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Showing posts with the label Near Vertical Incidence Skywave

Simple Ham Radio Antennas: The "Fencetenna". Post #266

Building wire antennas is one of the few amateur radio activities that remains fairly inexpensive.  Your nearest hardware store or home improvement outlet is chocked full of wire, connectors, pvc pipe, copper tubing, and basic tools to launch your antenna building efforts. Whether you make simple dipoles, inverted vees, loops, or even directional vertical arrays, the satisfaction of having built something that links you to your fellow amateurs around the world is beyond compare.  If the antenna doesn't meet your expectations, you can salvage most of your material and try again.  It's all part of a continuing educational experience that can last a lifetime.  Add to this mix a few simple transceiver kits or accessories and you have something that will be your faithful radio companion for many years. I approach my antenna "adventures" with that sort of mindset, and I'm always on the lookout for intriguing antenna ideas that I can modify for my own use. Such wa

Simple Ham Radio Antennas: An 80-10 meter inverted vee dipole. Post #263

A few days ago I read a fascinating antenna article by Cecil Moore (W5DXP) on the http://www.eham.net website.  Cecil described what he called a " Multi-Band 33-ft dipole" that works on 20, 17, 15, and 10 meters without an antenna "tuner" (i.e. transmatch ).  The secret to this outstanding antenna was the use of 450 ohm ladder line in conjunction with a series of switches and relays that selected the proper length of ladder line used to feed the antenna.  Depending on the band of use, Cecil could insert and remove sections of ladder line with his relay/switch system so that swr across his chosen band remained low.  By carefully selecting which section of feed line to add or subtract, he got a decent performing antenna without having to resort to a transmatch or "tuner." Cecil's idea got me thinking of ways to improve the dipoles I'm using at my new home site.  Although his idea has a lot of merit, I felt the need to build something a bit simpl