David Y. wrote: > Mike and All, > > Au contraire, mon ami! Don't be too quick to dismiss using a vertical. > It's not quite as simple as throwing something over a tree, but you have to > have a tree!
Some years ago I made a 20M vertical out of a collapsible 16' (4.9M) fishing pole. I wrapped some wire around it to make a full-size 1/4w vertical element, and made a base section out of a couple of pieces of PVC pipe, making a support 6' (1.8M) high. I attached four 6' collapsible whip antennas to the bottom of the pole (when set up, this was the 6' level) for a shortened ground plane. The center conductor of the coax went to the vertical whip and the braid to a small loading coil and thence to the ground plane. I also made a choke balun for the coax. The whole thing fit in a small package about 4' (1.2M) long and could be set up almost anywhere in minutes. The pvc support had a sharp stake attached to the bottom, and the antenna was guyed by three poly ropes. With a bit more wire you could make a 40M version which would only be slightly less efficient than a full-size vertical. The method of using shortened radials with a loading coil or stub is discussed by Moxon in his book "HF Antennas for all locations" and modeling shows that the reduction in efficiency can be quite small. How did it work? Not badly, although usually not as well as a dipole at 25' (7.6M). It was very easy to put up and required no trees or other supports. It was especially good to take to the beach where it could be operated close to salt water. -- 73, Vic, K2VCO Fresno CA http://www.qsl.net/k2vco ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
