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Simple Ham Radio Antennas: A Portable 2 meter/70 cm Ham Radio Antenna. Post #303

KF7ETX has built an easily assembled portable VHF/UHF antenna system that can be set up most anywhere, from your home to an emergency station in the country. All it requires a painter's pole support mast , three paracord guy ropes , a dual-band 2 meter /70 meter antenna, and some low-loss coaxial cable. I have a similar arrangement at my QTH, where I use a homebrewed 5/8 wavelength 2 meter antenna supported by a 33-ft/10.06 MFJ telescoping fiberglass mast. The mast is secured by clamps on the side of my garage. I feed the antenna with 50-ft/15.24 meters of RG-213 coaxial cable. The mast can also be broken down for portable use. The antenna works very well from my rural location. The antenna used in this video by KF7ETX can be made from locally available materials from the nearest hardware or home improvement outlet. This is a simple, effective antenna that will give you hours of fun at your favorite park, beach, or mountain top. Have fun. Aloha es 73 de KH6JRM.

Simple Ham Radio Antennas: Stealth Amateur Radio Antenna System (7 MHz to 1.3 GHz) AKA HDTV antenna. Post #302.

Here's a curious design for a stealth antenna from Jim Whitaker . The antenna appears to be a type of Off Center Fed Dipole ( OFCD ) capable of working on 40, 20, 15, 10, 6 meters . The antenna functions as a discone for 6 meters, 2 meters, and 70 cm. I've built a few OFCD antennas , but they didn't look like Jim's. You may want to test Jim's idea if your antenna space is limited or discouraged by HOAs and CC&Rs.For the latest Amateur Radio News and Events, please check the blog sidebars. These news feeds are updated daily. Aloha es 73 de Russ (KH6JRM).

Simple Ham Radio Antennas. The Open-Wire Dipole (Doublet). Post #293

I'm still in the process of restoring my "antenna farm" after the passing of Tropical Storm Iselle on 07-08 August 2014.  I lost a few trees on my Orchidland Estates property, most of which were supporting several HF wire antennas.  I salvaged most of the wire and the 450 ohm feedline from the storm.  While I cleaned up the mess, I erected a simple multiband vertical antenna using a tall Norfolk Pine Tree as an antenna support. Next on the list is the restoration of my approximately 134-ft/40.85 meters  center-fed horizontal dipole.  The antenna is fed with 450 ohm ladder line which goes into a W9INN 4:1 balun and then via a short length of RG-8X coax into a MFJ 941E Versa Tuner II.  This feed arrangement allows multiband coverage from 3.500 MHz through 29.000 MHz. Although the antenna requires two tall supports (trees or masts), construction of the antenna is simple and the dipole doesn't require a ground radial system. Using the general formula, 468/f(

The Pine Tree HF Stealth Vertical Antenna. Post #289.

Now that Tropical Storm Iselle has left the state of Hawaii , those of us on Hawaii Island can complete the massive task of clearing roads, restoring power, and, in some cases, rebuilding our homes. Damage to my home was minimal with only fallen trees and "disassembled" wire antennas to be cleared from the property.  Our subdivision in the Orchidland Estates area of the Puna District escaped serious damage with only power interruption and blocked roads presenting major difficulties. When I surveyed the damage after the passing of the storm (07-08 August 2014), it soon became apparent that most of my "antenna farm" would have to be rebuilt.  The only antennas left intact were the 40/15 meter inverted vee and the NVIS 40 meter loop, which were lowered before the storm.  My 135-foot/41.15 meters doublet lodged in a 45-foot/13.71 meters tall eucalyptus tree was torn to shreds by windblown branches and fallen debris.  I did salvage the 450-ohm ladder line , a few

Simple Ham Radio Antennas. A 20 meter through 10 meter Vertical Dipole Antenna. Post #284.

One of the joys of moving into a bigger home with a decent back yard (1 acre of mixed brush and trees) is the ability to build the wire antennas I've always wanted.  Like many of my fellow amateur radio operators, I've endured HOAs, CC &Rs , and limited space for most of my 37 years as a ham.  I operated fairly well under these circumstances using stealth antennas from "ground hugging" loops to thin random wires stretching to the nearest tree. Now that my xyl and I are semi-retired, we have to the time to "fix up" our final home in an area conducive to our various hobbies, including gardening, amateur radio, backyard astronomy, and just plain relaxing.   Over the past few months, I've begun the erection of my "antenna farm" and the building of my radio room in the garage.  There's a lot of work to be done, but it's enjoyable and gives me exercise. Last Friday, just before the 2014 ARRL Field Day, I completed a new antenna whi

