Posts

Simple Ham Radio Antennas--Simple Loop Antenna for 20-10 meters. Post #902.

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If you're having trouble viewing this video, please insert this title link into your browser search box: https://www.youtube.com/watch?v=y3_LIQ6G6e4.  Exceptionally well made video from NG9D showing you a very simple way to design, make, and erect a vertical closed loop antenna that covers all Amateur Radio bands from 20 to 10 meters. Each construction step is thoroughly explained and shown in the video.  If you follow the instructions, you'll have little difficulty in building and using this antenna.  Attaching a coaxial feed line to the antenna is easy--just solder one end of the antenna to the center pin of the coax and the other end to the braided shield.  An antenna transmatch (i.e. "tuner" would help match the antenna impedance to the impedance of your transceiver. You would also need a vertical support of at least 30 feet/9.14 meters to get maximum performance out of this antenna.  You could also use television twin lead or 450 ohm ladder line to feed the ant

Simple Ham Radio Antennas--Construction of a 9-1 unun. Post #901.

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If you're having trouble viewing this video, please insert this title link into your browser search box: https://www.youtube.com/watch?v=L4jGNFGN-RQ.  Here's a handy 9:1 unun from m1tina that will make your use of a longwire antenna much more efficient and pleasurable.  The 9:1 unun is an impedance transformer to feed high impedance, end-fed (unbalanced) random wire antennas, which may exhibit an impedance of a few hundred ohms.  The unun transforms the impedance of the wire into something closer to 50 ohms--something your transceiver will appreciate.  The 9:1 unun is wound on a T200-2 core and has 9 trifilar turns of enamel wire.  This is a great weekend project! For the latest Amateur Radio news and information, please visit my news site at http://www.kh6jrm.info. If you're a radio amateur living on the Big Island of Hawaii, be sure to check my ARRL PIO (public information officer) blog at http://bigislandarrlnews.wordpress.com. Be sure to check out the blog sideb

Simple Ham Radio Antennas--Elevated Radial AM Antenna Grounding System Video by Nott Ltd

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If you're having trouble viewing this video, please insert this title link into your browser search box: https://www.youtube.com/watch?v=NSoUjs2JwGg. A fascinating discussion from respected broadcast engineer Ron Nott (K5YNR) as he discusses the use of elevated radial systems for AM broadcast stations.  Much of what is said in this video can be applied to amateur radio operations.   Elevated radials seem to work as well or better than radials running along the ground. There are several great articles about elevated radial systems on the internet, among them research done by C.L. Cebik and this one by Ron Nott (K5YNR), the producer of this video: "Transmission Guide:  The Elevated Radial System", Ron Nott (K5YNR), in "Radio Guide", August 2006, p. 8. For the latest Amateur Radio News and Information, please visit my news site: http://www.kh6jrm.info. Opinions expressed in this blog are mine unless otherwise stated. Thanks for joining us today! Aloha

Simple Ham Radio Antennas--Great portable HF multiband antenna. Post #899

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If you're having trouble viewing this video, please insert this title link into your browser search box: https://www.youtube.com/watch?v=oTPWYfA_uuQ. This antenna designed by Martin (G8JNJ) and built by Tom (9A5TOM) is another simple, easily erected, and versatile HF vertical antenna suitable for both emergency and portable operations.  The antenna is loosely patterned after the popular Comet CHA-250, but doesn't cost as much as the commercial model.  In this video, Tom uses a 7 meter/22.96 ft telescoping mast to support a helically wound antenna element. Like the CHA-250, the key to a successful operation is the matching transformer about midway up the mast. The video shows how the transformer is built and gives you some  SWR readings for the amateur radio bands between 80 and 10 meters. The antenna doesn't require a transmatch (i.e. "tuner") for successful operation.  Tom says the antenna works best on 40-10 meters and performs as well as the CHA-250. For th

Simple Ham Radio Antennas--5 Min Emergency Antenna. Post # 898.

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If you're having trouble viewing this video, please insert this title link into your browser search box: https://www.youtube.com/watch?v=XgyH6JQ3XHo. This project from Jerry H. Kolins (K2PFW) will get you on the air in minutes. This emergency antenna reminds me of a "sleeve dipole" where the outer shield of the coaxial cable serves as the "other half" of a dipole.  In effect, the coaxial antenna becomes a vertical dipole.  A good, useful antenna that could be used almost anywhere, including HOA/CC&R controlled housing.  Make one now and keep it as a spare antenna in your "go kit." For the latest Amateur Radio news and information, please visit my news site at http://www.kh6jrm.info. Be sure to check the blog sidebars for other antenna ideas. Opinions expressed in this blog are mine unless otherwise stated. Thanks for joining us today! Aloha es 73 de Russ (KH6JRM).