Servers by jDrones

Long range UAV link 100mw for 60KM was designed and tested


(Tom-fly) #205

I updated Missionplanner in the 1st laptop to version 1.3.60 and no more problems! So MissionPlanner 1.3.59 was the problem.


(RickyG) #206

Thats great news.
Thats three of us now as known users. The Skydroid family is growing.


(Tom-fly) #207

Familymeeting here :smiley: nice. It is pretty promising product yes. Btw, I started to make telemetry cable (is that needed at all? Any telemetry data wasn’t received via SBUS RX . Do I need actual cable to make it work ? TM cable which came with M12L isn’t compatible with Pixhawk 4 :frowning:

Here is cable pinout of Pixhawk4 telemetry port, do I need to swap rx&tx in cable ?


(RickyG) #208

yes you need the cable. The Flight controller will send the Mavlink telem to the receiver and that will get routed back. It seems to work very well in my tests. What was a big surprise for me was RSSI. It provides RSSI data back to the ground station via the link as well. No need for a separate RSSI connection.

remember to reverse the FC-RX always goes to the receiver TX and the FC-TX to the Receiver Rx.


(cala2) #209

Wow!! I´m going to have lot of work done when I recive mine, thank´s guys :slight_smile: , Im waiting a Mini talon to test distance :smiley:


(Tom-fly) #210

great, please let us know how your project goes on. What fc you are going to use? I soldered cable for pixhawk&rx and all the data is moving fine. Qground controll seems to work as well in android without problems, so you dont need original software in phone.


(cala2) #211

I have an Auav X2.1 for the Talon and installing a Pixracer on my longer endurance quad to lightweight it for longer endurance.


(Tom-fly) #212

I configured Pixhawk 4 and M12L to work together and tried arming. First, it didn’t work. I had original values from previous radio, so I calibrated the radio. Everything went fluently except calibration in Missionplanner gave wrong min/max PWM values for RC15_trim and RC16_trim, so those values had to be changed manually in parameters.
Calibrated parameter for value was 870 pwm for trim (both rc15_trim & rc16_trim) , so compass/motor calibration didn’t gave correct values and arming the aircraft was impossible because minimum accepted value was something like 1000 pwm. I dont know if that is Pixhawk4/MissionPlanner based issue, but just defining those manually to value 1051 pwm, and arming was possible. Conclusion, calibration didn’t work correctly and values were out of real range. Maby MissionPlanner issue again :smiley:

I didn’t try QGroundControl in laptop if that works with different way in calibration. Afterall gps, compass and all the telemetry data seems to transfer nicely with M12L and arming happens like a charm. I used QgroundControl and MissionMaker for Android in phone, because original software had Chinese terms for flying modes and I didn’t wanted to take risk if suddenly I have to change flying mode with groundstation (phone) :slight_smile: Finally , I hovered copter few minutes in stabilized mode and nothing problematic occured. Only issue is, RX is pretty warm even TX is only only few meters from it. Would it be possible to set dynamic/flexible transmission power like Frsky is using in long range systems ? Maby that is not issue but dynamic transmission power would save battery in big way…

So next I’ll start planning range tests…


(RickyG) #213

Wa hooooo…great news.

You lost me a bit on the PWM value. I got the same error about the trim, so please tell me what you did exactly to correct it. Also did you say you needed to set the bottom end of the pwm range on the transmitter to 1051. I have never heard of that before, my bottom end is typically 1000.


(Tom-fly) #214

Yes, you can see correct values from Missionplanner, “Initial setup” -> “Mandatory hardware” -> “radio calibration”… there you can see the valueranges for all channels. Pixhawk 4 informed that rc15_trim and rc16_trim weren’t correct and all the minimum values under 1051, after trying “initial setup” -> “optional hardware” -> “compass / motor calibration”.

So you can alter values from “config/tuning” -page…


(RickyG) #215

Ah yes I get it.
Odd that Mission planner/Pixhawk would do that. You would think it would have known that. Also since this is a 12 channel RC receiver, why are 12 and 14 not wrong or is it a 14 channel and I read it wrong.


(caoxueyu) #216

We are not using the 13-16 channel. So give SBUs the lowest value. By updating the firmware method, the 13-16 channel can be output 1000, so that no pix error can be reported. I will release firmware and upgrade tools to you.


(RickyG) #217

Super thanks caoxueyu


(Tom-fly) #218

wow, thank you! by editing manually those values takes few minutes, but much better to automatically identify correct values


(RickyG) #219

Hey any plans to go and use 13-16


(caoxueyu) #220

I’m busy developing a camera. So maybe a few days later. You can switch the receiver output to ppm mode


(RickyG) #221

Sorry caoxueyu what does PPM get us.
Honestly I don’t know what PPM is as I have always used SBUS or PWM and my machine I am going to use this on has an Frsky Sbus to PWM decoder, perhaps it does ppm as well. I guess I could look. But still what does ppm get us.


(caoxueyu) #222

The SBUs pin of the receiver can be used to modulate the PPM signal with device helper. But there’s only 1-8 channels.


(RickyG) #223

ok thanks.
I will stick with SBUS and not ppm.


(Tom-fly) #224

Hi, I uploaded this tiny help if that helps something until we get firmware without extra channels.

ardupilot_problem.pdf (257.3 KB)