I’m afraid it’s a fault in the sketch. The library correctly returns a signed value, but for some inexplicable reason, it’s assigned to an unsigned.
You need to edit the sketch so that the relevant variables in the data structure being passed through to the radio are signed, and change the entry in emonhub.conf likewise.
I’ve answered this with full details not long ago, I’ll try to find it.
Here, I’ve corrected it for you:
EmonTxV3CM.zip (12.5 KB)
It’s an unofficial V1.8 Note the changed definition for the Node 15 in emonhub.conf in the comment at the top.
@TrystanLea This is a long-standing problem that needs correcting - emonhub.conf too.
@Bill.Thomson I guess this needs to be in the FAQ - at least until it’s corrected.