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Old November 4th 03, 05:37 AM
Dave VanHorn
 
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"OZARK333" wrote in message
...
I have a 2000 Ford F-150 and it seems
to be a problem with Fords. I dont know that it is a much the amp picking

up
the radio signal or the speakers/wires.
I have a Kenwood stereo, no amp, and
a 6 CD changer....gets into it as much as
the stock one did, whether it is On or Off..


The only RF problem I ever had with a ford, (since 87, when I started buying
them) was rear window wipers kicking off when I used more than 80W on VHF
with a rear mounted 5/8 wave. Never did figure that one out, had it in the
escort, and the explorer. Haven't gone QRO on the expedition yet.

"off" dosen't mean what it used to, these days. The stereo may still be
powered, but in a low power state, like your VCR is, when it is "off"..
OTOH, your RF may be rectified in the output transistors, and appearing
across the speakers, as a really crude crystal radio.
AM is probably the worst mode for this, Rectified FM ends up with very
little audio component, none in the ideal case, though in the real world,
you end up slope detecting one way or the other.

I was told to try ferrite chokes on the speaker wires....as soon as i get

the
door panels off....one of these days!


You'd want to put those ferrites as close to the radio as possible.
The speakers aren't the problem, and your RF isn't going to get into the
speakers themselves.
The trick is to keep the RF out of the stereo.

I'd also look at why you have so much RF in the passenger compartment, since
this is the real root of the problem. Sounds like you've got a lot of
current on the outside of the shield, which indicates problems on the
antenna coupling, or maybe the shield isn't attached at the radio end?