noise in audio

**Harvester** · 10-13-1999, 11:11 PM

i bet this question has been asked a billion times by now, but i still need help. i use an inverter and the machine has onboard sound. the buzzing is horrible with just a direct wire to the 1/8" input on my head unit. if i use one of those ground loop isolators from radio shack, the buzzing is muted a bit, but still pretty bad. i tried "grounding" the machine, but i couldn't get it to work/figure out where to wire it. would getting a battery lead adapter instead of using the cigarette lighter help? any suggestions would be great

**alecl** · 10-13-1999, 11:33 PM

Plug a $2 surge protector (power strip) into your inverter and the power supply into that. It acts as a filter. I had the exact same problem and I used the ground loop isolator too. Ground loop isolator + surge protector is near perfect

**Harvester** · 10-13-1999, 11:57 PM

ok, i tried that, and if anything it made it worse. i dunno, maybe i'm just really picky but the buzzing just really ****es me off.

**lifter** · 10-14-1999, 01:33 AM

Ground the chassis of the computer to the chassis of the car. Meaning, make sure it (or a wire leading to it) connects to the frame, or the negative terminal of the battery.

**mda** · 10-14-1999, 10:31 AM

You need a wire, bolted to the power supply case, then bolted to the metal case (if you have one or bolted to an earth point (one of the mounting holes) on the mobo, then the negative battery terminal (provided your car is -ve earth). That should fix it.
Make sure all the connections are good and that you use a single piece of decent cable.

Lee!

**alecl** · 10-15-1999, 12:17 AM

Hmmm.. I'm real picky about buzzing too, but it went away on my system with the strip. If you really want to reduce noise, use a DC->DC converter and you'll eliminate the 60khz (Hz?) whine. I'm in the process of replacing my inverter setup with a DC->DC, but it's being delayed by my classes and job taking up most of my time

**ZyKlon X** · 10-15-1999, 09:20 AM

Harvester,
For Grounding

If the Pc is in the front of the Car, try to look for an bolt for the seat. They are usally covered up by some plastic. If it still dosnt work then stick it to the Battery of the car. Also try to get a Ground loop isolator, Radioshack sells them. I live in Kuwait and they sell them here, so you should be able to find it there.