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Homebrew portable 20m whip. Posts# 1045.

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If you can't view this video, please insert this title URL into your browser search box: https://www.youtube.com/watch?v=jwMGL7X_4Nk. Intriguing video from Steven Salmon (G7DIE).  If you need an ultra simple, cheap, and effective portable antenna for the 20 meter amateur radio band , this coil-loaded vertical antenna will meet that requirement.  According to Steven, most of the parts were collected at no cost, except for the inexpensive telescoping fishing rod (about 1- pound sterling ).  Steven used an online coil calculator to compute the inductance of the loading coil .  This homebrewed vertical performed well during Steven's trip to Spain (EA3). For the latest Amateur Radio news and information, please visit these websites: http://www.HawaiiARRL.info https://oahuarrlnews.wordpress.com https://bigislandarrlnews.wordpress.com http://www.kh6jrm.info ( breaking news for radio amateurs ). Other sites of interest: http://hawaiisciencedigest.com (science and te

How to Build Several Easy Antennas for Amateur Radio. Post #1044.

How to Build Several Easy Antennas for Amateur Radio (http://www.wikihow.com/Build-Several-Easy-Antennas-for-Amateur-Radio). Accessed on 16 February 2017, 06:25 hrs, UTC. Author:  http://www.wikihow.com. Please click link or insert the title URL into your browser search box to read the full article. Comment: I found this wonderfully simple and easy-to-understand antenna tutorial while I was searching for some new antenna ideas.  Although the article may appear a bit basic for the more experience radio amateurs among us, it is perfect for the newly licensed or prospective ham radio enthusiast.  In fact, this article would make an excellent introduction in an amateur radio license class. The article covers all of the important aspects of antenna building, from basic antenna types and formulas to the types of wire and feed lines best suited for your location.  And most importantly, the discussion covers necessary safety measures involved in building your new antenna. These pa

7 Magnetic Loop Antennas for 7MHz. Post #1043.

7 Magnetic Loop Antennas for 7MHz (http://www.dxzone.com/7-magnetic-loop-antennas-for-7MHz/). Accessed on 14 February 2017, 20:35 hrs, UTC. Author:  http://www.dxzone.com compilation. Please click link or enter title URL into your browser search box to read the complete article. Comment: Small magnetic loop antennas are gaining in popularity with radio amateurs who live in deed-restricted housing (HOAs and CC&Rs) or have very small urban lots with inadequate room to erect a full-length dipole antenna. Magnetic loop antennas behave as a coil with a small radiation resistance and can be designed in several shapes to fit your operating conditions.  These antennas are small compared to 1/2 wavelength antennas, making them ideal for restricted spaces or for portable use.  Magnetic loop antennas can be designed for both receiving and transmitting. In this post, we learn how to build 7 popular magnetic loop designs: A magnetic loop for HF, covering frequencies between 3.5 a

The Perfect Dipole. Post #1042.

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If you can't view this video, please insert this title URL into your browser search box: https://www.youtube.com/watch?v=sjUcn84CMus. Here's another simple, easy-to-make, and inexpensive multiband HF antenna suitable for both home and portable operations.  In this video, Stan Gilbilisco (W1GV) shows us how to design, build, and use a variation of the all band doublet antenna which has been in use since the early 20th century. By using twin feeders, such as 450 ohm ladder line , 300 ohm television twin lead, and homemade 600 ohm balanced line fed into an automatic antenna transmatch (i.e. "tuner"), you can cover all HF amateur radio bands from 160 to 10 meters.  Just cut the dipole for the lowest frequency of use, connect a balanced feed line to the antenna elements, run the feed line into a balanced "tuner" or 4:1 balun/"tuner" combination, and use a short piece of 50 ohm coaxial cable to connect the "tuner" to your HF rig.  T

Log-Periodic Dipole Array (LPDA). Post #1041.

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If you can't view this video, please insert this title link into your browser search box: https://www.youtube.com/watch?v=KUyJKYhDvGnw. Here's an interesting, somewhat complex antenna idea for radio amateurs willing to experiment with unusual VHF /UHF antennas . When I was in the USAF , I saw these LPDA arrangements used for the upper HF bands (20 through 10 meters) and for some VHF applications.  The LPDA is a broadbanded, unidirectional antenna that is useful for DX and contest events. Stan Gibilisco (W1GV) has done a good job of explaining the theory, design, construction, and use of this often overlooked antenna.  If you can't reach that distant VHF/UHF repeater, try a LPDA. For the latest Amateur Radio news and information, please visit these websites: http://www.HawaiiARRL.info. https://oahuarrlnews.wordpress.com. https://bigislandarrlnews.wordpress.com. http://www.kh6jrm.info ( breaking news for radio amateurs). Other sites of interest: http:/