[MOSFET]

First off, Greg knows much more about EE matters than I so I defer any and
all questions of a technical nature to him.

HOWEVER, that being said, I DO know that your car's engine (alternator,
sparg plugs, ect.and other accesories in your car) emit more EMI
(electromagnetic interference) inside your car than your typical suburban
power lines along side every residential rode. In my 25 years involved in
car audio, I have NEVER heard of problems caused by your ordinary power
cable.

True, when I have gone near LARGE CURRENT bearing cable like from a damm or
reactor to a substation I do encounter noise over my AM band. I really
don't think there is anything you can do about that as the EMI just plain
over-powers and distorts all AM signals. There's no way for your radio to
discern what's an AM signal and what's EMI on the AM band, a little like
going through an "EMI" tunnel. But those type of massive lines tend to be
few and far between

But again, I have NEVER heard of plain old suburban power cable causing EMI.
There just isn't enough juice going through those wires to create the kind
of interference your describing, unless, again, you live near VERY large
current bearing cable.

I'm curious, how did you deduce it was the power cable causing the
interference? Are you sure that's the source?

MOSFET


"GregS" wrote in message
...
In article , "Bob F"
wrote:
I recently acquired a 1994 Dodge Caravan with a pioneer supertuner AM/FM
radio.

It has bad problems on an AM staion I listen to whenever I am near
powerlines.
There is a 60 Hz hum that modulates the audio causing bad distortion. I
thought

this would be a grounding problem, and have tried adding an additional
temporary
ground at either end of the antenna cable, with no effect. Can anyone
offer any

help in solving this?



Is it hum or buzz. I'm thinking buzz.
I don't think i ever encountered this, but power lines will emit
noise. Is the noise all across the band ?
A different type of antenna may help. I'm thinking a big loop on top of
the roof.

greg