Screen interference - grounding?

**dmurray14** · 05-20-2005, 09:07 AM

I'm getting some annoying interference on my Xenarc in dash. I think it's picking up some interference on the 20' or so run to the trunk. I get lines on the screen that increase in frequency with the engine, leading me to believe that it's not adequately grounded. Is there an easy way to ground the VGA cable? I was thinking about hooking up a wire from the shielding on the VGA cable to ground on both ends - would that help? Should I also be hooking the computer case up to the car's ground? Any ideas? I'm also getting the all-to-familiar alternator whine when no music's on, but that's not as annoying as the screen interference.

Thanks,
Dan

**Gobby** · 05-20-2005, 09:34 AM

I also get this but don't know how to sort it, my noise also effects the speakers and the screen generates noise from the backlight inverter.

**neon_eddy** · 05-20-2005, 09:49 AM

get heavy gauge wire or use lots of smaller guager wire to ground your case, and screen ..

GROUNDING GROUNDING GROUNDING! I also got a aftermarket VGA cable the stock ones have little grounds, and little shielding.

mine is EMI free right now.. but who knows I'll mess something up

**dmurray14** · 05-20-2005, 12:01 PM

Will do. Case is currently ungrounded. Should I try grounding the VGA cable shielding as well?

Thanks,
Dan

**neon_eddy** · 05-20-2005, 12:44 PM

yes.. ground everything and anything until the picture cleans up .. think of electricity like water.. it needs to flow through least resistance. right now it's flowing easier through your LCD than to the normal ground..

and try connecting and disconnecting other things to see where the noise os coming from..

mine happened to be the case .. and it needs to be a solid ground.. I had to screw it in tight before it cleaned up..

**kmcniece** · 05-20-2005, 12:46 PM

Originally Posted by neon_eddy

yes.. ground everything and anything until the picture cleans up .. think of electricity like water.. it needs to flow through least resistance. right now it's flowing easier through your LCD than to the normal ground..

and try connecting and disconnecting other things to see where the noise os coming from..

mine happened to be the case .. and it needs to be a solid ground.. I had to screw it in tight before it cleaned up..

Best description of grounding problems ever........

**jeeve76** · 05-25-2005, 11:21 PM

I have my Lilliput screen getting power off the power supply, I have 12v and the ground ran from the power supply to the lcd. Should I just cut the ground on the lcd and ground it to the chassis of the car?