static/noise from motor?? galaxy DX444V

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juggernaut
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static/noise from motor?? galaxy DX444V

Post by juggernaut »

I'm running a galaxy DX44V. I've noticed alot of static noise that increases with the motor (96 f250 7.3L Diesel)
My setup: I have my coax ran from in the cab under the carpet through a drain hole plug in the driver side floor, then down the driver side frame (close to fuel lines) and then up between the cab/bed. I ran the coax through some wire loom under the carpet and where its real close to the fuel lines and changed the power wire connections - no help.
The noise doesnt bother me, but when i squelch it out i loose any incoming conversations...
Any sugestions??
Thanks in advance
Tony
galaxy dx44v in a 96 F250
kc8mob
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Post by kc8mob »

Well not to be a smart ass, but welome to the club.

You need a good EMi filter for the power wires. It's not the antenna or coax. It's noise (AC) traveling back and forth on your power cables.
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nomadradio
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Post by nomadradio »

Electric fuel pumps cause a lot of trouble like this.

Turn off the motor, and compare your noise level.

The additional noise you hear with the motor running can not be filtered inside the radio, but only at the sources where the noise originates. A pain in the neck to install, mostly. And the risks of a wiring fault in an electric fuel pump are pretty scary.

The vehicle's wiring harness acts as a transmiting antenna for every bit of RF noise generated by the brushes inside every electric motor in the truck. Sometimes moving an antenna's mounting location farther from taillight fixtures helps a little.

Some cars and trucks with electric fuel pumps will have a "dealer-only" fix available if you ask for it. Gets used for trucks they sell to business fleets that install their own radios in a truck. But you have to ask for it. And probably pay for installation, to boot.

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Rick
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Re: Static noise problems.

Post by Rick »

One of the most affective ways to stop this problem, is to use some good quality polyester block capacitor from 10nf to 47nf at 400 volts and make a loosely formed T filter across the vehicles battery, keeping all leads as short as possible and also fit two ferrite rings type T200-2 with 4 or 8 turns of you power cables round each one, one at the battery end and one at the radio end. I have used this setup on lot of vehicles over the years, on HF VHF and UHF with no problems.

Rick.
kc8mob
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Post by kc8mob »

Boy this feller named Rick is a smart one. I thought I was the only one. :D
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