Another fuzzy screen question (I have searched)

braidy · 01-21-2008, 11:13 PM

Hey guys.

As I have said, my Lilliput 7" is fuzzy. Running my laptop on batteries, I get no fuzziness whatsoever. It's only when I give it power from my cigarette lighter adapter ( http://cgi.ebay.com.au/ws/eBayISAPI....B:EOIBSA:AU:11 ) that I get interference. I have added an earth from the VGA plug to the car's chassis, which has helped with the flickering of the screen, but the fuzziness is still there.

I have tried the barrel connector. Screen is running at 800x600.

Help!

Cheers,
Braiden.

2k1Toaster · 01-21-2008, 11:20 PM

its very simple. You installed it through the cig lighter like everyone says not to do including myself. You are pulling too much juice. Run a dedicated wire for the laptop adapter and watch it go away.

braidy · 01-21-2008, 11:31 PM

Quote: Originally Posted by 2k1Toaster

its very simple. You installed it through the cig lighter like everyone says not to do including myself. You are pulling too much juice. Run a dedicated wire for the laptop adapter and watch it go away.

I will try that. Any other ideas?

2k1Toaster · 01-22-2008, 12:15 AM

Quote: Originally Posted by braidy

I will try that. Any other ideas?

Is the VGA cable for the screen running really close the cig lighter power cables? If nothing is being powered, no interference, but if something is pulling juice, it is making itself a e. field, and causing interferance. It could be a bit of both things here. Something to try if you can is to get the VGA cable from the screen and run it out of the dash temporarily for testing through the dash hole to the laptop away from the power lines of the laptop with it plugged in. If the interferance goes away, then a simple VGA cable re-route will work. But if you power it from a dedicated line, you should also make sure the VGA cable is not routed by the line.

braidy · 01-22-2008, 06:48 AM

Quote: Originally Posted by 2k1Toaster

Is the VGA cable for the screen running really close the cig lighter power cables? If nothing is being powered, no interference, but if something is pulling juice, it is making itself a e. field, and causing interferance. It could be a bit of both things here. Something to try if you can is to get the VGA cable from the screen and run it out of the dash temporarily for testing through the dash hole to the laptop away from the power lines of the laptop with it plugged in. If the interferance goes away, then a simple VGA cable re-route will work. But if you power it from a dedicated line, you should also make sure the VGA cable is not routed by the line.

Gave it a dedicated line, didn't fix it. In fact, it made it worse. Will try a re-route of VGA tomorrow. Really starting to **** me off though. Any other ideas?

2k1Toaster · 01-22-2008, 09:50 AM

Quote: Originally Posted by braidy

Gave it a dedicated line, didn't fix it. In fact, it made it worse. Will try a re-route of VGA tomorrow. Really starting to **** me off though. Any other ideas?

And ground? you did put just as thick of a ground running to a nice unpainted bolt/ factory grounding spot correct?

braidy · 01-22-2008, 07:37 PM

Quote: Originally Posted by 2k1Toaster

And ground? you did put just as thick of a ground running to a nice unpainted bolt/ factory grounding spot correct?

Yes, I did that. I know a fair bit about car electrics. I tried unplugging the power source last night to see if that improved it, and it didn't so I am guessing it's interference somewhere along the line. I'll play around with it today and see how I go.

Also, will the refresh rate of the screen have something to do with it? It's running at 800x600 @ 60hz at the moment. Should I boost it to 75hz?

braidy · 01-22-2008, 10:54 PM

Fixed it. I stupidly overlooked how tight I made the barrel connector. That fixed it pretty good.

braidy · 01-24-2008, 09:06 AM

Wait, the noise is back. Fuzziness is fixed, now I am getting flickering in the screen. However, it only happens after about 2 minutes of driving. WTF?

hithere · 01-24-2008, 09:10 AM

Auto AC/heater fan coming on after two minutes of driving? What about cooling on the PC? Bad filter caps in a given DC power supply can cause AC to be present where it shouldn't. Source of interference may not be the actual problem. Re-check all grounds, re-route VGA.

braidy · 01-24-2008, 09:19 AM

No engine fans or AC or anything coming on. Grounds are fine, VGA route is fine. Would grounding the actual laptop case help?

braidy · 01-24-2008, 09:19 AM

Oh, and if it helps, there's noise in the audio too. A constant lowish pitch whine.

brucedog · 01-24-2008, 09:30 PM

Check the VGA connector right at the monitor case. I remove my monitor when in not so good areas; sometimes when I plug it in, there's screen noise due to needs to be plugged in more securely.

The provided cig liter plug adaptor induced noise into my car's wirng, that came thruaudio system some. Re-routing 12volt supply helped. looks crappy stickin' out of the lighter socket, anyway...