Originally Posted by
Prboz
Hmmm I don't use my DX7 any more. I lost 2 planes and almost a third. 3 different receivers and battery packs. Think my Transmitter has an intermittent fault. Bound with another DX7 with my trainer after Imanaged to get it to the ground and didn't have any issues after that.
My 2c worth
the DX7 was notorious for this sort of issue, however the OP is using a DX7S, different animal entirely.
IMHO Jester_s1 and Rob2160 hit the nail on the head... Check both the receiver and satellite position / antenna including the connector to the satellite.
EDIT: additionally, check the connections between the battery and receiver including the switch for anything loose / intermittent.