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

This has been a very busy day.  My xyl and I were asked to help with the annual May Day Celebration today at Laupahoehoe High School.  The students put on quite a show with Hawaiian Hula, chants, stories, and local music.  In the course of the day's events, several students asked about the antenna on the roof of my Odyssey van.  After I told them the antenna wasn't for CB, but rather for amateur radio, they seemed more interested in seeing what my modest rig would do.  So, I selected a frequency for one of the FM repeaters on the island of Maui and had a good time introducing some students to my fellow hams.  I also showed them my emergency HF setup behind the final row of seats.  I didn't have the HF antenna mounted, so I just let them look at the equipment (Yaesu FT-7), the huge deep cycle marine battery, the hamsticks near the sliding door, and the mag mount nestled under the last row of seats.  Too bad I wasn't better prepared for a show, but the VHF demonstration

Simple Antennas for Amateur Radio Operators--a continuing series

THE FEEDING AND CARE OF THE INVERTED "V" ANTENNA In my last post, I described a simple inverted vee that could be built and erected by one person at a modest cost.  In my case, I had enough wire and and pvc mast sections to build this 40-10 meter antenna without going to the nearest hardware store.  Fortunately, I also had a hundred or so feet of 450-ohm twinlead, a spare 4:1 balun, and a good ATU (Drake MN-4) to finish the job.  With each leg of the "v" 33-feet long, you have an antenna that can work from 40 to 10 meters.  If you want to explore 80 meters, make both legs of the "v" 65-feet long.  These measurements are approximate--you may have to trim each leg a few inches to make a better match. If you don't have twin lead, you can also use approximately 40 to 50 feet of coax to feed the antenna.  Of course, the coax will feel happiest on one band and its third harmonic.  That characteristic makes it possible to use a 40-meter inverted "v&

Simple Antennas for the Radio Amateur--a continuing series

How would you like to build a cheap, easily erected, and efficient antenna for your small yard?  I've pondered that idea over the past several days after a cold front and its associated high winds made a mess of my temporary, homebrew vertical next to my garage.  Since I had a few days off from my substitute teaching assignments, I decided to build another sky hook with materials I had in my "junk box."  I still had a good pvc mast, about 100 feet of number 14 housewire, and an extra 4:1 balun stashed in the corner near the washing machine.  Along with 50 feet of 450 ohm twin lead and about 20 feet of RG-6 coax, I was in business. The antenna would be an inverted "vee" inspired by a variety of articles in the ARRL Antenna Book, various amateur radio forums (e.ham, net), and a 1998 paper entitled "The $4 Special" by Joe Tyburczy, W1FGH.  The antenna won't rival a mono band beam on a 50-foot tower, but it will provide hours of good contacts at a sm

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

Do you remember your first amateur radio antenna?  I certainly do.  It was ugly, fed by cheap RG-58 coax, and connected to my first rig, the Heathkit HW-101.  I called it a dipole only because each side of the Budwig connector had 33-feet of 20-gauge wire attached.  The ends of this homebrew skyhook were attached to two trees about 35-feet high in the back yard of the teachers' cottage near the Honokaa High School.  That was 36 years ago--a time long gone except for my memory of many contacts as a novice and techncian class operator.  I surely had fun with this crude antenna.  It was home made and it was my own. Now jump forward to 2012.  I've been a general, advanced, and extra class ham since those glory days 3 1/2 decades ago.  I've gone through many rigs (most of them second-hand and well-used) and several types of antennas.  Yet, I still haven't lost the excitement of those novice class days.  For me, designing and erecting antennas are still fun, educational, an

Mentoring ("elmering") Young Hams

Today, I had a break from my normal substitute teaching duties at Laupahoehoe High and Elementary School.  Now that I had a free day, I could spend a few hours catching up on email and various amateur-related posts. I came across an interesting  article in today's edition of eham.net, which encapsulated much of what I feel is right with amateur radio.  Don Keith, N4KC, wrote a nicely-paced short story called "A Dark and Stormy Night".  The plot revolves around a back porch discussion between a newly licensed 15-year old ham and two older hams, who happen to be husband and wife.  The trio was reviewing what it meant to be an amateur radio operator while a thunderstorm and a power outage played out on a warm summer night.  All of the usual reasons for being an amateur radio operator and the service hams bring to their communities are given in an easy to understand, conversational tone.  Keith has the unusual ability to make you feel part of the story. What impressed me

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

Those of us forced to use compromise antennas brought on by limited real estate, restrictive CCRs, and HOA (home owner associations) may have another way to enjoy amateur radio without worrying about the neighbors.  The May 2012 edition of "QST" has several interesting articles about HF digital operations.  I was most interested in an article by Steve Ford, WB8IMY, called "Who's on JT65?"  Despite its limitations, this mode for moonbounce communication developed by Dr. Joe Taylor, K1JT, is becoming more popular as the year rolls on.  Ford says, "the key to JT65's burgeoning popularity is found in the fact that you can use it to make contacts over great distances with a few watts and just about any antenna.  As you can imagine, hams confined to indoor operating have embraced JT65 with a passion."  Ford goes on to describe the experiences of Ron Kolarik, K0IDT, and Sergey Kohno, UR3CTB, in Ukraine as models of what this mode can do.  There are limita

Simple antennas for the Hawaii Island Amateur Radio Operator--a continuing series

Have you ever thought of installing a small, portable HF rig and collapsable antenna in your vehicle for impromptu or emergency operations?  During the past week, wet weather and sometimes marginal road conditions got me thinking about what HF radio system I would use should a traffic emergency arise where I couldn't get home or where cell phone coverage would be unusable.  Along the Hamakua Coast of Hawaii Island, cell phone coverage is spotty and there are many areas inadequately served by this handy communications device.  Geography plays a big role in limiting cell phone coverage, with mountain peaks and ridges often degrade the signal available. So, last week I decided to make a small upgrade in my mobile capability with the creation of a small, easily portable HF system to complement my bare-bones 2-meter capability (HT with mag-mount antenna on the rood of my van).  I selected my old, trustworthy Yaesu FT-7 (10 watts output), a large marine, deep cycle battery in the garag