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 small cost.  Since I’m financially conservative by nature and now settling into a “semi-retired” state, expensive antenna projects will have to wait until the xyl and I move to our property in the Puna District (20 miles southwest of Hilo).  With that in mind, I spent most of this morning lowering my hastily made novice class dipole (as mentioned in the last post) and reusing the parts for the inverted “vee”.  I was able to attach two, 33-foot lengths of  #14 gauge  house wire to each side of the 450-ohm twin lead with an angle of about 120 degrees separating the wires.  I ran 50 feet of twin lead to a 4:1 balun attached to the garage.  The balun was attached to approximately 20 feet of RG-6 coax, which then ran to a Drake MN-4 ATU.  A short 3-foot jumper cable made from RG-6 connected the ATU to the old Swan 100 MX. 

The antenna works well between 40 and 10 meters.  The ATU is happy, the old Swan is happy, and I am happy.  In the original article by W1FGH, the cost of the antenna was around $4.  But that was back in 1998.  Nowadays, everything is more expensive.  Nonetheless, I was able to make this antenna out of materials I had in the shack and in the garage.  Since I’m a packrat, I had no trouble finding wire, connectors, rope for guy wires, cable, twin lead, and tools to finish the project.  And like my previous vertical antennas, I can lower the structure and its elements when I’m not using them.

For my modest station, this inverted “vee” provides plenty of contacts from this isolated chain of islands in the Central Pacific–even at qrp levels of 10 watts or less.  When the neighbors aren’t home, I run a little more power (around 50 watts).  The mast is painted a light green to match the local surroundings.  The antenna is barely noticeable from the street.

Building the inverted “vee” was lots of fun and it gave me plenty of exercise outdoors.  Antenna and kit building are some of the areas we amateur radio operators can explore without spending too much money.  My favorite radio store is the nearest Home Depot or Ace Hardware Store.  Of course, there are some specialized parts that must be ordered from mainland sources (Mouser, Digikey, Jamco, and others), but, generally, a well-supplied junk box will give you most of the parts you need for simple antenna projects.  Besides, one gets a sense of accomplishment and satisfaction from building something from “scratch”. 

That’s all for now.  A few household chores remain before I can fight the qrp on the lower edge of 40 meters.

Have a good weekend!

Aloha es 73 de KH6JRM–BK29jx15

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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, and worth the effort.  I suppose a commercially made antenna would have solved many of my signal problems as a new novice, but I enjoy getting my hands dirty, measuring out the wire, strapping pvc pipe together, and seeing if the antenna project will endure Hawaii’s sun, rain, and volcanic smog (vog).  Those three elements can destroy an antenna in a few short years.  In fact, the acid rain that falls here (caused by the active Kilauea Volcano) really damages the paint on most vehicles.  I’m constantly polishing my van to keep rust, soot, and corrosive materials off the vehicle.  It’s a continuous battle against the elements.  The same applies to antennas.  That’s why I keep my antennas simple.

Over the past few years, I’v found simple dipoles fed with 450 or 300 ohm twinlead seem to do the best as general purpose HF antennas.  I’ve been fortunate to have access to various lengths of schedule 40 pvc pipe which can be used to make 25-35-foot masts.  This lightweight material can be erected by one or two persons fairly easily.  Once the pvc and its attached antenna wire are suitably guyed, they will serve nicely for a couple of years before nature takes her revenge.

I usually don’t worry about the type of wire for the verticals I make.  Number 14-gauge house wire is abundant, as are smaller gauges such as 20, 22, and 24.  As long as the small wire is supported by and taped to the pvc mast, it will serve as a decent antenna.  Then all you have to do is attach a number of radials and you’re on the way to enjoying amateur radio at a fairly cheap price.  One can also use a mast to make an inverted “vee” which doesn’t require a radial system.  I’ve used both types of antennas on my small lot. 

As for coax, I’ve found RG-6 (the type cable companies use) and RG8x quite satisfactory for low power applications below 50 watts.  When I worked at a commercial radio station in Hilo, I was able to get various lengths of RG-6 from studio rebuilds.  I’ve used these various lengths to make patch cords and feedlines.  Even if you have to buy RG-6 from a hardware store (such as Home Depot or Ace Hardware), it’s a good bargain.  You can order adapters for the “F” connectors from a variety of cable distributors.  With an approximate impedance of 75 ohms, RG-6 shouldn’t be too difficult a match for your antenna tuner.  My Drake MN-4 seems to do alright with this cable.  For higher power levels, you may want to use RG-8 or RG-213.

