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I would like to be able to connect my radio to my computer in order to record audio. It seems like this would just be a matter of getting the right cable, but after trying a few cables (listed below), I'm realizing it's not that simple. I would like to be able to record audio so that I could save morse to practice decoding, record call signs so I can update a log book later on, and - somewhere down the line - be able to do something like record connections with satellites / ISS).

My Setup

  • Baofeng UV-5x3
  • MacBook Pro running High Sierra (10.13.5)

What I've tried

I have naively attempted to use these cables to connect to my Mac:

In both cases, the Mac doesn't receive any audio. Thinking that the issue might be with configuring the Mac's audio, I tried connecting each cable to my car's auxiliary input (which I can use to play audio from my iPhone). There again, I didn't hear anything from the radio.

After searching online, I've seen a lot of people just use their computer's external microphone to record audio. It seems like there should be an easy way to send radio output directly to a computer, though.

Related

I found that these existing questions provided interesting information, but didn't quite answer my question:

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  • $\begingroup$ The audio connector on a mac (TRRS + optical, "let's cram everything into one connector like it's a phone") is not the same as you'll find in a car (TRS stereo line in). $\endgroup$ – Phil Frost - W8II Jul 15 '18 at 20:48
  • $\begingroup$ Last I knew Mac's also have line level mic inputs too. $\endgroup$ – Don Rhodes Jul 15 '18 at 20:51
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    $\begingroup$ Current Macs have only a 4-contact (TRRS) jack which operates like the one on a cell phone — mic input (with bias voltage) only. $\endgroup$ – Kevin Reid AG6YO Jul 15 '18 at 22:28
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    $\begingroup$ This does not provide an answer to the question. Once you have sufficient reputation you will be able to comment on any post; instead, provide answers that don't require clarification from the asker. - From Review $\endgroup$ – Glenn W9IQ Jul 16 '18 at 11:47
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    $\begingroup$ by the way, since these things are really cheap, you could just use an RTL-SDR dongle, and record like a lot of channels simultaneously without your Baofeng handheld, for very comparable cost to building your own for baofeng audio->mac audio $\endgroup$ – Marcus Müller Jul 16 '18 at 12:25
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I built an audio interface that connected from an HF radio to my Mac, a few years ago. Obviously, I was concerned with ground loops and hum and suchlike, because I intended to use the interface to transmit too, so I used audio transformers as well.

But the one thing I found that surprised me was that (as mentioned in comments by Kevin) the Mac has a slightly odd audio connection system. As Kevin says, it’s a TRRS arrangement, but in order to make the Mac ‘see’ that there is a microphone connected, you need to put a diode between one of the Rings and ground. This is to allow the macOS to detect whether a microphone is present or not, and thus enable incoming audio.

I just used a regular small-signal silicon diode (1N4148 I think), and suddenly the Mac could ‘see’ that there was an audio input and allowed incoming audio through.

Use a continuity tester on a pair of Apple-compatible headphones with a microphone to determine which Ring should have the diode, and which way round it should be.

Of course, to be ultra-paranoid about the safety of your expensive computer when connected to a famously ‘cheap’ radio, you might want to consider an audio transformer too :)

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  • $\begingroup$ Based on the answers I've read, it sounds like there aren't any cables that you can buy to make the connection (but, instead you have to use a 'homebrew' setup like you've described here). Does that sound right? $\endgroup$ – Jim Jul 17 '18 at 20:09
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    $\begingroup$ Thanks for your answer here (and want to say thank you to everyone else as well). I think this will be a helpful reference if I can gather the supplies to try building a cable. Really appreciate the background information and tips! This was my first question on stackexchange and I was amazed at the quick replies. Thanks everyone! $\endgroup$ – Jim Jul 17 '18 at 20:11
  • $\begingroup$ You can buy them. Amazon sells Mac/iOS TRRS Audio adapters for guitar input. That’s what I use to test my Morse Decoder iOS app from a Yaesu. Here’s one: amazon.com/gp/product/B00M416TV2 $\endgroup$ – hotpaw2 Jul 21 '18 at 5:38

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