[Lowfer] Quick Antenna Question

[Lyle Koehler]

Steve, you will get all kinds of conflicting opinions on receiving antennas,
and all of them may be correct for one situation or another. Here's one set
of opinions:

It doesn't matter if the wire is insulated, because air is a pretty good
insulator anyway.

For receiving, contact with tree limbs probably doesn't hurt, except that
intermittent contact with wet branches could cause some noise. If that
appears to be a problem, use insulated wire.

I would recommend keeping the wire as far from the house and power lines as
possible, and feed whichever end is convenient with coaxial cable. The cable
impedance is not important for receiving. Use *any* kind of RF coax. One
inexpensive approach might be to get a 50 foot piece of TV coax with F
connectors on each end. Adapters are available Radio Shack to go from the F
connector to whatever connector is on the receiver. At the antenna end, you
can simply solder the antenna wire to the center conductor and leave the
shell of the connector floating. Some kind of strain relief will be
necessary to keep the solder joint from breaking, and it's a good idea to
weatherproof the open coax end with silicone. There are a lot more elegant
receiving antenna techniques using matching and isolation transformers, but
using a coax feed goes a long way. The main thing is to get the active part
of the antenna away from the horrible noise carried on electrical wiring.

On a sensitive receiver like the RX-320, 65 feet of wire should be enough
for medium and high frequency reception. I'd recommend a homebrew loop or
active whip for LF reception because they are small enough so that you can
mount them in a quiet spot in your yard (if there is such a thing as a quiet
spot in the city). By the way, a great source of wire is the local building
supply store. Probably less than 15 bucks for 500 feet of #14 insulated
building wire.

And finally, band conditions have been rather unsettled the past few days.
There have been times when I couldn't even hear the shortwave broadcasters!

Lyle, K0LR