Wayne N6KR wrote: "...what you described won't work very well, because both wires need to be about 33 feet long at this frequency. By cutting one 33-foot piece of wire in half, you've made a 20-meter antenna :)"
-------------------- A modeling program like EZNEC predicts that a 33-foot center fed wire will show a gain of about 6.9 dbi on 7 MHz and about 7.1 dBi on 14 MHz. That's essentially no difference at all. That's at a height of about 30 feet where the antenna's main lobe is straight up for short skip work on 40 and down around 30 degrees on 20 - useful for DX ing. The difference remains on the order of 0.1 or 0.2 db between 40 and 20 all they way down to under 15 feet, where ground absorption will start to show a significant loss on 40 due to the low height of the antenna. That miniscule difference in performance between a half-size and full size doublet agrees with what many handbooks, including the ARRL handbook, has claimed for many years. Of course, that assumes no difference in matching network losses, which I'd not expect a KX1 user to see using such an antenna without a feed line. (Of course, if a coaxial feeder is used, then some means to holding down the SWR on the feedline is very important to avoid losses there.) I was concerned that the tuner in the KX1 wouldn't be able to handle the high impedance of a 1/2 wave (33 ft) wire on 20 meters. 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
