lilliput whine

**viktorcarpc** · 06-30-2007, 07:58 PM

I've had a pc set up in my car for a long time and I've been pretty happy with it. There have been a few things though that at first were anoying, but then I got used to them and didn't bother me that much. Now that I'm on vacation and have more time I've decided to fix them.
The number one most anoying thing that I've had is some sort of a whine that comes through the speakers everytime the car is on. The noise increases in pitch as the revs of the engine increase. It actualy sounds kind of like a supercharger except that it's anoying. The noise doesn't increase if you turn up the volume. (btw I have a lilli 7" in dash with an internal amplifier). Another thing is that when I turn on my A/C or rear defroster or whatever other electric device, the noise increases a little bit. I've talked to a lot of people about this problem and they're not sure what it is. They tell me that all the alternator whines that they have heard don't change in pitch.
The second most anoying thing is that the screen flickers and there are lines going up and down on it. The flickering increases as the engine speed increases, therefore it disapears when the engine spins fast enough.

Any suggestions?

thanks

**Snortonnorton** · 07-01-2007, 12:02 AM

i've always worried about this to since I'm about to do my first install. I love seeing how so many people post pictures of pretty clear screens but I wonder how can they not get static from power revs in the system.

hopefully, the experts here will chime in

**slickdeville** · 07-01-2007, 08:09 AM

The whine sound in systems is usually cause by ground loop.Try a search on ground loop...loads of info.

**2k1Toaster** · 07-01-2007, 10:49 AM

Well for the audio, yes I think it could be a ground loop as well. Before you start ripping out wires, and rerouting them, go to your nearest radioshack, and buy a ground loop isolator. Try it, if it works, you know what the problem is. If it still sounds ok to you, then keep it. If you dont like the new sound, then return it. Radioshack is a 30day no questions asked return policy. So good for this sort of thing. And dont worry about the morality. I used to work for them, you have nothing to feel bad about, I promise.

As for the video, are the lines wavy as in you can see the image underneath the wave, as it moves up and down, or are they black wavy lines with no visible image under them?

I think you have option 1, but I want to make sure. If option 1, then it too is a power problem. Either a) you are powering your screen off of unregulated 12v intentionally or unintentionally or b) power cable too close to your vga cable.

for (a), if you are using your egg that came with it, it could be fried and passing unregulated voltage. check that with a multimeter. If that checks out, then your only option is to re-route the vga cable. They make video isolators (like the radioshack ones, but for video instead of audio) but they are pricy, when a simple re-route will fix. No place I know of can you buy one and return it later.

And it is possible to get a clear image on your screen. I have seen it in many people's cars. I myself use the unregulated voltage to my screen because it was cheap, and is already broken (no 800x600), so when it dies, I get a new one, yippee!

But it has been going strong for a year now unregulated, but I get the wavy lines, and the happy thoughts of knowing it may just burn out and die at any second. It is brighter though

.

**viktorcarpc** · 07-01-2007, 11:54 PM

Yea I think I will try the ground loop isolator, but I'm not sure I have a ground problem because I think I have a pretty good ground that is screwed right on the chassis of the car. As for the video problem, it's lines that go up and down and you can still see the image behind them. Kind of looks like when you look at a TV on a TV but not as anoying. I will try setting the monitor to 75hz and see what happens.

Thanks

**rationalpi** · 07-02-2007, 12:02 AM

have you tried putting a better ground on your car. In the engen block take some thick wire and run it to the black battery terminal. Have the wire start in different locations so the resistnce to get the battery is much less.

Doing that helped me a lot.

**viktorcarpc** · 07-02-2007, 09:20 PM

No, unfotunately I haven't tried a better ground, but I have tried other grounds that didn't work as well as this one. I wanted to ground it directly to the negative terminal on the battery but I heard or read somewhere that it wasn't safe. (if I'm wrong please tell me

) I should also point out that since I blew multiple fuses using the power from the old connector I decided to power the lilli directly from the battery and used fuses to make sure I don't mess it up.