> Forget this silly stuff with the 300 ohm line and the coax. Simply
> run a wire from one end of the antenna to the center conductor of
> a coax input of your tuner. Then connect the chassis of both the
> tuner and the rig to the counterpoise.
Some tuners won't tune a 1/2 wave wire, since the impedance is
800 to 3000 ohms. There is an easy fix for this; put a doorknob
capacitor of 50 to 200 pF from antenna to counterpoise. Now
your tuner will probably be happy, because the impedance is
now in the 100's of ohms.
You can even put the capacitor right at the end of the wire
and drop the counterpoise from that point (all outside).
Then connect the tuner to the door knob with coax.
A low dipole such as you have is not a DX antenna, but is
wonderful on NVIS within a couple of hundred miles. Hopefully,
such local signals are strong enough to get through the RFI.
You can also use your wire on 40 meters as a hi-Z full wave. I have
done this before successfully. On 30 meters, the wire will
no longer be a high impedance but your counterpoise only needs
to be 25 feet on that band to allow you to drive a low impedance.
Because it is low impedance on 30 meters, you can get away with
leaving the doorknob in place. Again, this worked for me.
Rick N6RK
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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