The message "CAUTION: Avionics power low" is 'normal' as DM said. It comes every time the motors will be armed. Seems to be a voltage drop at sensor due to motor current peak.
It's only a problem when it happens during flight, but this I have never seen up to now.
Test flight 00226 looks good so far, no RC drops. Flight behavior is good. Pitch stick is calibrated now. Compass calibration done. Here are the messages:
13706 00:04:05 INFO: '(3,26)ANGLE MODE'
22141 00:06:28 CRITICAL: 'CAUTION: Avionics power low: 4.71 Volt'
22143 00:06:28 INFO: 'Armed by RC.'
22144 00:06:28 INFO: '(3,14)home: 43.2295291, -115.9608103, 955.81'
22154 00:06:28 INFO: '[logger] file: /fs/microsd/log/2022-04-26/20_25_2'
22610 00:06:36 INFO: 'Takeoff detected.'
22670 00:06:37 MPC_REALSENSE : Type: 6, Index: 393, Count: 813, Value: $01=0000 0001
23715 00:06:54 INFO: '(1,7)Warn geomagnetic field is disturbed.'
44950 00:12:56 INFO: '(3,81) obs open'
45017 00:12:57 INFO: '(2,86) altitude Less than 1.5m, obs not available'
45076 00:12:58 INFO: '(3,81) obs open'
50790 00:14:36 INFO: '(3,51) BEGIN TO RTL'
50793 00:14:36 INFO: 'Flying straight to home'
50894 00:14:37 INFO: 'RTL: loiter 3.5s'
51439 00:14:47 INFO: '(3,26)ANGLE MODE'
51472 00:14:47 MPC_REALSENSE : Type: 6, Index: 393, Count: 813, Value: $01=0000 0001
51932 00:14:55 INFO: '(2,86) altitude Less than 1.5m, obs not available'
52200 00:15:00 INFO: 'Landing detected.'
52208 00:15:00 INFO: 'Disarmed by auto disarm on land.'
One message "Warn geomagnetic field is disturbed" after calibration during flight but never reported again. I think it is not a problem.
I wonder why the RC signal strength is going down before starting the drone. You moved away from drone but only a few meters. This should not result in that drop. Did you have the two rod antennas in 90° angle to each other at this time?
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