MOBILE NOISE/STATIC

Just what it says -- this is the place for any discussions not related to Buying, Selling and Trading ham gear. The discussion must be related to Ham Radio.
Post Reply
jason
Posts: 1
Joined: Mon Aug 02, 2010 10:25 pm

MOBILE NOISE/STATIC

Post by jason »

hello, i recently installed a mobile and im having terrible static and engine reving coming across the radio. i would appreciate any ideas to help correct this, thanks jason
N9LCD
Posts: 330
Joined: Sat Jul 01, 2006 8:32 pm

Post by N9LCD »

Jason:

Does your "engine revving" increase in pitch as the speed of your engine increases? If it does, you have ":alternator whine", AC current from the alternator that bypasses the your car's filtering network and gets into your radio. no vehicle and no rig is absolutely immune; I've even heard alternator whine on fire and police mobile transmissions.

SOLUTION: An alternator filter. The capacity of the filter, in amps, will depend on you car's electrical system and the current your mobile rig draws. I can't recommend a particular filter because I don't know what's available in your area.

Static is a different problem. It would help to know what band(s) you're operating on and your car and what kind of ignition system it has. Certain types of electric motors generate a lot of "hash" that can get into even VHF FM receivers by conduction; I've had that problem at home on and above 2 meters.

N9LCD
KB3LMV
Posts: 45
Joined: Sun May 31, 2009 2:40 am
Location: Melrose Fl.

Whine & noise

Post by KB3LMV »

Hi
Your whinning sounds like AC ripple from the alternator.try disconnecting the output lead & firing up.If whine goes away,then install a PIE filter in line close to alternator or a Large 20-30V Cap between output & grnd.Either one will help.
As for the static problem try a couple of bonding straps between hood and body.This problem is commom in Ford products as their hood hinges are lousy conductors.
73 & GdLk
Paul
Paul KB3LMV
Post Reply