I need a counterpoise (maybe I'm wrong). It will be short and T shaped to minimize radiation, as shown in Moxon's book (that's my bible). In a previous location I had successfully tuned an upstairs ground lead for top band : it was very pleasant to see the antenna current increase (with a home made RF-peg) as I tuned out the gnd wire reactance. For now I have not enough spare time to DIY (although I assembled the K2,hi). Had a think about Ten-Tec artificial ground, but it's difficult to find here, and now I fully appreciate the auto gearbox of the K2. Then T1 appears : if it searchs for a current maximum, that should work, why not ?
So, is it possible to use it as a counterpoise-only tuner ? (KAT2 does the rest) Regards to all es 72 de F5LCI in the french countryside, 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: Elecraft@mailman.qth.net 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.htm Elecraft web page: http://www.elecraft.com