My xyl is right–I’m a packrat when it comes to electronics.  I haven’t changed much since I was first licensed.  Only this time, I’m somewhat better organized.  At least all my wire, cable, parts, and tools are segregated by type and labled so I can find stuff quickly.  My garage is becoming a well-organized graveyard for leftover cable, wire, rigs, and reference material.  The ham who called his operating position a “shack” really hasn’t seen my place.  It’s what I call my overgrown “junk box.”  My poor xyl has given up trying to “reform” me.  At least I can fix most electronic stuff in the house.  I suppose I do have my uses.

So, as we face another beautiful weekend on Hawaii Island, it seems appropriate to rebuild the dipole antenna I first used as a novice.  There are two medium high trees in the back yard with just enough room to string up a dipole with 32-feet on each side–a little short for 40 meters, but the 450-ohm twin lead, a 4:1 balun, and the trusty Drake MN-4 should be able to handle my excursions on this band.  Who knows? I may just leave it up for awhile…at least until the neighbors start asking questions.  If that happens, up go the verticals again.

Until next time, enjoy the weekend and get on the air!

Aloha es 73 de KH6JRM–BK29jx15.

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 most about the story was the willingness of the older hams to admit their “on again, off again” relationship with amateur radio and how their mutual  interest in amateur radio lead to marriage and a life-long commitment to serve as mentors or elmers to a younger generation.  The two older operators come across as people you would want to know–people who have lived life and want to share their knowledge and even their fears with the upcoming ranks of newcomers.  The younger ham appears to be a normal, inquisitive 15-year old who isn’t afraid to ask questions and tackle the problems of his new hobby.

I suppose in many ways, Keith has rephrased the Golden Rule in an amateur radio context—treat people as you wish to be treated.  Many of us have had poor experiences with insensitive clubs and rude operators.  While that hasn’t stopped hams from progressing in the hobby, it surely has left a bad taste for new amateurs who want help and direction rather than criticism and “put downs”.  Some of us tend to foreget that we were once new and had the same uncertainties as the young amateur in the story.

As I approach the “event horizon” of my life, I tend to forget the bad experiences and concentrate on the present and even the future (if I live long enough).  I’ve learned to “turn the dial” and ignore those whose joy in life seems to be creating misery for themselves and others.  Life is too short to be consumed by some perceived wrong.  Change is inevitable–life moves on.

So, Don Keith tells a good story–one that could help you rekindle your love for amateur radio.

Aloha es 73 de KH6JRM–BK29jx15

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 limitations.  Unlike PSK31, you can’t enjoy conversation with JT65.  The exchanges are limited to call signs, signal reports, and grid squares–perfect for the DX chaser or moonbounce enthusiast.  Operators take turns on even and odd minutes, and it takes about 5 minutes to complete a contact.  Although I’ve not tried this mode, it sounds fascinating and doesn’t require a lot of power or a super efficient antenna.

Steve Ford, WB8IMY, also contributed another article called “RemoteShack RBC-212 Remote Station Controller.”  Ford describes how the device can allow hams in poor locations to operate remotely with a high speed computer connection.  When I was working at a commercial radio station in Hilo, Hawaii our engineers used a similar system to remotely monitor transmitter performance across Hawaii Island.  Now, it appears that Radio Shack has developed a device that can control your remote transmiter over the telephone, radio, or the Internet.  Ford says, “as long as you have a telephone, a transceiver with a DTMF keypad, or a laptop and Skype or similar software with DTMF capability, you can control your radio anywhere with RemoteShack.”  Although the unit is expensive (almost $575), it may provide a viable alternative for those unable to operate their transceiver from their home.

The May 2012 edition of “QST” also has a nice summary of the recent WRC-12 conference.  The results for amateur radio were positive–a new MF allocation of 472-479 kHz for the amateur service required a lot of work, years of research, and the coopertion of many governments. In the United States, the band won’t be released for amateur use until at least 2013.  The FCC will need some time to create the necessary rules and regulations for this portion of the spectrum.  None the less, this slice of the spectrum should spur experimentation in hardware, software, and antennas.  Apparently, Elecraft is already in the game, with the K3 capable of generating weak signals in that band.  Look for more equipment and applications in the year ahead.

Despite amateur radio’s success in WRC-12, there are many challenges before us.  WRC-15 preparation is already underway with several agenda items making the “hot list.”  These include mobile broadband allocations, possible expansion of amateur service in the 5 MHz (60 meter) band, additional fixed-satellite allocations for Region 1 between 10 and 17 GHz, and a possible primary allocation to the radio-location service for automobile applications at 77.5 to 78.0 GHz.  As amateur radio operators, we must keep abreast of developments that would affect our use of the limited electromagnetic spectrum.  One way to keep informed is to subscribe to the journal of your country’s amateur radio community and to follow sites such as QRZ.com and eham.net.  Vigilance, knowledge, and public service will keep amateur radio a vital component of our society.

