Electrical filter?

[Gimli]

I've just installed a portable MP3 player in my car and I must say it works great!

The only problem I have is that when I play it while it's charging (I used the cigarette lighter's power wire to hardwire a charging harness) I get terrible interference. I know my FM modulator already has a filter on but I don't know what kind of filter to get for my charging harness power line. When I play it on the batteries I get no interference whatsoever so I know it's coming form the charging harness.

Please help me out, maybe a link to some part that would do the trick... :(

Thanks :D

[black99gt]

Power is power.

Ground is another story. I ground my amp to a HORRIBLE spot on my car.. i get a hissing noise that changes with the amount of throttle.. Seriously!

Try another ground. I bet it will work fine then.

[Gimli]

I grounded it all to my lighter line ground, thought that would do... Should I try to ground it directly to the chassis under the console? That's the only thing that's anywhere close and I'd really like it if I didn't have to run any more wires, I'm kind of inept at wiring ;)

[black99gt]

yup try there.

Usually when you get wierd stuff like this, its most likely the ground.

Just make sure your using some GOOD wire.. size 14 guage or so will do. 12-14 guage is good really. If the ground thing doesnt work, gimme a hollar

[Hurricane]

I could be possible that your MP3 player is relying on clean power from the charging source rather than having it's own regulator. You could put a 3 terminal 12V power regulator in the power/ground line. You can get them from Active Electronics on Merivale for probably $1.00

If you want help shoot me a PM.

[Gimli]

Well, I've got a power converter from 12v to 9v 700mA so that the player gets the proper power input. I'll try to switch my ground and see if that fixes it. If it doesn't I'll drop by active when I'm back from vacation in a month :)

Thanks for the hints and I'll try to find some time this week to test out the ground thing before going away...

[Gimli]

Thanks a lot guys, the ground WAS my problem. I rewired it straight to the steel plate under the console and I my player sounds crystal-clear now.

People like you are what make this forum such a great place!

Thanks again :thumbs: