Interference on Headrest monitors

**seninha** · 12-16-2008, 03:04 AM

Since I installed this summer new headrest monitors I have a interferance problem.
As soon as the engine is running screen fills with horizontal stripes.
They go away as soon as enige stops running.

Both headrest monitors get 12V directly from the M2-ATX powersupply.

Touchscreen in the front does get his power the same way,without any problem.

Here a picture how everything is connected:

What can I do to have a clear image?

CarPC is in the trunk and cables to the battery run all the way to the front (engine bay)

**bbalazs** · 12-16-2008, 08:36 AM

Firstly you have to find it out, whether it is a signal problem or a power problem.
Concerning touchscreen: I suppose it is VGA, since HR mons are S-Video...

Run HR monitors from another battery. Is the problem persists?
If not, use ferrite core coils and filtering capacitors at power wires.
If yes, the root of the problem is in signaling. Try to cut the ground wire of the cable. Try to reduce the lenght of cable as short as possible (use a very short test cable). Use double-shielded cable.
What happenned if you use just one HR mon?
Try to provide separate THICK! power/GND cables for each HR mon.
Use 'hard' grounding, I mean use the parts of the metal chassis of your car as GND.

**seninha** · 12-16-2008, 02:33 PM

As I said,touchscreen doesnt have this problem.Only the back ones are.
I already notice that when I attache only one screen the interference is less.

I think I will first try to short both ground cable and will attache them close to the screen (seat frame work)