Have a good weekend!

Aloha es 73 de KH6JRM, Laupahoehoe, Hawaii, BK29jx15

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 garage, and a B & W window ledge apartment antenna for the HF system.  I acquired the B & W antenna back in the mid-80s and have used it a few times for impromptu operations at the qth or at the nearest public park bench.  MFJ markets a close relative of the old B & W known as the MFJ-1622, complete with an air wound loading coil, telescoping 5 1/2-foot radiator, choke balun, counterpoise wire, a length of RG-58 coax, and a safety rope.  All of these components take up little room in the van and can be stored in a large plastic tub behind the passenger seats.

This weekend I tried out my older version of the MFJ system and it worked well enough on 40 and 20 meters to make this part of my emergency mobile and qth standby station.  Other than the cost of the original B & W apartment antenna, I was out very little.  The MFJ -1622 costs $99.95 in the MFJ 2012 Ham Catalog.  MFJ has a few other portable antennas you may want to consider for standby use.  My emergency mobile HF works and will be kept in the van for general operating or for emergency use.

If you don’t have a standby rig for emergency uses, you may want to consider the ICOM-703, SGC-2020, any rig from the Elecraft series, or even Yaesu and Kenwood rigs that were designed for qrp use.  Power can be supplied from a golf cart battery, a trowling fishing battery, or any other deep-cycle battery.  Vehicle batteries can be used, but they weren’t designed for this purpose and performance may vary.  The only thing I’m lacking now is a compact solar cell array to keep the deep cycle battery charged.  Presently, I operate from the deep cycle battery about once a week and keep the system charged with a trickle charger.  My main station uses a deep cycle marine battery and I keep that charged on a trickle charger as well.  The old Swan 100 MX can run for a day or two at qrp levels (10 watts SSB or CW) before voltage drops below 13 volts.  Of course, your mileage may vary, depending on the type of rig and power level you use.  Some of the earlier Ten-Tec rigs, such as the 509, century 21, or even the Argosy I, II can be pressed into service.  There are several low power Heathkit transceivers such as the HW-7, HW-8, and HW-9 that can be used if cw is your preferred mode of operation.  For the do-it-yourself enthusiast, there are many good kits available in a variety of configurations.

The important thing is to have a backup rig in case your main rig is down or you lose power at your qth.  I’ve also stashed a 100-foot spool of #22 gauge wire, insulators, small tools, connectors, and 50-feet of RG-6 coax (with connectors) in the emergency tub containing the HF station.  All of these items fit neatly in the back of my van.

One never knows what will happen these days and an emergency HF/VHF station in your vehicle could save your life some day.

Have a good weekend!

Aloha es 73 de KH6JRM–BK29jx15

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


One of the joys in making your own antennas is to discover what others have done in similar circumstances.  A visit to the antenna forums on QRZ.com and eham.net can give you a lot of useful information, particularly if you must operate from a deed-restricted area or from a small backyard as I do.  I am amazed at some of the clever antenna designs that my fellow amateur radio operators have used to get around HOAs, CC&Rs, and lack of space.

Another good source of ideas for those of us in space-restricted areas are books and articles dealing with small antennas, stealth antennas, and concealed opertions of various sorts.  Although most of us can get by with the antenna books published by the RSGB, ARRL, and CQ Communications, there are a few sources I would recommend from personal experience.

The first book on my list would be “The Short Vertical Antenna and Ground Radial” by Jerry Sevick (SK), W2FMI.  This small volume offers several useful and effective designs for the small backyard.  Presently, I am using one of Sevick’s vertical helix antennas near my wooden garage.  I wound 33 feet of #14 gauge wire on a 10-foot pvc pipe, stuck it on a 4-foot stake, attached eight, 10-foot radials, and ran some 450-ohm balanced line to a 4:1 balun, which was connected by a short length of RG-6 coax to the trusty Drake MN-4.  Apparently, by winding a half-wave’s worth of wire around the pvc mast in the form of a helix, it approximates a regular quarter wave antenna.  I added some top loading with a 10 inch pie tin (aluminum) and I was in business.  The bandwidth is quite narrow, but the Drake MN-4 can make the antenna cover most of 40-meters.  I can use the helix from 40 to 10 meters if I have to.  The tuning is sharp but manageable.  I suspect the antenna has some pronounced ground loses, but it does get out and I do make contacts beyond Hawaii with RST reports ranging from 539 to 579 (cw).  Not great…but this antenna does allow you to get on the air.  One of the benefits of this homebrew skyhook is its ability to blend in with the trees bordering my lot.  You can’t see the antenna from the street.  I run anywhere from 05 to 30 watts with this antenna without any rf “bite” in the shack.  I think I will keep this antenna as an emergency backup or for portable operation.  I can divide the vertical helix into two, 5-foot sections and pack the antenna wire and radials in a small bag.