Simple Ham Radio Antennas. On the ground antennas. Post #280

Over the past few weeks, I've become fascinated with antennas mounted on or near the ground. I've even built a few, such as Mike Toia's (K3MT) "grasswire" antenna and a similar "earth" antenna from Australia.  A few months ago, I built a simple beverage antenna for my old Hallicrafters SX-62A receiver.  All or these wire antennas worked very well, especially for the AM broadcast band . With a few modifications, these wires can be used as a separate receive antenna for amateur radio stations located in noisy or desert areas.  I've used vertical antennas for transmitting and low-mounted antennas for receiving.   So, what are these ground hugging "long wires?" According to articles published in the "NASWA Journal" for December 1992 and January 1993 by author Joseph Buch, these antennas mounted on, near, or slightly below ground level are called "wave" antennas because "they extract energy from the wave as it tr

Simple Ham Radio Antennas: The "Down To Earth Antenna." Post #279

Are you looking for an inconspicuous amateur radio antenna that is largely invisible, yet delivers acceptable DX and local results?  An antenna idea described by Robert McGregor (VK3XZ) and published in the May, 1993 edition of " Amateur Radio " (Australian magazine) may suggest a few alternatives for hams facing restrictive HOAs and CC&Rs. A few weeks ago, Dean Manley (KH6B), gave me a copy of this fascinating article for my antenna reference library.  I've built several disguised antennas, ranging from K3MT's "grasswire" antenna to low-lying dipoles running just above my home garden.  But none of this antennas worked as well as "The Down To Earth Antenna" from Robert McGregor (VK3XZ). Here are some pertinent paragraphs from Robert's article. DOWN TO EARTH ANTENNA Australia and the African Desert have a common need for radio communication and a mainly sandy terrain. VK5TL's letter, AR Jan. '92 caused me to dig deep into a

Simple Ham Radio Antennas. A basic 40/15 meter dipole. Post #276

My antenna "farm" at the new QTH finally is taking shape. So far, I've built and used successfully a 40-10 meter inverted V fed with ladder line , a 5/8 wavelength vertical for 20, 15, and 10 meters, a 135-ft/41.15 meters "classic doublet" fed with ladder line that works from 80-10 meters, and a 40-10 meter delta loop fed with ladder line.  I've described these antennas in past posts.  All of them work very well with relatively low power (less than 50 watts) with my older rigs (Argosy II, Swan 100 MX, Yaesu FT-7, and a Kenwood TS-520). Although I prefer multiband HF antennas fed with 450-ohm ladder line, I still use a few single or two-band antennas fed with 50-ohm coaxial cable when I wish to experiment on 40 or 15 meters.  Last Sunday, 18 May 2014, I decided to build a simple two-band dipole covering the 40 and 15 meter bands using a single piece of RG -8X coaxial cable. The dipole would be designed for the lowest frequency range and then use the thir

Simple Ham Radio Antennas: A 5/8 wavelength vertical ground plane. Post #272

According to Edward M. Noll (W3FQJ), "The 5/8-wavelength vertical is a preferred length for the best low angle radiation."  For the higher HF bands (20 through 10 meters), this antenna is easily assembled and requires a small quantity of wire, some ceramic insulators, a suitable mast, 50-ohm feed line or 450-ohm feed line, a simple ground radial system, and a sturdy antenna matchbox or ATU .  Multiband use between 20 and 10 meters is possible with 450-ohm ladder line , ATU, and a balun, while good single band use can be obtained with 50-ohm coaxial cable and an inline or base antenna "tuner". So, let's build a simple 5/8 wavelength vertical for the 10 meter amateur radio band, centering on 28.4 MHz .  This frequency is at the mid-point of the SSB allocation for Technician Class licensees.  The antenna was built at my new home in the Puna District on 18 April 2014. MATERIALS: Using the general formula, 585/f (MHz)=L (ft), our vertical element will measur

Simple Ham Radio Antennas: The Ghost of Antennas Past. Post #267

Humans tend to collect things.  Amateur radio operators are no exception.  In my 37 years as a licensed amateur radio operator, I've collected enough electronics-related material to fill most of my garage/radio shack at my new home in the Puna District .  Fortunately, I've managed to keep things organized, more or less, with plastic storage bins and some old filing cabinets. During the ongoing moving process, I discovered antennas, books, logs, and parts once given up for lost.  Such was the case Monday, 17 March 2014, when I reorganizing some of the material brought to the new QTH.  I found several well-sealed boxes containing some of my successful antenna projects.  All the antennas were dipoles built during my over three decades of "warming the ether" with a variety of old tube rigs long since gone to to the great capacitor in the sky.  After I finished using these antennas, I had the foresight to clean and store them for future use.  Also along the back wall wa

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