Removed transponder a week ago out of a Cessna 182. I always get flight following in the Anchorage area and no problems with ATC receiving position, altitude and code. Took it to Northern Lights Avionics shop in Anchorage for a yellow tag. Avionics tech was unable to yellow tag it due to the receiver being slightly out of tolerance. A couple years ago I had work done to the transmitter section of this unit by Northern Texas Avionics and would highly recommend them, reasonable rates and great work. I called the guy on the phone that runs the shop and he said that if the receiver just needs to be realigned it would probably be about $150 to repair. If you buy this unit I can send it directly to you or a shop of your choosing to fix it.