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Showing posts from February, 2017

Ultra light portable radio System. Post #1057.

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If you're unable to view this video, please insert this title link into your browser search box: https://www.youtube.com/watch?v=dmxDUmV5xbk.

Thanks to Duane (BlueJay 1968) for this simple, portable 2 meter radio system. This "ultra light" system can fit in a small carry bag and is suitable for a variety of backpacking, portable, and emergency situations.  Nicely done video with clear instructions.

For the latest Amateur Radio news and information, please visit these sites:

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 technology news for radio amateurs).
https://hawaiiintelligence digest.com (trends in geopolitical intelligence, strategic forecasting, terrorism, and cybersecurity).

Be sure to check the blog sidebars for additional antenna and propagation articles.

Opinions expressed i…

Windom Antenna. Post#1056.

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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=5P0fZYzCUE.

Here's another classic HF antenna worth trying.  In this video, Stan Gibilisco (W1GV) introduces us to the Windom Antenna and explains the theory, design, and operation of this "oldie but goodie" from the early 20th century.  Modern versions of this antenna can be fed with balanced feed line and used with an antenna transmatch (i.e. "tuner") to gain multiband HF operation.

For the latest Amateur Radio news and information, please visit these sites:

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 technology news for radio amateurs).
https://hawaiiintelligencedigest.com (trends in geopolitical intelligence, strategic forecasting, terrorism, and…

Amatuer Radio RF Safety Calculator. Post #1055.

Amateur Radio RF Safety Calculator
(http://www.hinklink.com/power_density.htm).
Accessed on 26 February 2017, 23:55 hrs, UTC.
Author:  Paul Evans (VP9KF).
Please click link or enter title URL into your browser search box to read the full article.

Comment:

Here's a handy reference guide from Paul Evans (VP9KF) that will help you determine how much RF exposure you and your family are getting from your amateur radio operations.

All you have to do is fill in the appropriate forms on this calculator to find out the exposure levels from your HF/VHF/UHF antennas.  Paul also provides key links to various FCC and University RF studies concerning RF exposure.

Please bookmark Paul's website so you can refer to it after you build or modify your antennas.

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 amate…

Ham Radio - Build your own L network antenna tuner

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If you can't view this video, please insert this title URL int your browser search box: https://youtube.com/watch?v=EXD9rAOM_o4. This is post #1054 in a continuing series of Simple Ham Radio Antennas.

Here's a handy device that will increase your enjoyment of amateur radio while protecting your HF transceiver from excessive SWR.  SWR protection is particularly important with end-fed half wavelength wire antennas and random length wires used during portable and emergency operations.

Kevin Loughin (KIB9RLW) shows us how to design, build, and use a simple, inexpensive L network antenna transmatch (i.e. "tuner") that will enable you to use a variety of random length wire antennas without worrying about excessive SWR or RF feedback in the shack.  The video is well-produced and explains in simple terms how to build this valuable accessory to your ham shack.

For the latest Amateur Radio news and information, please visit these websites:

http://www.HawaiiARRL.info.
https:…

Zepp Antenna Theory. Post #1053.

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If you can't view this video, please insert this title URL into your browser search box: https://www.youtube.watch?v=TwYSS335wZw.

Here's another classic amateur radio antenna you may want to try if you're in an experimental frame of mind.  This antenna is patterned after the HF antennas used on Zeppelin airships during the 1920s and 1930s.

Stan Gibilisco (W1GV) does an excellent job of explaining the theory, design, construction, and use of this legacy multiband HF antenna.

For the latest Amateur Radio news and information, please visit these websites:

http://www.HawaiiARRL.info.
https://oahuarrlnews.wordpress.com.
https://bigislandarrlsnews.wordpress.com.
http://www.kh6jrm.com (breaking news for radio amateurs).

Be sure to check out the blog sidebars for additional antenna and propagation articles.

Opinions expressed in this blog are mine unless otherwise stated.

Thanks for joining us today!

Aloha es 73 de Russ (KH6JRM)

Three-Wire Dipole Antenna. Post #1052.

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If you can't view this video, please enter this title URL into your browser search box: https://www.youtube.com/watch?v=zWWhNBrx4I.

Here's an interesting dipole design for antenna experimenters.  The three-wire folded dipole or T3FD was popular during the 1950s and 1960s, with several companies, including B & W, marketing the antenna to the military, commercial interests, and radio amateurs.  The antenna has a broad bandwidth, high impedance, and exhibits high efficiency.

In this video, Stan Gibilisco (W1GV) explains the theory, design, and operation of this classic antenna.  In Stan's version, the 1/2 wavelength top section consists of three parallel elements, with the center element connected to a balanced feedline, which goes to a transmatch (i.e. "tuner") and then to your HF transceiver.

Although this antenna is a bit of a curiosity, you may want to build one just to see what it can do for your signal.

