headphones into. Completely compatible >>> with headphones that include a mic with a 4 conductor TRRS plug. I think >>> that is pretty common.

    I should add to the original post that my OS is updated to Android 10, >>> G960UTUES9FVD1.
    OK, now that makes sense. Somehow my mind jumped to the image of a separate
    microphone input. Probably some gray cells are winking out from lack of use...

    A signal always travels from its output to its input as long as the rules of proper
    power and impedance are followed along the way- kind of like a glorified postal
    system, from a conceptual sense.

    The headphone jack can be use as a variable audio output jack when using a patch
    cord or Y-adapter patch cable from that device to an RCA audio R/L audio input on
    an analog recording device (converting the impedance from an 1/8" (3.5 mm) jack
    at 32 ohms to an RCA jack at 1000 ohms) which leads up to an analog device.

    Or you can use an 1/8" male to male patch cable to go to a computer line input or
    other similar device to convert the signal to a digital sampler (starting out as analog
    and then getting converted to a digital media in the processing). You have to remember
    level control is also very important. Don't overload the headphone outs with "too much"
    signal (or distortive audio) or avoid overdriving the signal.

    I tried a half dozen recording apps to try to record the NextRadio audio
    from the headphone jack back at a lower level into the mic input. One of
    them "Voice recorder" 21.3.55.16, causes NextRadio to stop receiving/outputting the FM audio while it is recording.

    The other recording apps I tried would let NextRadio keep going, but the
    app shows zero signal, so no audio gets recorded.

    I tried a couple of the apps while playing an mp3 file on the phone, and
    the audio was recorded properly.

    So, it really seems like NextRadio is doing something wierd to prevent recording of it's output.

    Can anyone propose what they might be doing, or ways to get past it.

    I cannot find any other FM apps that will run on my S9.

    I repeated this message for the benefit of all concerned.

    We never addressed the software you use. Some software is not licensed to pickup signals
    for recording because they want you to pay money for that. You can download several
    free audio recording or dubbing software apps, record in .mp3 at the desired rate, and
    then copy and paste the completed file over to NextRadio's output folder for audio so
    you can play it back.

    Or you can record it in 16 bit Stereo wave format (.wav) file, convert it to .mp3 format
    you desire to convert it to with a convertor. Then dump the file into NextRadio's
    output folder to playback the finished .mp3 file. In this way, you can bypass the
    software you speak of stringent requirements and pedantic quirks.

    FYI, sometimes, there is a DRM (Digital Rights Management) on these files or software
    that play them to prohibit copying copywritten files. DRM is a form of a "copy" guard,
    again because it boils down to the fact that they want you to pay money to get the
    composite signal that comes from them. I just provided you work arounds without the cost and the hassle; I also warn that this post is for educational purposes only
    regarding recording and conversion of signal and is not an encouragement to violate
    any copyright or infringe upon anyone's work in any other form otherwise.

    Good luck,

    Charles Lucas

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Bob F@21:1/5 to Charles Lucas on Mon Jan 23 20:09:18 2023
    On 1/23/2023 9:35 AM, Charles Lucas wrote:
    On Friday, January 20, 2023 at 10:51:04 PM UTC-6, Bob F wrote:
    On 1/18/2023 9:15 AM, Charles Lucas wrote:
    On Saturday, January 14, 2023 at 5:29:13 PM UTC-6, Bodger wrote:
    On 1/14/2023 4:25 PM, Bob F wrote:
    On 1/14/2023 1:03 PM, Bodger wrote:
    On 1/14/2023 2:17 PM, Bob F wrote:
    I have been trying to get my Galaxy S9 to record FM radio programs. >>>>>>> NextRadio is the only app that I have gotten to work to receive FM using
    the internal tuner, but it has no record capability.
    snip...

    I have no idea about your problem but I'm gobsmacked that a phone has an >>>>>> external microphone input. I've never seen or heard of such a thing. >>>>>>

    It is the same jack that you plug headphones into. Completely compatible >>>>> with headphones that include a mic with a 4 conductor TRRS plug. I think >>>>> that is pretty common.

    I should add to the original post that my OS is updated to Android 10, >>>>> G960UTUES9FVD1.
    OK, now that makes sense. Somehow my mind jumped to the image of a separate
    microphone input. Probably some gray cells are winking out from lack of use...

    A signal always travels from its output to its input as long as the rules of proper
    power and impedance are followed along the way- kind of like a glorified postal
    system, from a conceptual sense.

    The headphone jack can be use as a variable audio output jack when using a patch
    cord or Y-adapter patch cable from that device to an RCA audio R/L audio input on
    an analog recording device (converting the impedance from an 1/8" (3.5 mm) jack
    at 32 ohms to an RCA jack at 1000 ohms) which leads up to an analog device. >>>
    Or you can use an 1/8" male to male patch cable to go to a computer line input or
    other similar device to convert the signal to a digital sampler (starting out as analog
    and then getting converted to a digital media in the processing). You have to remember
    level control is also very important. Don't overload the headphone outs with "too much"
    signal (or distortive audio) or avoid overdriving the signal.

    I tried a half dozen recording apps to try to record the NextRadio audio
    from the headphone jack back at a lower level into the mic input. One of
    them "Voice recorder" 21.3.55.16, causes NextRadio to stop
    receiving/outputting the FM audio while it is recording.

    The other recording apps I tried would let NextRadio keep going, but the
    app shows zero signal, so no audio gets recorded.

    I tried a couple of the apps while playing an mp3 file on the phone, and
    the audio was recorded properly.

    So, it really seems like NextRadio is doing something wierd to prevent
    recording of it's output.

    Can anyone propose what they might be doing, or ways to get past it.

    I cannot find any other FM apps that will run on my S9.

    I repeated this message for the benefit of all concerned.

    We never addressed the software you use. Some software is not licensed to pickup signals
    for recording because they want you to pay money for that. You can download several
    free audio recording or dubbing software apps, record in .mp3 at the desired rate, and
    then copy and paste the completed file over to NextRadio's output folder for audio so
    you can play it back.

    No need to play it back using NextRadio. I just want to be able to
    capture the sound from it. I tried a half dozed audio capture apps, and
    none of them can capture the internal audio from NextRadio, or the
    reduced signal sent out the earphones and fed back (reduced) into the
    external mic input with. I even tried using a headphone with a mic, and
    taping one of the earpieces to the mic rather than resisters and a cap
    to feed the signal back, and neither one works.

    One of the recorder apps shuts off the NextRadio output when recording,
    the others just have 0 volume input despite the signal going into the
    external mic input, or they just record whatever the internal mic hears.


    Or you can record it in 16 bit Stereo wave format (.wav) file, convert it to .mp3 format
    you desire to convert it to with a convertor. Then dump the file into NextRadio's
    output folder to playback the finished .mp3 file. In this way, you can bypass the
    software you speak of stringent requirements and pedantic quirks.

    FYI, sometimes, there is a DRM (Digital Rights Management) on these files or software
    that play them to prohibit copying copywritten files. DRM is a form of a "copy" guard,
    again because it boils down to the fact that they want you to pay money to get the
    composite signal that comes from them. I just provided you work arounds without
    the cost and the hassle; I also warn that this post is for educational purposes only
    regarding recording and conversion of signal and is not an encouragement to violate
    any copyright or infringe upon anyone's work in any other form otherwise.

    Good luck,

    Charles Lucas

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