forum.pistar.uk

My BER is jumping all over the place, no matter what Pi or Hat I use or how I adjust RF offset. While I can lower it a bit, one transmission will be 0.7 and the next will be 5.4. I'm using a MMDVM hotspot with a dual slot hat made by a reputable manufacturer. This only seems to happen with DMR and happens even with the simplest DMR config. All help appreciated!

You left off a crucial factor... What /radio/ are you using!

BER for your outgoing transmissions tends to reflect subtle frequency offsets between your radio and the RF module mounted on the R-Pi. Setting offsets in the RF module tweaks the center frequency used for Tx/Rx. A radio with less-than-stellar frequency control could be drifting to either side -- based upon anything (temperature is most likely, followed by maybe capacitive coupling to your hand or flexible wires). Not that this is the only cause for BER...

Thanks. I'm using an Anytone 878. I had already used MMDVMCal, which resulted in a minor TXoffset adjustment, nothing that fixed the BER jumping all around.