Wednesday, October 26, 2011

Simple antennas for the Hawaii Amateur Radio Operator, part 14

Final step completed--new career awaits

After 3 weeks of intensive study and three exams, I finally finished my substitute teacher course and submitted all of the necessary paperwork.  In a short time I should be getting my certificate and the opportunity to end this lifetime as a teacher.  It's sort of ironic.  Before I became an amateur radio operator back in 1977, I started out as a teacher.  Life took its inevitable twists and turns, with work ranging from an air force officer to a radio newsman and broadcast engineer.  And now, I've come full circle.  I'll end my days as a teacher.  The circle is closed.

More time for Amateur Radio

Between teaching assignments, I can devote more time to my main diversion all these years--Amateur Radio.  I hope to get on the air more often and build more antennas.  Speaking of which, I was reading a 1978 edition of "The ARRL Antenna Anthology" and came upon a simple ground plane antenna that should fit in my small backyard.  On page 19, Arthur S. Gillespie, Jr. (K4TP) described a simple, yet effective antenna for 20-meter enthusiasts.  "A multi groundplane vertical antenna with tuned feeders" is straightforward and may provide a decent antenna for those facing severe space restrictions (like I do).  The antenna is just a 16'9" piece of wire or tubing supported on a pole with four 16' 9" radials running from the base of the antenna.  The arrangement is fed with what appears to be 450-ohm twin lead to an antenna tuner.  I built and tried this antenna over the past weekend and it works very well on 20, 15, and 10 meters.  Performance on 40 meters is marginal, but you can work in the 7 Mhz region if you have to.  The antenna cost me nothing since I had the materials on hand.

Keeping the vertical alive

Because of my smallish back yard, most of my antennas have been verticals or loops strung under the house.  My trusty 40-meter vertical had been taking a beating from the rains and salt air over the past few months, so I decided it was time to restring the wire on the fiberglass mast and examine the feedlines and coax to the shack.  I'm glad I did a routine maintenance check on Sunday.  The coax to the shack from the 4:1 balun had been chewed by some kind of rodent, most likely a roof rat which can eat almost anything.  Since I was out of RG-8x, I pressed some RG-6 cable into service.  Fortunately, I had some "F" to UHF male adapters on hand, so the hook up was painless.  I got the fairly rare connectors from B & A Products, Co., P.O. Box 1376, Muldrow, Oklahoma, 74948.  The adapters work very well.  The Drake MN-4 handles the slight mismatch between 50 and 75-ohms without any trouble.  The 40-meter vertical with its associated tuned counterpoise is once again doing its job.  Still on the drawing board is the 20-meter vertical dipole, which should be erected in the next week or so.  

None of these antennas are anything special, but they do work.  As with all my vertical antennas, I can lower them when I'm not operating--a great convenience when it comes to nosey neighbors or protecting the antennas from lightening.  As the old saying goes, "so many antennas, so little time."  I trust that your weekend will be filled with interesting contacts...you might even hear me from the isolated Hamakua Coast on the lower side of 40-meters.  I always QSL...something I picked up as a novice amateur radio operator.  Have a good weekend.

Aloha es 73 de KH6JRM.