3Gx v3.0 Servo Twitching Problem

[farmer]

I have a 3gx v 3.0 servo twitch problem. I am new to flybarless (trex 700n 3gx) It came with version 1.2 updated to version 3 and I have now got the cyclic servos and swash plate twitching randomly When stood motionless without me touching the controls. I have tried the following to correct, a new 3gx, a new power supply, unplug servos individually with no joy.
The only way I can resolve is revert back to version 2.1 or if I unplug one satellite which is plugged into antennae 1, this resolves the problem with version 3 but I don't want to fly on one satellite.
Just to let you know I am using spectrum dsmx satellite's and have exchanged one of those to see if that was the problem with no joy. I have rebound and reset up multiple times with no joy and also reflashed version 3 on another computer
Any help will be very much appreciated

[coolice]

Hey buddy.

What regulator are you using to power the radio gear? V3 is known to consume more amps so it could be a cause.

It's strange that there are two instances now that appear to be fixed by unplugging one satellite receiver. I've not seen or heard anyone else having this issue, so it's either a power supply or satellite/sat connecting wire problem.
Could you try plugging the removed sat onto the same wire as the one which works and let me know what happens? This may prove if it's a sat or wire problem.
.

[farmer]

hi, I have tried another power supply by plugging battery straight into 3gx 5000ah Ni-MH 6 volt and the twitch is still the same. I have also swapped the satellites round and also tried a completely different new satellite and it's still the same. The tail also has a twitch when you move the rudder stick left to right at about 75%. Both 3gx I have tried are perfect with 2.1
Thanks, have you got any other ideas?

[coolice]

Hey buddy.

Reading your first post again, you've tried another 3GX and it does the same on this model? If yes it points to another component on the model spiking the 3GX, a naff servo or something.
You're not plugging the power to the 3GX through a switch harness are you, I'm thinking of the 6 volt pack you tried at present?
Is the model powered by the NiMh battery normally? I'm wondering if the amp draw of the 3GX is too much for the NiMh pack if yes. I've not tried a 3GX on a NiMh pack to know, only 2s lipo regulated to 6 or more volts.

If the 3GX is new and I couldn't find anything obvious as the cause, I'd send it back for checking to be safe.

Have you tried a new fresh download of the pc software and firmware files? Its not impossible the download could have corrupted.
.

[anjki]

Same twitch here with dsmx sats. It seem as though the 3gx is sitting waiting for a command.
I have seen this same thing before with curtis gyros in the old days,and there were no probs there.


andy k

[farmer]

Hi yes the 2nd 3gx is also a brand new one. The batteries I've tried are the Align 2 in 1 Voltage Regulator Combo with 7.4 volt battery it came with. And the 6 volt NI-MH battery I plugged straight into the 3GX with no switch so that is two separate power supplies I've tried. I reinstalled the version 3 software on a completely new download on my brothers pc to see if this was the problem and it was exactly the same. I have just found this information on a google search from another guy just copy and paste the link.
Thanks again Issue with 3GX 3.0 + DSM2 Sat receivers + HV Servos Combo - HeliFreak

[farmer]

Hi I have tried a second brand new 3Gx and it was still the same.I have tried two separate power supplies the Align 2 in 1 Voltage Regulator with LI-Polymer 7.4 and also the NI-MN 6 volt plugged directly in to the 3gx with no switch. I have also re-installed the version 3 software on another PC and a brand new download and it's still the same.
thanks

[farmer]

just found info on this link. Issue with 3GX 3.0 + DSM2 Sat receivers + HV Servos Combo - HeliFreak

[coolice]

Hey Andy.

I was going to say is it a DSMX sat induced twitch when connected to the 3GX, but as it appears to go away when only one is connected I'm not sure now.
You dont have a pair of DSM2 sats you could try to see if the twitch is present on these older style sats? It shouldn't make a difference as the DSMX sats are backwards compatable, but it's got me thinking. Especially as the 3GX cannot bind in DSMX mode, only DSM2, so is there an issue introduced with V3 firmware and DSMX sats?

I'm trying to recall if there had been talk of the latest DSMX sats giving some strange problems on some systems? I'm not sure, just trying to work out a possible cause.
Could the 3GX on V3 be mishandling the 2 sets of signals it's receiving from the two sats?
.

[coolice]

As a test can you turn your gain pots on the 3GX down to say approx 10% and see if this makes a difference for me?
.

[anjki]

Hi Ian

Sorry no dsm2 sats to try,but mine also does it with both units i own on brand new sats.. Its an un used combo with new hv servos running my trusty jive so i am sure its not a problem with components.
I spoke to Phil about it, he said he had seen it on his camera ship aswell.
interesting....the plot thickens.....lol

andy k

[Andy from Sandy]

Same problem occurs when using DSM2 satellites

Issue with 3GX 3.0 + DSM2 Sat receivers + HV Servos Combo - HeliFreak

[anjki]

Ian
I have just tried it again,it was a couple of week ago since i set this model up on the bench.It only does it in dir mode on mine.
Dunno if that helps but the pots have no affect.

andy k

[Andy from Sandy]

Strange glitches in DIR setup with V3.0 - HeliFreak

[anjki]

Cheers for that Andy.
Interestingly it seems as though mine now has stopped doing it, which does seem to match some of these other reports you have found!
I will report back if any probs when flying the heli but untill then i am gunna fly the arse off it.

andy k