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I have my PC system in, up, and running but.....the audio and video quality is suffering. Let me first give a quick description of the system. I have a set of RCA's, s-video, 2 usb and 1 firewire running down the passenger side together to the rear floor compartment. There is a 12ga and a 16 gauge power running down the driver side. The video and audio all run to the avelectronic box under the passenger seat. I have a dvd in the center console also hooked to the ave box. The dvd, ave box and two P.I.E. amps are all grounded at a bolt holding the NAV unit to the floor. The PC is grounded back in the rear floor compartment. I have two case fans also wired to the this ground and the incoming power wire.

So I have this bad engine whine after I get everything hooked up. So after a trip to radioshack for a noise suppressor I find a ground loop isolator and see that is what I probably need since I have two seperate ground points. Well that helped a lot but I still have some whine and the audio quality just isn't what it should be. It sounds kind of distorted and makes some craking noises. The video is also not great. The picture is not real stable. It has some flickering going. At first I thought maybe it was just the nature of the PC but I tested it out by hooking it to my 32" home tv and stereo and all is good there so there is definately an issue with the car wiring. I ran a seperate rca cable instead of s-video in the car and same thing. I don't have any of these problems with the audio/video coming from the DVD player, so I am deducing the issue is before the signals get to the ave swither box from the pc vs. on the output side.

I'm guessing that there is a ground problem with not having a ground tied together with all the components. So how should I ground eveything correctly? Should I run a 12ga wire connecting the ground point in front to the one in the rear? or do I need to tie everything to one ground point? Right now I have everything crimped because I can't for the life of me get solder to stick to the wires. I think the crimps are tight though. The other thing I'm going to change is to hook the fans to their own ground. I bought decent AV cables that were shielded, not the expensive stuff but they weren't exactly cheap either.

Anyone have any suggestions or recommendations on the proper way to handle the wiring? thanks.
 

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Discussion Starter #2
It was a bad ground, I choose a better ground point for the rear and everything is golden now:). I checked the ohms at the battery and the two points that I am grounding at and they are the same now.
 

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Hey Lonnie,

Glad you got it lined out. My audio guy told me to make sure your ground points are no longer than 18" each for best results.

Good job on the carputer. I'd love to do the same thing- I'd have to install a screen in my dash though. I'm lazy (and broke) :)
 

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Just out of curiosity, where exactly did you ground at? Reason why I am asking is that I had the same problem. I ended up using the bolt for the LATCH system in the very back of the compartment, by the hatch.

Also, how did you measure the ground again?
 

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TooTall said:
Just out of curiosity, where exactly did you ground at? Reason why I am asking is that I had the same problem. I ended up using the bolt for the LATCH system in the very back of the compartment, by the hatch.

Also, how did you measure the ground again?
I grounded to one of the seatbelt anchors. I used an ohm meter and hooked a long piece of wire to the negative battery terminal and then just touched my ground point with one probe and the other probe to the wire attached to the battery. At both points I had the same reading so I figured that was a good thing. My whine started to come back which I bet is the ground again. I need to get a good connector and sand down to metal (plus shorten my ground wire which is 12ga. about 4' long that came in a amp kit from walmart)
 

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Always sand your ground points down to bare metal. The frame is the best ground. ;)
 

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If after you do all this you still have some noise you may have to spring for some new RCA and S-video cables. You can get some of the double shielded ones, and ground the outer shield on one end only, not both ends. This will help eliminate the recirculating ground currents.
 

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Discussion Starter #9
ftnssn said:
Your ground point shouldn't really be any more than 18 inches from your power source.
I'm pulling straight from the battery, you aren't saying I should be grounding in the engine compartment are you? Just 18" from the unit I'm trying to ground correct?
 
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