PTT not engaging with APRS droid

I have the Digirig hooked up to my android phone, and am running APRS Droid. I know that at least the audio out part of the setup works, as if I hold the PTT button on my UV5R, it will send the packet(and can be heard on another HT). But I am unable to get it to engage the PTT for me. I know in direwolf and other progs, you have to tell it how to do that. I don’t see such a thing in APRS droid. What am I missing here? I know it is all wired up right, as I can send PTT fine from Direwolf on my PC.

For PTT transceivers not capable of CAT control, Digirig uses RTS signal of the serial port as a trigger. The software must support this option. Here is the list of the Android apps that does it:

As a fallback method where it is not supported, you can use the VOX feature of your transceiver.

I found this post in my search as I was having the same problem. I am running a similar setup of Android phone<>usb-c to usb-c<>digirig<>home rolled cable per K0TX spec<>Baofeng UV-5R.

The way I got my PTT to engage was by adjusting the multimedia volume on the phone (currently 100%, or max out) and VOX setting (menu 4) on the Baofeng. Currently VOX is set to 10 . This combination enabled the PTT to engage when I “send position” in APRSdroid.

These settings also fixed the problem for me where I would “start tracking” and immediately the radio would start transmitting. Adjusting the VOX to 10 solved this issue as well.

I just wanted to log this as a data point and what settings worked for me. Hopefully this will be of use to someone encountering the same issue.



I use this cable on my Feng-APRSdroid and DigiRig, but with no luck so far. Did you use the same cable?


I have the audio maxed and the VOX set at 10, like you did. But still can’t get everything to work. Can you please share your APRSdroid settings? I think this is where I am messed up. Thanks.

Boyet 4F3BZ

Same problem here. I have a TM-V71a with the Digirig cable set. If I manually key the mic and press send location it works because I get an acknowledgement. There is no PTT option in the app and the TM-V71a has no VOX option that I can find.