Ez UHF issues

[Jameskibler]

Installed an EZ uhf sytem into my skywalker the other day and maidened it today however something very strange kept happening. It kept locking up for a second and then regaining control only to lose it again after another couple of seconds and this was only at about 100 meters!

The Problem is EXACTLY the same as this guys: http://fpvlab.com/forums/showthread.php?2871-Zephyr-maiden-today!-EzUHF-issues-(video)

Has anyone has this happen to them? and how did you resolve it?

James

[Flyn]

Hi mate, sorry to hear you're having problems - have you used the spectrum analyser? What's your noisefloor with your plane switched on?

What gear are you using with it?

How is you gear laid out in the plane?

[Jameskibler]

Flyn i've literally just finished reading your thread on fpvlab about the Ezosd interfering and got me thinking. When i maidened the skywalker the other week with just servos, motor, esc, receiver everything worked fine but now ive added the FPV gear (EZ OSD, 600MW vTx and Camera) the issues have appeared!

The vTx is in right wing (5 inches from middle), The OSD gps is in the left wing (5 inches from middle), the Osd itself is under the wing in that little area above the fuselage with the current sensor under that in the fuselage. The receiver is on the tail boom about half way down being powered by a separate 5v bec connected to a 3s battery.

[Jameskibler]

Looking at your post the fingers are being pointed at the EZ osd but in other posts they've found that it was a faulty EZ uhf tx..  :(

[Flyn]

Looks like you've been doing some reading, good going, a lot of people don't.

If your UHF tx has the red bands around the top & bottom your tx is probably fine as the tx problem you're most likely reading about was remedied with that revision.

Sounds like your layout should be ok, pics would be good inc any of esc & osd & current sensor.

Way to tell if your ezosd is flooding your UHF band with noise is to use the spectrum analyser - btw you didn't awnser my 1st question about that.

You need to use it if not! ;)

You need to have the plane off & the analyser running, get a baseline reading then add a lipo to the osd current sensor (have the osd & current sensor disconnected from everything but each other) & move the current sensor near the ezuhf & see if it raises your noise floor.

[Jameskibler]

Haha, i will do all of the above and will be back later!

Thanks the the help mate  :)

[Flyn]

Cool, post pics of your graphs too please bud.

Not problem, glad to help. ;)

[Jameskibler]

Right firstly its the newer tx:



this is the setup:






1) baseline - rx connected to computer only:



2) servos and ubec powered up:



3) everything on including OSD, motor, esc, Vtx etc...

[Jameskibler]

Hang on, theyre the same graphs...

two seconds..

[Flyn]

Lol, was just gonna say ;)

[Jameskibler]

ok this one is with servos and ubec on:


and this is with everything on:

[Flyn]

I think you might want to move your vtx to the wingtip bud, looks a bit close is it under 1ft from the VRX? This will cause issues.

Also would be good to check graph with motor running at flight speed as rx is damn close to that too.

[Flyn]

Cool, do you have a graph with everything off - just with the rx on USB?

[Flyn]

Just try with your the plug out of your vtx then plug it in to see if it's that adding the noise

[Flyn]

The plane is a little noisy but not too bad. What's the hump at 459? That's the one you need to reduce.

Would be good to reduce the hump at 452-453 too.