Thanks for the reply. These are the Airtronics recevers I've had since I got this radio, one came with the radio and the 2nd is Airtronics 92777/ 72 Mhz FM, a flight pack I bought a little later. Both have worked in the past but neither works anymore. Batteries fully charged ( I have 2 receiver battery packs) and the transmitter turns on but the receivers do not. In the past, this radio would work sometimes and sometimes it wouldn't. Never been able to confidently use it to fly the heli. Bought the receiver pack to put in the P-51 from Top flite ( not Great planes as I said in my original post) and have not finished that . I have 3 of the older VG6DR 6 channel radios that I've never had any problems with, but this one has been a real let-down. Sorry now that I bought it.