RE: DX-7 related crash?
I'll offer this as a possibility. On/off switches are the one truly weak point in any radio system. A switch that works fine on the ground may fail during flight (and then be just fine back on the ground). I've had it happen where vibration causes the switch to intermittently disconnect. THAT particular problem nearly drove me insane trying to find the glitch (with an old Tower Gold Case back in the day). I don't use any switch at all anymore, I use two aileron extensions as a 'switch'. Plugged together, and it's ON. I put it underneath a small hatch with a magnetic closure so there's no chance anything can snag it.