srcejon
commented
1 year ago I have actually been looking at a few of these. There don't appear to be any LORAN transmitters near me. Could also add:
NDBs (although you need dual antennas) DME (can't really do this without transmitting, but perhaps you could receive both the interrogation signal from an aircraft and then the reply from the DME and combine it with ADS-B somehow) RACONs (again, probably needs transmit).
Some additional ideas for navigation signal decoding:
DGPS beacons
LORAN / LORAN-C / eLORAN (not sure if used anymore)
Russian CHAYKA (similar to LORAN)
Russian RSDN-20 if it gets back into operation
GBAS for aircraft (not sure if this is interesting)
and why not the satellite systems GPS/GLONASS/Galileo etc. but these will be more complicated