Greetings,

I have a PAUL board connected to a Kenwood TM-271a via the internal pads (not the mic/speaker connection)
https://www.arcomcontrollers.com/documents/rc210/tm-271a_mod.pdf

- RX works, I can decode APRS messages without issue.
- PTT seems to work, at least the radio goes into Busy state (but doesn't show OnAir - not entirely sure if this is correct or not)

TX is where I run into the issue. I can trace the audio signal to the PKD pad of the radio but a nearby HT doesn't pick up any signal.
Windows Sound settings are all at 100% and I turned the Audio out Pot to max signal.

Does anyone know if the PAUL board has enough drive for the internal data connector of the TM-271?
is PTT acting correctly (busy instead of OnAir?)

Thanks

73,
Marcel

开云体育

Hi Michael,

Thanks - no, I don't have a power meter (yet) but I can measure how much power the radio consumes - should give some indication re TX Power.
What I could do is to use a signal generator set to either Mark or Space Tone and slowly increase the output voltage to see if I get the radio to transmit into a dummy. Apparently a nearby HT should pick this up. Power draw from the radio should start to increase eventually.
Question is how hi can I go. I've seen some TNCs going all the way to +/- 4V on their audio output.

Thanks
Marcel

Update - in case someone else stumbles over this thread.

Got it to work via the front RJ45 connector and the Speaker Port in the back - for now. This will be limited to 1200 but it's a start.

Connected the Radio to a 40db directional coupler -> dummy load and the tap via an additional attenuator to a TinySA. The SA has a FM measurement mode that helps to set the audio levels of the PAUL board correctly. (I've been told that? deviation of 3.2kHz is about right)

And that's about it. Still trying to get it working via the internal pads to get 9600 but at least now I have a working setup.

Thanks to all the chimed in.

73 - and Happy New Year
Marcel