Archive for July 26th, 2017

Byonics TinyTrak3+ vs. RFI

Some weeks ago, the APRS + voice adapter on my radio began randomly resetting during our rides, sending out three successive data bursts: the TinyTrak power-on message, an ID string, and the current coordinates. Mary could hear all three packets quite clearly, which was not to be tolerated.

I swapped radios + adapters so that she could ride in peace while I diagnosed the problem, which, of course, was both intermittent and generally occurred only while on the road. The TinyTrak doc mentions “… a sign of the TinyTrak3 resetting due to too much local RF energy”, so I clamped ferrite cores around All! The! Cables! and the problem Went Away.

Removing one core each week eventually left the last core on the GPS receiver’s serial cable, which makes sense, as it plugs directly into the TT3. The core had an ID large enough for several turns (no fool, I), another week established a minimum of three turns kept the RFI down, so I settled for five:

KG-UV3D APRS - ferrite on TT3 GPS cable

KG-UV3D APRS – ferrite on TT3 GPS cable

Prior to the RFI problem cropping up, nothing changed. Past experience has shown when I make such an assertion, it means I don’t yet know what changed. Something certainly has and not for the better.

I swapped the radios + adapters and all seems quiet.