Another book I have found valuable is “HF Antennas For All Locations” by Les Moxon (SK), G6XN.  Although the book may be a bit complex for those of us non-technical types, it contains enough examples of simple antennas to keep us busy for years.  Moxon writes well and he supports all of his designs with the appropriate drawings and mathematical analysis.

And, of course, there are those antennas that I just build and test for the sheer joy of seeing if they work.  As you may suspect, some of my great ideas have been less than spectacular, but that’s how we learn.  Antennas are the one area where every amateur can do something on his or her own initiative.  Half the fun of building antennas is getting parts locally and modifying well-known designs to fit your particular situation.  Over the past several decades, hardware and home improvement stores have given me most of the parts required for my simple backyard antennas.  As for coax and wire, I’ve become friendly with cable installers and former radio station associates, who often supply me with cable end runs and various lengths of wire from studio rebuilds.  I’ve learned to appreciate RG-6, since most of these cables are available free or at minimum cost from installers.  With the proper connectors, RG-6 is suitable for antenna feed lines, patch cords, and impedance transformers.  As for antenna wire, I’ve used everything from #22 gauge hookup wire to “zip cord” used for wiring lamps and electrical appliances.  I wouldn’t recommend “zip cord” for feedlines because of line losses, but it does make for good radiating elements in a dipole.  The plastic insulation on the cord provides some protection from the elements.

The important thing is to use your imagination and locally obtainable materials to “roll your own” antennas.  Your designs will improve as you gain experience.  Along with some antenna design software and your PC, you can quickly fashion an antenna that will give you the performance you require at a minimum cost.   Besides, you will have the pride in knowing you built it yourself without “breaking the bank.”

That’s about all for today as I prepare to return to my teaching duties on Friday.  Have a good weekend and build an antenna that you can call your own.

Aloha es 73 de KH6JRM–BK29jx15

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


While I was searching through some boxed electronic parts in the garage this afternoon, I discovered an old Hustler mobile mast, bumper mount, shock spring, and coils for 40 meters, 20 meters, and 15 meters.  When I first became an amateur radio operator back in 1977, I used the Hustler system on my then almost new 1976 Toyota Corolla.  That was a very small vehicle and I had to be creative in placing an old Swan 260 Cygnet transceiver in front of the passenger’s seat.  Fortunately, the Toyota had a metal bumper which was able to hold the mobile mount and antenna.  After I bonded all the body and engine bolts with copper braid and installed special spark plugs, the system became a cumbersome, but successful mobile installation.  When I moved to my present location in Laupahoehoe and bought a new car, I cleaned and stored the old mobile antenna in the garage and gave the old Swan transceiver to a new ham who didn’t have a rig.  Since that time, I haven’t done much in the way of mobile operating, except for 2 meters.  Remembering those early years, I’m beginning to get the urge to go HF mobile again.  Before I do anything, I’m going to check out Alan Applegate’s mobile installation site and see if I can do the work myself without damaging my new Honda Odyssey van.  I’m reluctant to punch holes in the roof for a mobile antenna.  Currently, I’m using a mag mount with a 2-meter rig in the van.  I’ll have to give this idea some thought.

Anyway, the discovery of my long-lost mobile antenna got me thinking about how I could use the antenna to complement my modest “antenna farm” on my small lot.  I quickly attached the antenna to the metal roof of my garage and ran some RG-6 coax to the Drake MN-4.  I turned on the Swan 100 MX to see if the old antenna was worth saving.  I was using the 40 meter coil.  Wonder of wonders!  The old antenna showed a SWR of 1.7 to 1 after I adjusted the MN-4.  I enjoyed a few cw contacts for about a half hour.  Apparently, the metal roof of my garage was providing an acceptable ground for the old Hustler system.  After running the same test on 20 meters, I was convinced that, with a little more work, I could use this mobile antenna as an emergency backup should the need arise.  Of course, this antenna was a fairly crude arrangement and would not be a stellar performer in any kind of contest, but it did work.  So, if you have an old mobile antenna stashed away, you may want to use it if you can’t get any other antenna up in the air.

I hope your Easter holiday was spent with your friends and family.  It seems as if our modern world is moving so fast these days that we sometimes forget those things we cherish most.  It’s good to step back once in awhile and just enjoy the simple beauty of life. 

Have a good week and may your signal meet mine.

Aloha es 73 de KH6JRM–BK29jx15

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