RadioBanter - View Single Post

March 29th 04, 08:56 PM

(BCcubed) wrote in message ...
Hey JBR

I do know this and have used this function. My question had to do with
damaging the radio by stringing a 75 foot square of wire 12 above the ground
and using the ext. antenna on my SAT 700 to DX without hurting the radio.

Until I can get a better radio I was hoping to find some way to modify this one
to perform better.

neil

Use two wires. One long, one short. IE: a 75 ft wire, and also a 20 ft
wire, or whatever. Experiment with the length of the short one to get
the desired signal level when listening to the powerhouses that could
overload you, or if you are suffering a problem from a powerhouse on a
different frequency. Can ever be strong MW signal related in some
cases... But if that radio has a preselector as you say, that will
help reduce out of band crud a bit..Always use that.. The long one
would be the preferred weak signal antenna unless you started
overloading. In that case, switch to the shorter one, or the whip.
This would be one method that could be used that really doesn't cost
anything except some wire. A step attenuator can be built fairly
cheaply. I prefer rotatable small loops for most MW listening. Those
can greatly help the MW performance over a long wire. There is a big
difference between the SAT 700 and a Drake R8B in nearly all aspects.
Make no mistake. But with some wire length adjustments, you could do
fairly well with what you have. There is no way you can damage the
radio from overloading it, unless maybe you had a transmitter so close
to be nearly connected to it.. :/ And many radios are protected from
that with back to back diodes, or whatever. Don't worry about that.
Whoever told you that is confused about "overloading"...It's a
performance issue, not damage. BTW, one asked about a tuner...Yes, a
tuner can help in many cases to "clean up" a radio. It won't attenuate
what you are listening to, and you could still overload on a station
you are actually tuned to, but it will reduce the level of out of
band signals. With many lower end radios, it's quite possible to see
an improvement in overall s/n ratio. Will have little if any effect on
a well designed radio that is already clean though. IE: You would
likely see less improvement when using a tuner with a R8B or other
medium quality radio, than you would a lesser radio. With an already
"bulletproof" radio, all a tuner would do is add a bit of loss...:/
MK