Need help troubleshooting no PTT

Hi everyone,

I have the Digirig connected to the a Yaesu FTM-300DR using the 10 pin mini Din connector connected to the audio port of the Digirig. This is all connected to a Microsoft Surface Go 3 via usb c. Things were working great for 24 hours, until there weren’t.

I fired the system up today to do some more testing using Winlink and Vara FM. The radio would not transmit. No PTT.

  • Power cycled radio and rebooted Surface Go, no change.
  • Turned on “listen to this device” on the Recording tab of the USB device assigned to the Digirig. No sound.
  • Connected the Digirig to my FT5DR with the Yaesu cable the I purchased from Digirig last week. Sound came through to computer fine.
  • Tried to PTT the FT5DR. No luck. Now, to be fair, I had never tested this to know if it worked or I had the radio setup properly. I was just happy to get audio.
  • Switched the Digirig back to the FTM-300DR. Reconnected both ends of the interface cable between the radio and Digirig. Noticed when moving the cable slightly on the Digirig end, I get static and ground hum. Perhaps bad plug on Digirig board?
  • Reconnected the FT5DR. Wiggled plug. No static or ground hum. Audio rock solid.

So my conclusion? Bad cable between FTM-300DR and Digirig.

Any other troubleshooting you think I should try before I call Gigaparts for a replacement?



If cable proves to be faulty, I can handle the exchange for you.
Now, using the continuity tester please check if the lines are all connected. Note that the drawing is for the solder side. The pinout is mirrored when looking from the outside. Use wider gap between pins 8 and 9 as the clue.

There is also a quick and dirty way to test the PTT function, see here:

This was very helpful. Thanks.

I did the quick test of shorting the sleeve with the closest ring (R2). No PTT.

I then checked continuity of all pins. R2 to pin 3 of the mini DIN 10 connector does not have continuity. The other 3 checked out fine. I’m surprised that I’m not hearing audio since pin 1 checked out. But I never tested that before when it was working on this rig (only on the FT5DR).

Please let me know how you’d like to handle the replacement.

Thanks again for your quick help.


Please DM me the order information and I’ll send you the replacement cable.

Thanks for the prompt replacement Denis. Received the cable yesterday and everything is working great!


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