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Since no one answered your question,,
Yes it would be a problem winding a wire around the line. That is if you make very many turns of the wire. It will act like a choke to the RF and only the very bottom part of the "coil" of wire will be effective as an antenna. The rest of it will be electrically disconnected as far as the RF is concerned due to the inductance of the choke that you have made. This is of course at the higher frequencies. It may work fairly well at 2182. The old AM whip antennas that were used on 2 and sometimes on 4 mhz and not on higher frequencies had a center loading coil wound on them. This increased their efficiency over just a straight whip and putting all the loading coil in the antenna tuner. With the coil higher up on the antenna it provided a little higher feed point impedance and resulted in a more efficient antenna. This worked well when only 2 and 4 mhz was involved. But when higher frequencies are fed to such an antenna that loading coil that worked wonders on the low frequencies acts like a choke at the higher frequencies and effectively disconnects everything above the coil, including part or most of the coil. You then have only a very short antenna working for you making it very inefficient. You could fasten a straight piece of wire to the kevlar and it should work fine. Regards Gary On Sat, 1 Nov 2003 13:32:36 -0800, "maxlynn" wrote: Okay, here's another question on antenna configuration. I have just gone through the pricing out of backstay insulators, and received the suggestion that a good, less expensive alternative would be to substitute a Kevlar backstay for the rod that I have presently, and wind a piece bare of wire around the Kevlar, up to near the masthead as an antenna. It is significantly less expensive, and the Kevlar has the advantage of being stronger and lighter than the wire. Anyone know of any disadvantages to this approach?? "john s." wrote in message . com... Glenn Ashmore wrote in message news:JRxob.119973$sp2.25191@lakeread04... In the process of laying up the hull I incorporated a couple hundred sq. ft of bronze bug screen to serve as a counterpoise. In addition two runs of 2" copper foil run down the center of the hull to the keel area. Capacitors between the foil and the keel bolts isolate any DC from getting back into the counterpoise. That is probably enough but as I am installing two aluminum tanks, I wonder how kosher it would be to tie them into the counterpoise with more capacitors. It would add another 14 sq ft of coupling area but would it be introducing other problems? Glenn, I think you are overdoing it....I just have a copper strap from the ground of the antenna tuner to one keel bolt (external lead keel) and when I tested the syste,after installation (in New York), I got a 55 report from a ham in NW Spain. The only time Herb (Southbound II) did not hear me loud and clear was because my copper strrap had become corroded/ john N2ZOA/MM |