I’ve read through all the forum post on TXMOD, SBUS, and Yappu and that’s been super helpful and great stuff. But I have a problem i haven’t seen before and could use some input from the group.
When I have SBUS configured my servos are twitching in my plane. I can see the twitching on the channel monitors on Mission planner, but not on the monitors on the Radiomaster. When I turn off the radio/ txmod the twitching stops. When I switch to PPM it stops.
I put some chokes on the servo wires and rfd wires.
I changed the RFDUX (airunit)
I moved the antennas away from servos
I turned the power way down
Checked firmware
Checked settings- works on another plane my friend has with the same parameters
I’m thinking its some grounding issue or weird interference I don’t under stand. I’m hoping is some dumb issue right in front of my face that someone can point me to
Hi. I have same problem. my setup is TX16s->TXMOD—>rfd868x–> Cube Orange+ RC IN. Usually problem starts in few minutes after reboot TX16s, this is how RC channels looks for FC(I am not moving gimbals)
Also I tried exclude RFD modems from signal path by direct connection(wired) TX16s SBUS and GND pins to Cube Orange RC IN. In this scenario everything working perfectly:
I am using 900mhz version. I ended up setting up PPM just so I could go fly, I will eventually go back and figure out why SBUS if giving problems but PPM is not. I can’t confirm at the moment but I am pretty sure the problem would stop when I turned the Radio master off. Which doesn’t narrow it down much but does narrow it down a little.
@amilcarlucas Thanks, I read this before and I have the same configuration, just running latest firmwares(txmod 1.4.8, rfd 3.57). In my case SBUS works in general, the problem is random spikes in channels. Have you faced with this problem in your setup? I also tried PPM and it works perfectly.
I made few tests with different refresh rates and looks like it doen’t affect anything. I turning on Tx16s and after 30s-5min I starting to see spikes.
Works OK on Taranis and TX16S.
Also good for RFD’s without using a TXMOD, no problems downloading logs
I cant say how the increased rates affect range because I cant get the damned things to go out of range
How can I improve the performance of my R/C signal pass through?
Due to the nature of the RFD modem communications, there may be a noticeable jumpynature to servo movement and a perceivable latency in the R/C signal. Depending on the telemetry data requirements you can help to reduce these issues
somewhat by reducing the MAX_WINDOW parameter from the default of 131 to as lowas40 depending on the air rate. This can reduce the data throughput somewhat so theuser
may have to experiment to find the settings that best fit their use case.
