RSSI only showing 0% or 100%

Hello, I’ve been having a lot of problems on arduplane 3.8 to get rssi from my dragonlink.
I used to put a wire between my rx and pixhawk like with the APM which worked great, however on my new config, I decided to get rid of the cable and setup my dragonlink rx to output rssi on channel 8 within the ppm stream.(my flight modes are on ch5)

In Mission Planner, I correctly configured rssi_chan=8; rssi_type=pwm; min_pwm=1916 max=1992.
I f I check in radio calibration, I can see this channel moving constantly like it should, however when I look in the Quick view datas as well as on my osd, the rssi is 0% when radio turned off, and 100% when turned on, there is no middle value.

I could just plug the cable back but I’m to frustrated from not making such a simple thing work.

Clement_FPV,

While it my be a typo, you need to have min_pwm equal to something like 1000, not 1916.

DragonLink’s RSSI does not behave like a real “RF” type RSSI value. DragonLink’s RSSI is actually the result of a calculation that includes some aspect of data quality as well as the received signal strength. It generally does not begin to reduce from its 100% value until several miles out - only then does it begin to reduce by the usual 6dB each time the distance is doubled.

Try unscrewing the transmitter antenna and you should see a value between zero and 100. Put it back quickly lest you damage the transmitter.

Good luck,

Paul

Hi, yes indeed it is a typo it’s 1092 as min.
As for the DL signal, it definitely isn’t the explanation, because first I was out several miles yesterday with 100% (I usually go down 65% ln this route I usually fly), and also I tried unscrewing the antenna in the 25mw mode of my transmitter, I can see the channel in radio cal moving as it should but no the rssi.

Also, this is a fresh new firmware install because of other problems. On my previous install it simply didn’t even work at all…

Thanks for your help

Do you have Arduplane rssi_type=2 (rcchannelPWMvalue)?

Yes.

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DragonLink may have done something new with the latest software (Nov26) than what was before.

I am a new DL user and began with the Nov26 release - I thought rssi wan’t working until the RCG forum feedback said to expect the special DL presentation of what they still call rssi.

.

Hi, the thing is since the channel moves correctly in the radio calib page I really believe that the problem is coming from arduplane and not DL.

What channel are you using for rssi ?
Also, can you see the rssi move live on the quick view page of Mission Planner ? Because on mine, even if I turn off the transmitter I have to switch back and forth from another tab to see the rssi go from 100 to 0

I am using channel 8 and tell the Pixracer with Arduplane 3.8.3 to look for the RSSI on channel 8.

I never looked in the quick view page, but I can see the channel 8 PWM value move from 100 to 0 and back to 100 (ish) again on the status page when I turn the transmitter off and then back on again.

Did you change the SR1_RC_CHAN parameter to 1? Noircogi’s DL/MP instructions say to put it to zero (0), but he uses an OSD. For Mission Planner the parameter has to be set to 1.

Hi, I just reinstalled MP with a new version and it seems to work for the moment.
Very weird but go figure sometimes.

Anyway thanks a lot for helping me.

Clement

Ok, excellent. Good luck and may the software gremlins lay low while you are in the air.