Many thanks for the answer.
I thought that it tuned for max current...
As I already have a current indicator, I will try my home-made QRO
matchbox in series with the counterpoise lead, then measure inductance
with my Autek RF-analyst, to copy it into a small device, maybe biband
(160/80) if I manage to do it.
Ok for my QTH, we have many sorts of both : I prefer those made from crude
milk (FDA critical...), AND you forgot the third element : beverages (not
the antennas).
72,
Ron wrote :
Excellent idea, IF the T1 actually tuned for maximum current.
Unfortunately,
it does not. It uses a bridge circuit to provide a 50-ohm non-reactive load
to the transmitter. While that might be better than a short, untuned
counterpoise, it is far from ideal.
What I have done in your situation is to use a simple coil. A short
counterpoise will be capacitive, so what you need is an inductance to bring
it to resonance. If you are using a barefoot K2, a small inductor tapped
every turn should be FB. I once made one wound on a cardboard tube that
once
held a roll of paper towels. What Ten Tec does is add a variable cap in
series with the coil to allow for small adjustments in between the taps,
and
to provide a way to tune out inductive reactance in a counterpoise when it
is electrically longer than 1/4 wave.
You need a current indicator. That's easy. A small flashlight bulb in
series
with the counterpoise. Short it out after finding the tap with the greatest
current.
Your QTH makes me hungry for some French Bread and a wedge of Brie.
Ron AC7AC
_______________________________________________
Elecraft mailing list
Post to:
[hidden email]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft
Help:
http://mailman.qth.net/subscribers.htmElecraft web page:
http://www.elecraft.com
Locked
