Thread: Outside Antenna
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Old March 5th 06, 09:57 PM posted to rec.radio.shortwave
Bob Miller
 
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Default Outside Antenna

On Sun, 05 Mar 2006 13:25:52 GMT, "Rikk"
wrote:

Hi
I am wondering if I have my longwire set correctly, maybe you could advise
please.
At the moment I have a sloping long-wire of about 50 foot, going from the
top of a mast on my house about 35 foot tall to the top of a washing line
post about 12 foot tall. I have connected the lonwire to my radio by means
of CB-coax, what I have done is to attach the centre core of the coax to the
longwire and I have cut the outer sheath on the coax near to the ground and
connected an earhtwire that is soldered to a cold water main supply pipe as
an earth.
Only the centre wire on the coax is connected to the actual longwire.

Is there a way I could do better.

I am thinking about getting an active antenna, the Sony AN-1

Would this work better for me or is there a better alternative available.
I am running an Icom R72
thanks
Rikk


If you don't have too much man-made noise inside your house, you might
consider bringing the random wire all the way to the 500-ohm terminal
on the back of your receiver, and run your ground wire from the
terminal next to it to your cold water pipe. This gets rid of the
mismatch between your high impedance antenna and low impedance coax,
and you don't need the balun at all, which is fine, because the balun
only provides an approximate impedance transformation.

Another alternative would be to bring the long wire into your house,
and attach it to an inexpensive random wire antenna tuner, such as an
MFJ 16010, about $49 US. Then run a short length of coax from the
tuner to your radio's 50-ohm input. As you go to each new frequency,
peak the knobs for maximum signal strength.

Yet another alternative, keep your current antenna; add the balun to
it or whatever. But put up a 2nd antenna, perhaps aimed in a different
direction, and run it to your high impedance terminal. Switch between
the two antennas for best reception on a given signal. You could do
some interesting A-B comparisons on antennas.

Bob
k5qwg