For the latest Amateur Radio news and information, …

Converting Radio Shack CB Antenna to 2m. Post #1051.

Converting Radio Shack CB Antenna to 2m
(http://www.dxzone.com/cgi-bin/dir/jump2.cgi?ID=32533).
Accessed on 22 February 2017, 21:35 hrs, UTC.
Author:  W6OT.
Please click link or enter title URL into your browser search box to read the full article.

Comment:

You never know where antenna materials can be found.  In this article, W6OT converts an old "found" magnetic mount CB antenna into a useful 1/4 wavelength 2 meter antenna.  Although I've converted several Radio Shack 102 inch/259.02 cm steel whips into 10 meter vertical antennas, I have yet to change one of these old shorted CB antennas from 11 meters to 2 meters.

By adding a short length of brass rod to the original whip and attaching a coiled 19 inch/48.26 cm counterpoise wire, W6OT was able to cut and trim the antenna so it resonated in the middle of the 2 meter Amateur Radio Band (around 146.0444 MHz).

Rather than toss that old CB antenna (full-length or "shorty" version), try converting it to some othe…

A Quick, Simple, Inexpensive Trailer Hitch Antenna Mast. Post #1050.

A Quick, Simple, Inexpensive Trailer Hitch Antenna Mast
(http://www.eham.net/articles/38039).
Accessed on 21 February 2017, 21:35 hrs, UTC.
Author:  Joe Tomasone (AB2M).
Please click link or insert title URL into your browser search box to read the complete article.

Comment:

A nice, well-written, and richly photographed tutorial on building a sturdy, inexpensive trailer hitch antenna mast.  Just follow the suggestions outlined in this article and you should have little trouble attaching the hitch to your vehicle and supporting a lightweight antenna for portable operations.

In the comment section of the article, KE4ZHH suggests using a telescoping fiberglass mast with the trailer hitch.  One could easily use the tip of the fiberglass mast to support an inverted vee antenna.  Either way, this article is a good example of what can be done with simple materials.

For the latest Amateur Radio news and information, please visit these sites:

http://www.HawaiiARRL.info.
https://oahuarrlnews.w…

No Tuner "Shorty" HF-Band Antenna. Post #1049.

No Tuner "Shorty" HF-Band Antenna
(http://www.w5dxp.com/notuner/shorty.fig).
Accessed on 20 February 2017, 20:15 hrs, UTC.
Author:  W5DXP.
Please click link or insert title URL into your browser search box to read the article.

Comment:

I found this article by W5DXP while I was looking for an easy, inexpensive, and portable HF multiband antenna for my home-in-progress in Hawaii Island's Puna District.  Clearing an acre of land is a slow, tedious process, but, taking a break for some amateur radio contacts, reinvigorates my spirits.  I wanted an antenna that could be erected quickly between two Norfolk Pine trees in my back yard.
The design from W5DXP is self-explanatory with all of the details necessary to build this simple, effective antenna.  If you build this antenna according to the illustration from W5DXP, you should have good results.  Best of all, there is no antenna transmatch (i.e. "tuner") involved.

For the latest Amateur Radio news and information, p…

40/20/10 Meter Fan Dipole Attic Antenna. Post #1048.

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40/20/10 Meter Fan Dipole Antenna
(http://www.worldwidedx.com/threads/40-20-10-meter-fan-dipole-attic-antenna.178104/).
Author:  KD2GOE.
Accessed on 20 February 2017, 00:35 hrs, UTC.
Please click link or insert title URL into your browser search box to read the full article.

Comment:

If you have a large enough attic in your deed-controlled home, you may find this variant of the fan dipole just what you need to get on the air and enjoy the challenge of amateur radio.

KD2GOE does an excellent job of explaining how he built this effective, inexpensive stealth antenna that covers the 40, 20, and 10 meter bands. With a little help from an antenna transmatch (i.e. "tuner"), this antenna will work fairly well on 12 and 17 meters.  The photographs are excellent and give you an excellent illustration of what can be done in a limited space.

For the latest Amateur Radio news and information, please visit these sites:

http://www.HawaiiARRL.info.
https://oahuarrlnews.wordpress.com.
https…

Coil-shortened dipole antenna calculator. Post #1047.

Coil-shortened dipole antenna calculator
(http://www.dxzone.com/cgi-bin/dir/jump2.cgi?ID=32516).
Author:  J.J. Johnson
Accessed on 18 February 2017, 19:50 hrs, UTC.
Please click link or insert title URL into your browser search box to read the full article.

Comment:

Here's another useful tool for antenna experimenters. With the suggestions given in this article, you can design, build, and use an effective dipole antenna that needs much less space than a full-sized dipole by adding two simple, inexpensive loading coils.

The article provides a simple set of formulas to help you through the design and building process.  The author also supplies a simple coil inductance calculator and a link to a related article by Jerry Hall (K1PLP) in the September 1974 issue of "QST".

