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Old March 27th 04, 03:08 PM
Mark S. Holden
 
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BCcubed wrote:
Hello,

I listen on a SAT 700 and want to try and catch more DX in the SW bands. I am
told that if I put too much wire on it I can damage the radio due to the fact
that it has no dynamic control. Is there a device I could buy that would allow
me to put a longwire up and then regulate how much signal the receiver is fed?
Does this even make sense?

Thanks,

neil


Here are two options.

First, a step attenuator - these will allow you to dial in various
amounts of attenuation - if you found one that ranged from 0db to 50db
you'd probably have more range than you needed. Odds are you could
leave it parked on a few db of attenuation for most of the time, and
tweak it if you were going after something particularly weak, or strong.

A dirt cheap attenuator that isn't calibrated can be made with a simple
potentiometer (like a volume control) with the antenna hooked on one
end, ground on the other, and the wiper connected to the antenna jack of
the radio. The part is likely to cost about $3 and while it's an
electronic part, you might even find it at Radio Shack.

Second - you could use a passive preselector - you'd need to adjust this
every time you tune to a new frequency.

The preselector is sort of like an attenuator with a tunable notch that
will let the frequency it's tuned to pass through with little attenuation.

It's a more flexible tool - but it's also an extra knob to twiddle when
you change the station - some people like that - others don't.