Over in the FrSky thread on RCGroups Radio forum, it was recently brought up that it appears the PPM signal of most transmitters is at a higher voltage level than the specification for the IC receiving this signal in the FrSky modules. It appears that this IC has some diode protection with a current capacity of 2ma, per that thread. Various circuits and voltage divider schemes have been posted in that thread with the goal of protecting the IC from being damaged and possibly causing the module to die. I believe FrSky posted not only a circuit that could be used but were going to incorporate it in all future manufactured modules. So the question is, how safe are all the modules that are currently out in the world??
I've got both a non-telemetry and telemetry module, both of which have this "issue". I've flown with the non-telemetry module in a glider for a while now with no issues using a JR XP9303 but now I'm wondering how safe is this to do??? A destroyed model I can live with but possible collateral damage, such as hitting someone, is another ball of wax. For me, I'm grounding FrSky till I can get some sort of assurance that this really isn't an issue but is sure sounds like it is.