I got this from one of the developers on the ExpressLRS discord
“even if you don’t use ch5 on the drone itself, you need to toggle ch5 on the radio to let the module know you’re armed… doesn’t matter if it’s via a telemetry sensor (via logical switch and/or special function) or by toggling the ch5 switch manually… (it doesn’t have to be set on the craft itself)”
No surprises there - they’ve consistently recommended that. That’s why I use an EdgeTX mix to set Ch5 upon stick arm/disarm. It’s the cleanest solution I’ve found.
I’ve got this working by getting the ARM telemetry sensor populated by Yaapu, then using an EdgeTX special function to send it back to the AP over Channel 5. Thanks @robertlong13 for the suggestion and help.
Works great - and Channel 5 is correct whether armed via sticks, switch or ground station and whether disarmed using any of these methods.
I think it should work if disarmed automatically (e.g. after landing), but I haven’t tested that yet.
I would add a long delay to Ch5 “disarm” so it stays “armed” significantly longer than it takes to disarm the vehicle.