e9stibi

I hooked up a Dell PDA to my CDR 220 via Becker aux input cable and experience wining noise that follows the engine revs. This happens only when I supply the PDA with 12V power from the car. On battery, it is silent. it appears that my power supply is not "clean".

What is the best way from your experience to supply an aux input device with clean 12 V?

Thanks,
Erik

Kika

Ground loop most likely, get a ground loop isolater. David NAvone sells them on his website, or try an electronics store, like radio shack, Fry's etc...

Stealth 993

Try a better ground for the charger.

e9stibi

Stealth - What is "a better gound"? Would you take the ground that connects to the radio plug?

Erik

Southampton76

Try and ground to metal and not an existing ground, might help. Ground fault isolators are cheap and will remove a lot of noise. But, its a ground that is causing the whine. Does it get worse when you rev the engine?

e9stibi

yes, it gets worse with engine revs.

Southampton76

Bad ground. Try a ground fault isolator, can get them from radio shack. You can also buy a suppressor that mounts on the alternator mounting bracket, that will suppress noise from the alternator and cut out the whine as well.

Check the grounds first, make sure its metal to metal and if you can, put it on a separate earthing point.

I have this very slight whine on my Ipod even with a GFI.

Stealth 993

You can try the radio ground, or ground it to the radio body it's self.
Or just find another metal ground around the area, it might take a few tries to get the right one.

c993k

Hi Eric
Here's a good description of the problem http://www.carstereo.com/help/Articles.cfm?id=71
Chris