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Simple Antennas for the Amateur Radio Operator--a continuing series

KH6JRM's Amateur Radio Blog Post 165 BACK TO BASICS One of the creative things amateur radio operators can do these days is to build simple, effect wire antennas.  Although most commercial antennas are well made and perform well, there is nothing quite like building your own antenna and working DX on a shoestring budget.  So, let's begin with my favorite band--20 meters. After I took down my temporary "long wire" antenna this morning, it was time to rebuild a 20-meter antenna that had seen better days.  As mentioned in post 164, rodents and other unnamed creatures chewed on my feed lines and elements, creating an ugly mess.  Fortunately, I still had a homebrew 33-foot mast made from 2-inch pvc pipe which could be pressed into service.  I attached 16 1/2 feet of AWG 22 wire to one half of the mast and another 16 1/2 feet of wire to the bottom of the mast.  At the midway point of the mast, I attached and soldered 40-feet of 450-ohm ladder line.  The line ran i

Simple Antennas for the Amateur Radio Operator--a continuing series

KH6JRM's Amateur Radio Blog Post 164 A QUICKLY DEPLOYED "LONG WIRE" ANTENNA Most of my weekend chores are done, which gives me a few hours to play with antennas before Monday arrives.  Yes, even for those of us in the "semi-retired" category, there are things to do before the warm glow of vacuum tubes draws us back to the rf circus. I've been able to build and test numerous antenna designs over the past few weeks, thanks to a break from my substitute teaching duties.  My xyl and I expect to be called shortly for another assignment since Hawaii public schools begin during the first week of August.  So, there's lots to do--clean up the "shack", inventory equipment, and otherwise try to find stuff I misplaced over the year.  As for antennas, I decided to take down the inverted 40-meter vee for maintenance.  Rats and other small animals have chewed up some of the wire elements and a piece of coax I used to connect the 4:1 balun to the Dra
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

Mobile operations on Independence Day

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

Simple Antennas for the Amateur Radio Operator

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