Hello,
Something happened with my Mobula6. In the googles shows "rxloss", the controller says "rx signal critical". It worked perfectly yesterday. I re-binded the drone with my controller, but it still doesn't work. In betaflight the signal from the controller lags, and when it's lost it sets to 1500. See the video: https://imgur.com/a/Uw0Nuuj
I didn't crash with it so i don't now what happened. Yesterday it worked properly. Could it be that the antenna was damaged? If yes, how can i repair it?

Here are some images of the antennas:
https://imgur.com/a/OXZfDJQ

The antenna looks OK to me but I would remove the canopy and carefully inspect the solder joint in case it has cracked which can make for an intermittent connection. It's not always easy to see with the naked eye so use a magnifying glass and wiggle the antenna wire to see if any type of minuscule crack opens up. If in doubt, re-flow the solder for the antenna wire.

I will check the solder joint. I rebinded the quad with the transmitter again and when i conenct the battery i can arm, but as soon as i increase the throttle the telemetry is lost. In BFC i can only see the signal from the transmitter for 2-5 sec and after it losts and the numbers sets back to 1500.

Here is the status of the quad with the transmitter turned on. When i tried it the signals were lagging a little but i didn't lose telemetry


System Uptime: 15 seconds
Current Time: 2020-03-31T17:26:34.212+00:00
Voltage: 3 * 0.1V (0S battery - NOT PRESENT)
CPU Clock=96MHz, Vref=3.26V, Core temp=35degC, GYRO=MPU6000, ACC=MPU6000
Stack size: 2048, Stack address: 0x2001fff0
I2C Errors: 0, config size: 2559, max available config: 16384
CPU:28%, cycle time: 131, GYRO rate: 7633, RX rate: 60, System rate: 9
Arming disable flags: CLI MSP

The CPU cycle doesn't look particularly over-stressed. Try running the "tasks" command in the CLI and see what it comes back with. That shows the real CPU loading for each task.

If the antenna is OK then this is sounding like a hardware issue to me. The Mobula6 uses the Crazybee F4 Lite flight controller with integrated SPI receiver. I'm wondering if there is some kind of voltage regulation issue on the board for the receiver circuit. The Crazybee boards have a known history of failed voltage regulators although I thought they managed to get on top of that issue now. Maybe it's just a QC issue with your particular board.

It might also be worth trying to re-flash the Betaflight firmware just to eliminate any firmware issues. Don't forget to take a "diff all" of your current settings first and save a copy somewhere safe.

So i resoldered the antenna. After that i was able to fly like 3 round in the room. But than it said rxloss again and the quad fall. What now? Add more solder?

Unless you made a bad joint with your re-soldering then I think maybe what you did was maybe just a fluke. What does you re-soldering look like? Are you using flux and proper leaded solder (not that lead-free rubbish)?

I think the soldering is decent. https://imgur.com/a/sSmK7zg

I set the protocol to dshot300 i was able to fly a little again. At first everyhing was okay i only got rxloss for a second, i flew a litle more, i got rxloss again for a second and then when i reach the middle of the room i got full rxloss and the quad fell.

Please run "tasks" in the CLI and copy/paste the results back here.

Task list rate/hz max/us avg/us maxload avgload total/ms
00 - ( SYSTEM) 9 2 1 0.5% 0.5% 0
01 - ( SYSTEM) 956 3 1 0.7% 0.5% 15
02 - ( GYRO/PID) 7633 87 67 66.9% 51.6% 12418
03 - ( ACC) 959 18 9 2.2% 1.3% 232
04 - ( ATTITUDE) 99 16 11 0.6% 0.6% 30
05 - ( RX) 32 85 68 0.7% 0.7% 62
06 - ( SERIAL) 99 311852 248 3087.8% 2.9% 585
08 - (BATTERY_VOLTAGE) 49 7 3 0.5% 0.5% 3
09 - (BATTERY_CURRENT) 49 2 1 0.5% 0.5% 1
10 - ( BATTERY_ALERTS) 4 3 2 0.5% 0.5% 0
11 - ( BEEPER) 99 7 1 0.5% 0.5% 3
16 - ( OSD) 59 477 59 3.3% 0.8% 83
18 - ( CMS) 59 5 2 0.5% 0.5% 1
19 - ( VTXCTRL) 4 72 11 0.5% 0.5% 2
20 - ( CAMCTRL) 4 2 1 0.5% 0.5% 0
22 - ( ADCINTERNAL) 0 3 1 0.5% 0.5% 0
23 - ( PINIOBOX) 19 2 1 0.5% 0.5% 0
RX Check Function 23 5 3
Total (excluding SERIAL) 79.4% 60.5%

There is nothing out of the ordinary with CPU loading for the tasks. It could be a problem with your transmitter or the antenna on it. Which transmitter do you have? And have you ever run the transmitter without an antenna fitted, or replaced the antenna on it at all?

I have FrSky Taranis Q X7. I tried the transmitter with my 5" quad, i didn't fly with it just armed it and spinend the motors a little. This was when i could even arm the mobule6 because i got rxloss as soon as i plugged in the battery. To be honest the batteries of my transmitter are low. I ll buy some new tomorrow. Could this be the problem? I never messed around with the antenna on the transmitter

Your transmitter should still work OK down to ~6V. What voltage are you batteries showing?

If it works fine with your 5" then it's looking more and more likely to be some kind of hardware issue with the SPI receiver on the Mobula6 itself.

As a last resort I would try re-flashing the Betaflight firmware to it as mentioned in post #5.

I m at around 6.5 v.. I try reflashin tomorrow. Thanks for the help