For the latest Amateur Radio news and information, please visit these sites:

http://www.HawaiiARRL.info.
https://oahuarrlnews.wordpress.com.
https://bigislandarrlnews.wordpress.com.
http://www.kh6jrm.info (b…

Stealth Ham Antenna Beating the HOA. Post #1046.

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If you can't view this video, please enter this title URL into your browser search box: https://www.youtube.com/watch?v=4CQ3WDcfYBU.  Here's another creative idea for an antenna in a deed-restricted home.  Apparently, the beautiful bird house at the top of Rich Rogers's mast is permitted, so he modified his 53 foot/16.158 meters Ultimax DXtreme End Fed Antenna to fit the limitations of his property. Rich says he's able to return to the air with no one suspecting that the bird house (which is actually used by birds on his lot) is disguising his HF amateur radio antenna.

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 technology news for radio amateurs).
https://hawaiiintelligencedigest.com (trends in geopoli…

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 technology news for radio…

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 paragraphs fro…

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 and 10 MHz.  …

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.  This is a ba…

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://hawaiisciencedigest.com …

7 Ideas For Indoor Antennas. Post #1040.

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7 Ideas For Indoor Antennas
(http://www.dxzone.com/7-ideas-for-indoor-antennas).
Accessed on 12 February 2017, 02:55 hrs, UTC.
Author: A series of articles compiled by http://www.dxzone.com.
Please click link or enter title URL into your browser search box to read the full article.

Comment:

I found this fascinating article today while I was searching for some experimental antenna designs.  Having once lived in a "no antenna" HOA/CC&R neighborhood, I remember how frustrating it was to design and build an indoor antenna to get me on the air. After a few botched experiments, I finally was able to build a simple indoor loop fed by 450 ohm ladder line to get on HF and a simple VHF ground plane antenna for my 2 meter work.

This collection of indoor antenna projects should give you some ideas of what can be done to get on the air from deed-restricted housing.

Try some of these indoor antennas and see if you can find a way to get on the air. Being off the air is no fun.  Even a …

Russian QRP with a handcrafted magnetic loop. Post #1039.

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Russian QRP with a handcrafted magnetic loop.
(http://www.amateurradio.com/russian-qrp-with-a-handcrafted-magnetic-loop/).
Accessed on 11 February 2017, 04:55 hrs, UTC.
Author:  Peter Dabizha (R2ABT).
Please click link or insert title URL into your browser search box to read the full article.

Comment:

According to Moscowradio amateur Peter Dabizha (R2ABY), many hams in the Russian Federation are enjoying operating "in the field" with portable QRP rigs and homemade antennas, such as the magnetic loop featured in this article. Some of the antennas used by Russian QRP enthusiasts are very short, with many vertical antennas measuring only 3 meters/9.84 feet long.  Add to this mix, the cold Russian winters and you have a real survival operation for not only the well bundled operators but also for their assortment of portable rigs.  Such events are becoming popular in the United States as well, usually held under the title of "Winter Field Days." It pays to practice for …

The K2MIJ 30 meter "Limbo Stick" antenna. Post #1038.

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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=L3coh5JXZOA.

Here's a 30 meter vertical antenna that is only 9 inches/22.86 cm tall, including the "halo" which serves as a "top hat."  According "visualjuiceman", the antenna works quite well on the 30 meter Amateur Radio band and exhibits a low SWR (see photo of the MFJ HF/VHF SWR Analyzer, model MFJ-259B).  The coil consists of a 2 inch/5.08 cm PVC form using 26-24 AWG wire. The radiator is made from #10 AWG wire.  This antenna is very "stealthy" and could be used in deed-restricted properties. Why not make one of these super small antennas and have some fun?

For the latest Amateur Radio news and information, please visit these sites:

http://www.HawaiiARRL.info.
https://oahuarrlnews.wordpress.com.
https://bigislandarrlnews.wordpress.com.
http://www.kh6jrm.blogspot.com (breaking news for radio amateurs).

Other sites…

KD7DHB 6 meter halo Antenna Trial version 1.0. Post #1037.

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If you're having trouble viewing this video, please enter this title URL into your browser search box: https://www.youtube.com/watch?v=v0Tb_hXYUIQ.
Here's a simple, basic halo antenna that will get you on the often exciting and somewhat challenging 6 meter amateur radio band.  This band is often called the "Magic Band" because of its HF and VHF characteristics. This short video from KD7DHB shows one way of building an inexpensive, yet effective antenna for this band. Most of the materials can be found at the nearest building supply or home improvement center.  You may have to buy the coaxial cable from a ham radio store.  A few hours effort will reward you with a basic antenna that performs well and is easy to raise and lower.

For the latest Amateur Radio news and information, please visit these sites:

http://www.HawaiiARRL.info.
https://oahuarrlnews.wordpress.com.
https://bigislandarrlnews.wordpress.com.
http://www.kh6jrm.info (breaking news for radio amateurs).

O…