BTECH APRS-K1 Audio Cable

Aloha, does the BTECH APRS-K1 Audio Cable work with digirig. It would be nice not having to buy another cable. the tech uv 50 comes with a K1 adapter.

@WH6GXZ I do not know. I will take a look at my K1 APRS cable…

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If it is compatible then it is purely accidental. The pinout would have to be compared.
Here’s the pinout of Digirig’s K1 data cable:

The pinout is different. baofang claims it will work on anything. I saw the guts of baofangs K1 APRS cable - results may vary…

One could pick up a couple TRRS breakout boards if we knew what the pinout was on the Btech cable.

Which ones do you use? I use these, but I’m not happy with them: Kework 5-Pack 1/8" 3.5mm 4 Pole TRRS Stereo AV Female to 4-Screw Terminal Stereo Female Headphone AUX Balun Connector Converter Adapter (FM/FM) : Electronics

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I haven’t tried yet. I just found out about them researching a way to use my 50x2 gen 1 as an AllStar node. I come across them being used as a cabel converter for A digirig/Mobilinkd with the attached video.

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BTW: this adapter is available in store:

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The only times I’ve used the K1 cable, it’s been with a Sabrent USB sound card, activating PTT with VOX. When using Digirig, I just keep my life simple and I buy the digirig cable corresponding to my radio.


In case anyone is still interested - I took my BTECH-APRS-V01 cable apart, did some metering, and drew the attached schematic. It doesn’t match other drawings of Baofeng HT cables I have seen, and I don’t fully understand how it works. In fact I rechecked the little circuit board 3 or 4 times.

Not familiar with this cable, but it looks like it connects K1 to CTIA headphones/mic pinout with attenuators and DC/decoupling to bring levels from headphones to mic levels. Similar + PTT implementation can be found in Digirig’s PTT cable:

I bought that BTECH cable abt 3 years ago when I was looking for a way to connect one of my Baofeng BF-F8HP’s to a laptop for APRS tracking purposes. I couldn’t get it to work and ended up building my own cable to connect thru my Signalink instead. That worked fine at the time.

I just bought a Digirig and cable for my IC-7100 thru Amazon. While waiting for it I got curious about this BTECH cable I had stored away. Not that I’m going to use it for anything, but later I might want to do something with my Baofengs. Good to know you have a cable that does work.

For now I’ll be using the Digirig between a Desktop PC and my IC-7100 as an APRS beacon, Digipeater, etc. I have been using my Signalink for that purpose but dislike all the noisy chatter its relay makes. Hence buying a Digirig.

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Sounds like a plan. Heads up that Digirigs sold on Amazon are in logic levels (default) configuration. If you plan to use serial CAT control of your ICOM then you’ll need your Digirig reconfigured for CI-V.

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