Odd alternator noise problem, only Lilliput.

shotgunefx · 04-02-2007, 10:53 AM

Have an issue with alternator noise that's driving me batty and was wondering if anyone can give me some suggestions.

I'm getting a lot of alternator noise on my lilliput (slight strobing that increases/decreases with rpm), and only on my lilliput but not other devices that are powered by the same regulator.

The lilliput is being powered by a LD108412v regulator I built, also I have a front mounted cam and the line driver for my amp are being powered by the same regulator. The cam has no noise on the picture, there is no whine getting injected into the line driver, just the lilliput.

Everything in the car (laptop, lcd, linedriver, Quad video processor, cameras) is grounded to one point.

Could it be the VGA cable? I added some extra ferrites to it but to no avail.

2k1Toaster · 04-02-2007, 12:13 PM

I can almost guarentee that it is the VGA cable. I have no solution though other than move the cable, or buy some really expensive shielded cables. Test it out with just running the cables over your seat to your dash instead of where it is probably hidden now. See if that helps. If it does, then you just need to move it. By your audio cables is a good spot unless you compete.

shotgunefx · 04-02-2007, 12:46 PM

Quote: Originally Posted by 2k1Toaster

I can almost guarentee that it is the VGA cable. I have no solution though other than move the cable, or buy some really expensive shielded cables. Test it out with just running the cables over your seat to your dash instead of where it is probably hidden now. See if that helps. If it does, then you just need to move it. By your audio cables is a good spot unless you compete.

Have a feeling you're right. All of my cables are run through the center console down into a luckily empty factory wiring channel in the floor to the trunk.

Options for relocating it are limited (the other channel is packed with the factory harness).

I'll have to dig around for some of my shorter 1/2" vga cables I have laying around and just daisy chain them and see if that works better.

In the meanwhile, I'll see if I use my s-video out if I have the same problem. Pretty sure I won't as the video going to the lilli doesn't. (It runs from the camera in front, through the trunk, to the quad processer and pc, then way back out to the lilli in front).

shotgunefx · 04-03-2007, 08:08 AM

Quote: Originally Posted by 2k1Toaster

I can almost guarentee that it is the VGA cable. I have no solution though other than move the cable, or buy some really expensive shielded cables. Test it out with just running the cables over your seat to your dash instead of where it is probably hidden now. See if that helps. If it does, then you just need to move it. By your audio cables is a good spot unless you compete.

Hmmm. Replaced it with this massive one I had from way back, triple shielded and about a half inch thick (used it for my old hi res 19" crt back in the day).

Much better, but still there slightly. Wonder if it's the stupid lilli din.