No radio signal, radio failsafe on

Hi guys,

I’m trying to make a drone from Udemy course but I faced an issue with arming. After few seconds that I connect battery, LED on Navio starts blinking yellow, Mission Planner outputs such messages:

8/21/2020 11:36:29 AM : PreArm: Radio failsafe on
8/21/2020 11:36:29 AM : PreArm: Compass not calibrated
8/21/2020 11:36:29 AM : PreArm: Compass not calibrated
8/21/2020 11:36:29 AM : PreArm: Throttle below Failsafe
8/21/2020 11:35:59 AM : PreArm: Radio failsafe on
8/21/2020 11:35:59 AM : PreArm: Compass not calibrated
8/21/2020 11:35:59 AM : PreArm: Compass not calibrated
8/21/2020 11:35:59 AM : PreArm: Throttle below Failsafe
8/21/2020 11:35:43 AM : Frame: QUAD
8/21/2020 11:35:43 AM : ArduCopter V3.6.11 (296c62b3)
8/21/2020 11:35:43 AM : Frame: QUAD
8/21/2020 11:35:43 AM : ArduCopter V3.6.11 (296c62b3)

And so on. Transmitter is turned on. I am sure that receiver and transmitter are ok, because they work when connected directly to ESC. Receiver is powered, its LED glows red when transmitter is on.
Also ESCs are beeping continuously, I suppose that’s because there is no radio signal.

Hardware:

  • Navio2
  • FlySky FS-R6B receiver
  • Pixhawk PPM encoder

Software:

  • ArduCopter V3.6.11
  • MissionPlanner 1.3.73

Hi Max,

Thanks for your patience.

Could you please clarify, have you completed the calibration in the Mission Planner? This guide shows how to do it.

Please share the screenshot of Mission Planner upon finishing it. With that, we will be able to see what’s going wrong.

Hi Artem,

Thanks for your reply.

Well I cannot finish calibration in Mission Planner because the drone receive no radio signal. Now I’m pretty sure that the problem is in PPM encoder, I checked it with multimeter and it seems that it sends no signal. I ordered a new one to try.

I’ll return to tell if the problem is solved.

Max,

Thanks for letting me know.

Please, keep me posted!