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Old May 10th 07, 03:54 PM posted to rec.radio.amateur.antenna
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First recorded activity by RadioBanter: May 2007
Posts: 7
Default How to make an antenna for receiving (only) broadcast AM

I'm looking for plans for a simple AM antenna to connect to my stereo to
replace the little loop antenna that came with it. In the past I have
used
long wires but they are not very directional.

I have found some fairly good plans online for what looks like wire wound
around a box but all of them seem to have potentiometer in the mix
somewhere. It would be very little problem to build an aimable 18 to
even
48 inch frame.

I only have two AM stations I'd like to come in clearer (690 KHz and 1440
KHz). Would it be possible to make a 'box' with one 'tap' for 690 and
one
for 1440 then just connect one or the other the radio? How long would be
wires need to be and how would I feed it into the connections on the
radio
(coax)?



Like Richard says, it's easier to find an old cap, and build the loop
around the cap. The old analog dial stereo receivers have some of
the best variables for this purpose. Most are multi gang caps, which
often can approach 1000 pf or more if you tie all the gangs together.
This can be handy for wide freq use as you can use switches and
switch gangs in or out of the circuit to change freq coverage.
Most stereo caps also had a few small gangs with low pf values,


good stuff cut)

Almost anything is easy if you know how to do it. I was looking for
something really simple w/o any electronic parts in it. I posted several
URLs with plans for building a loop like the one you are talking about. I
naively thought I might just be able to take piece of wire that was a
fraction of the wavelength of the freq and wrap it around a frame and aim it
in the correct direction. But I didn't want to do all the work only to find
out it wouldn't work.