Thread Tools
Old Sep 08, 2011, 08:41 PM
htran is offline
Find More Posts by htran
Registered User
Discussion

Diagonal lines in the video


I'm getting diagonal lines in the video, even with the RX/Motor not connected.

The video system is powered by a separate 3S battery pack with a LC filter. The setup is

Battery -> Fy-AP117 OSD -> BevRC WDR700 camera -> Fy-Ap117 OSD -> Immersion RC 5.8 TX

All wires are twisted except the wires from the camera to the OSD but that was the same with the old camera

This didn't happen with the DX201 camera, is there a way of getting rid of the noise without replacing the camera?

http://www.youtube.com/watch?v=zDa3vMTukmU
Sign up now
to remove ads between posts
Old Sep 08, 2011, 09:32 PM
Toysrme is offline
Find More Posts by Toysrme
Registered User
Toysrme's Avatar
ground loop?
Old Sep 08, 2011, 10:54 PM
Hugeone is offline
Find More Posts by Hugeone
Registered User
Hugeone's Avatar
Counting the lines and multiply by 15750, you'll have the beat freq. of the interfering noise.
Look like it's the 400-500khz range. Might be a defective on board step-down of the camera.

-Hugo
Old Sep 09, 2011, 01:55 AM
Toysrme is offline
Find More Posts by Toysrme
Registered User
Toysrme's Avatar
huge is a beast
Old Sep 09, 2011, 06:17 PM
Devonboy is offline
Find More Posts by Devonboy
Registered User
I'm going to suggest you power the VTx at 2S (tap the balance lead for 7.4v).

Any improvement?

Nigel.
Old Sep 09, 2011, 10:10 PM
RolandS888 is offline
Find More Posts by RolandS888
Outta Sight
I think Devon is right.
I have seen this coming from the IRC Vtx.
To experiment, try powering the VTx with a separate 2S LiPo, it should clear up.
If the Vtx is connected to the camera with the same power supply this will happen every time.
Goodluck. Let us know how you go.
Old Sep 09, 2011, 10:29 PM
Hugeone is offline
Find More Posts by Hugeone
Registered User
Hugeone's Avatar
I saw it on the foxtech 5.8 Vtx, the onboard 3.3V step-down produced similar lines. Bad filtering design or something, I have two and both does this.

However, the IRC designer brag a lot about his attention to details so I doubt it could be the Vtx. Anyway, those lines are from switching power supply somewhere in your setup.
There's one in your camera and one in the Vtx.

Tip: Touch and hold the Vtx, look for change in the lines, do the same with other thing you may suspect.

-Hugo
Old Sep 10, 2011, 04:19 AM
Devonboy is offline
Find More Posts by Devonboy
Registered User
I have this same 'herringbone lines' issue with onboard switching regs on another Immersion VTx and another well known VTx (not a Chinese product and the supplier is also well respected).

I made a test powering from a variable voltage linear power supply and you can see the differences here (click through to watch it directly on Vimeo in a larger screen)...

5.8GHz VTx problem (0 min 59 sec)



My gut feel is still with filtering as I had a similar problem on a homebrewed 5.8GHz setup...

Homebrewed 5.8GHz FPV rig - First light. (2 min 23 sec)



Improved filtering resolved it...

5.8GHz with improved video (1 min 2 sec)


Nigel.
Last edited by Devonboy; Sep 10, 2011 at 08:02 AM.
Old Dec 13, 2013, 12:46 PM
Zangetsu57 is offline
Find More Posts by Zangetsu57
Registered User
I know I'm digging this up, but I have the same exact problem with my ImmersionRC 600mW 5.8 GHz Tx. Thanks for posting the video with the varying DC PSU, Nigel. I'll try powering my VTX off 2S. Would there be any issues in throwing my lipos off balance if I tap 7.4V off the balance lead of my 3S packs? I'd prefer to not add the weight of a second battery.
Old Dec 13, 2013, 02:22 PM
Devonboy is offline
Find More Posts by Devonboy
Registered User
I haven't had any issues with tapping the main LiPo pack for lower voltages and low power consumption devices.

Nigel.
Old Feb 17, 2014, 12:46 AM
Zangetsu57 is offline
Find More Posts by Zangetsu57
Registered User
It is inconvenient to need to tap off the lipo balance lead. Has anyone tried adding more filtration to the TX PCB after the switching regulator (such as a larger inductor)?


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion Getting horizontal lines in video with a separate battery OrlandoP FPV Talk 7 Aug 14, 2011 10:15 PM
Discussion Lines in video yellowcolorado FPV Talk 20 Dec 31, 2009 03:39 AM
Help! Lines in video when motor running...help please. cadders FPV Talk 17 Dec 14, 2009 10:08 PM
Discussion How to get rid of lines in video EyeFlyPlanes FPV Talk 10 Jul 02, 2009 04:34 AM
Discussion Image problem - diagonal lines DerKorb FPV Talk 6 May 01, 2008 04:41 PM