The GPS from the Nesis is being used to feed the TRiG transponder. That is what the chap who did the installation told me. Don’t forget that the other aircraft, that overlapped with HMCF was also displaying a 2nm ring - I think that was a Fuji aircraft on EASA so there is definitely something not quite right here. I’m over today to look at what EDGA has as well as a fit - I seem to recall it’s a full RNAV fit, so I am more convinced there is probably a protocol or decode issue here (a ‘1’ or ‘0’ in the wrong place).
You may recall Lee posted a picture of this when he first saw it - this of another aircraft.
He’s also posted some separate received NACp figures in this thread, which would appear to be from a different device to a SkyEcho:
CODE: SELECT ALL
G-BDFR // NACp=2.0nm
G-HMCF // NACp=2.0nm
G-EDGA // NACp=10.0nm
So I think there is definitely something not quite right between some GPS and transponders
or they are transmitting on a slightly different protocol?