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View Full Version : Engine noise/ whine in my audio


Anduinlight
03-30-2005, 08:02 PM
So I am currently in the process of installing a "Carputer" into my car for doing DSM link eventually and right now is doing GPS and Audio.

now In the process of hooking it all up I've been getting alot of engin whine on the monitor (screen) and in the audio. I have done some trouble shooting myself but I can't seem to get rid of it. So hear is all the info, maybe another one of you car audio guys or lightning might be able to help me out

-monitor is a touchsceen USB/VGA hookups, noise in in bars across the sceen which niether speed up or slow down moving up and down the screen when my RPM are up or down
- I have a pioneer deck with a CDRB-20 (Add on auxilliry input to the radio) which basically has RCA hookups on one side and Din (serial) cable on the other side. I know the RCAs i'm using are fairly shielded to noise, and the CDRB-20 is a pioneer made piece that I would assume block most noise. The noise comes through speakers as a high pitched "whine" that also doesn't lower or raise in pitch depending on RPMs.
- I have a 350 Watt power supply that is giving the "carputer" its power. This power supply is fan/heatsinnk cooled. (the fan is the only thing I can think of causing the noise) the powere inverter is powered stright from the battery via 8 guage power and grounded about 3 feet away from where the inverter rests (grounded witha 4 guage wire on the main dash support beam behind the radio)
-the computer itself in plugged into the inverter and has a filter/transformer/voltage dropper that I would assume woudll block noise
-also the monitor is a 12v powered monitor that is harwired into (same as the inverter (same power source) the car. It also has a filter to maintain its 12 volts
- the only other thing is there is a din cable for my XM radio running to the back of that car, which also has power running with it (for the XM) that may be picking up noise.

I've tried alot of thing to get rid of this noise but it will not go away, and it doesn't funtion like normal car audio/video noise.
so if you guys have any idea?
let me know

BTW my car is a 92 Talon AWD
Regular battery, only 4 monthes old
new alternator, also 4 monthes old

Anduinlight
03-30-2005, 09:26 PM
/ bump

Jakey
03-30-2005, 11:32 PM
Have you checked the grounds for your car in general?

LightningGSX
03-31-2005, 01:32 AM
If I had to guess, I would say its the inverter.They are usually noisy pieces of shit.Also, does your VGA cable have a ferrite filters(usually large bumps on the cable near the plugs)? Is the inverter case mounted to metal?

Anduinlight
03-31-2005, 11:21 AM
If I had to guess, I would say its the inverter.They are usually noisy pieces of shit.Also, does your VGA cable have a ferrite filters(usually large bumps on the cable near the plugs)? Is the inverter case mounted to metal?
the case for the inverter is not mounted to metal, it is above the carpet under pass seat. Yes the VGA cable has a little knob a few inches from where it plugs in.
as far as checking the grounds in my car, my whole car chassis reads continus with ground post on the battery (i think that means good ground ;) but other check of the grounds i'm not sure how to do.
I will try mounting the chassis of the inverter to somthing metal see if that clears it up

x-pride
03-31-2005, 11:36 AM
Are you getting the wine in your audio system with this set up? What I mean is are you getting noise when you listen to your radio etc. If so I would recommend to disconnect one piece of equipment at a time to see what the cause is. Sounds to me like an alternater wine coming in from your RCA or Power wire. Are these two wires run together?

Anduinlight
03-31-2005, 12:43 PM
Are you getting the wine in your audio system with this set up? What I mean is are you getting noise when you listen to your radio etc. If so I would recommend to disconnect one piece of equipment at a time to see what the cause is. Sounds to me like an alternater wine coming in from your RCA or Power wire. Are these two wires run together?


the RCAs and power wire are far apart (other sides of car) and it only is audiable when i'm using the aux.

LightningGSX
03-31-2005, 05:48 PM
If the noise doesn't change with engine RPM, its not engine noise.

Take a multimeter and check for continuity between the inverters' metal case and the inverter ground.

Anduinlight
03-31-2005, 08:13 PM
alrighty