Mission planner and Pixhawk not seeing Radio off so will not go into fail safe

[Paul-H]

hi all

Got a bit of an odd one going on here.

I am trying to configure the Fail-safe option, but Mission Planner/Pixhawk does not detect when I turn the radio off so it will not trigger Fail-safe.

If I start mission planner with the radio turned off, it correctly shows no radio and as soon as I turn it on it correctly shows its connected but as soon as I turn it off to trigger a fail-safe the screen still shows the radio is connected even though its off.

I am using a Turnigy 10 Channel system connected via PPM, all other aspects work but this one has got me stumped and is preventing me going out flying, anyone got a clue as what';s gone wrong here.

Thanks for any help

Paul

[BadgerG]

On the Taranis X9D you have to set the type of fail-safe to No Pulse in order for the receiver (X8R receiver) to output no pulses so the FC can detect that the throttle channel has drop below the normal low throttle value. This in turn is what triggers the failsafe. Otherwise the receiver will either use the center channel values or maintain the last know values. In that case the FC can';t tell that the receiver has lost contact with the transmitter. This may also need to be done on the Turnigy.

[Paul-H]

Ok found the fix

In the receivers failsafe setup only set failsafe on channel 3 and set it to its minimum value

In mission planner go to the transmitter setup page, on the transmitter set the throttle trim as high as it will go, this takes the minimum up above 1000 then calibrate the transmitter. this locks the high trim level as its new minimum about 1100 in my case.

Then set the failsafe trigger to just below the new minimum figure eg 1090.

Now when the radio is switched off the throttle signal drops back to 1000 and the failsafe triggers.

Hope I remember to do this the next time I build a model