Simple Ham Radio Antennas

KH6JRM's Amateur Radio Blog, post 163 An emergency 6-meter antenna Although 6-meter openings to Hawaii are fairly rare, many of us amateurs on Hawaii Island look forward to times when the "magic band" is open.  As is often the case, when 6-meters and 2-meters "open up" to the U.S. mainland, amateurs in the central Pacific often don't have a decent 6-meter antenna available when propagation is favorable.  By the time  I get home to tune in the 6-meter signals, most of the action has already past and many signals have disappeared into the noise.  Such is the state of the ionosphere. However, I think there is a way to keep on top of 6-meters without an outlay of additional funds.  Of course, it helps to have a rig that can cover 6 - meters--most of the current HF  rigs from Kenwood, Yaesu, Icom, and Alinco cover the band.  Or in my case, I can resort to an old Heathkit 6-meter rig in the storage room for such emergencies. As for antennas, you may have

KH6JRM's Amateur Radio Blog, post 162 Topic:  Mobile operations on Independence Day Happy 236th Birthday to the United States of America.  As is the custom in this country, the national holiday is reserved for barbecues, sporting events, parties, fireworks, and just kicking back and enjoying what we fought for over these past 2 1/4 centuries.  Those celebrating the holiday on Hawaii Island have some added attractions, such as classic car cruises, outrigger canoe races, parades, and special concerts of Hawaiian music.  This will turn out to be quite a noisy affair.  Everything should return to something close to "normal" on Thursday.  This year, I'm getting away from all of the noise, heavy traffic, and crowded beaches to operate HF mobile and portable in my own neighborhood.  Over the past few weekends, I've been using my emergency mobile set up in the van to operate from highlands above my qth.  When the Laupahoehoe Sugar Company closed its doors in the mi

KH6JRM's Amateur Radio Blog A simple 40 and 15 meter antenna you can build in just a few minutes Sometimes it is possible to operate two or more bands with one antenna and a short run of good quality coaxial cable.  A simple 40 and 15 meter antenna, used either as a dipole or as an inverted vee, will provide hours of enjoyable contacts at modest power levels. I've built several variants of this antenna, with the inverted vee configuration preferred because of my limited backyard space.  An antenna cut for 40 meter operation can be used on  15 meters because dipoles have harmonic resonances at odd multiples of their resonant frequencies.  Because 21 MHz is the third harmonic of 7 MHz, a simple 40 meter antenna (approximately 33 feet on each side of a center connector) can be used for both 15 and 40 meters.  There is one drawback to this wonderful plan.  The idea works if you cut the 40 meter dipole for use in the cw portion of the band, for example around 7.010 MHz.  As y

KH6JRM's Amateur Radio Blog, post 160 NEW USES FOR OLD COAXIAL CABLE ANTI-THEFT PROTECTION FOR EQUIPMENT One of the things I enjoy when I'm not behind the key or microphone at my amateur radio station is reading historical material pertaining to amateur radio.  This sub-branch of the amateur radio hobby has given me several ideas on antenna improvement, reusing old materials in new ways, and protecting valuable equipment with a minimum of effort. What do you do with old coaxial cable?  I tend to follow the advice of E.A. "Whit" Whitney, W1LLD, who wrote a brief article about reusing lossy cable in the 11th Edition of "Hints and Kinks for the Radio Amateur" (published by the ARRL in 1982).  Whit's article is found on page 5-13 of this excellent compendium of practical ideas from past issues of "QST", the official journal of the American Radio Relay League.  In Whit's own words, coaxial cable "that's become too lossy for u

PURPOSE OF THIS SITE Over the past few days, some of my readers have asked why I put this site together and to whom  the information is directed.  These are fair questions, since my interest in Amateur Radio (Ham Radio) may be far from your concerns. I have two reasons for writing this blog: 1.  The blog serves as a personal journal about my journey through interpersonal communications and my love for all things electronic.  I've been a licensed amateur radio operator for 35 years.  I've enjoyed every moment of the experience, from building equipment to designing my own antennas (the things that launch signals into the atmosphere).  I was fortunate to have had a good electronics background courtesy of the United States Air Force and over 40 years in the commercial broadcast business.  Very early in my radio journey, I helped design and build the student FM radio station at the University of Hawaii (Manoa), worked at various radio stations, and even put a part 15 (unlicen

SOMETHING DIFFERENT FOR THE ANTENNA EXPERIMENTER The weather has improved to a point that I can get outside and play with antennas again.  Other than a twice-daily walk and jog with my xyl, the weather has kept both of us inside.  June on Hawaii Island often brings many days of showers, and this past week was no exception.  So, when the sun finally broke out for several hours, I rushed through my daily chores and proceeded to the postage stamp lot in back of our rental house for some serious antenna work. Because the inverted vee, loop, and "upper and outer" antenna were doing well, I decided to make a vertical helix for 40 meters using some short pvc pipe, extra #22 AWG wire in the shack, and some 450-ohm balanced line into a balun and the trusty Drake MN-4 ATU. According to information I found in several ARRL publications, a quarter wave vertical could be created by winding a half wavelength of wire around a sturdy pole and topping the end with a capacitance hat.  I&

A VHF ANTENNA FOR YOUR APARTMENT Apartment dwellers face unusual antenna problems, whether they be the  installation of HF antennas or VHF antennas.  Like many of you, I've resorted to using my handheld attached to a mag mount atop a refrigerator or other piece of interior metal.  While this arrangement works, it can be unsightly or even dangerous. It seems Yvon Laplante, VE2AOW, has come up with an apartment antenna which is not only effective and cheap, but also disguiseable and safe.  Laplante's idea can be found in the "Hints & Kinks" column of "QST" for July 2012.  In Laplante's words, "I made a small dipole antenna using telescoping antennas I took from old, broken FM radios.  The antenna is mounted on a...3 x 5 inch piece of Plexiglas with two suction cups.  With my radio placed close to a window, I attached the antenna to the window and adjusted the two elements for 2 meters--about 19 inches.  The antenna gives very good results.&qu