Friday, March 28, 2014

Simple Ham Radio Antennas: The Ghost of Antennas Past, part 2. Post #268

The Novice Inverted Vee Antenna

Moving to a new QTH can be a lengthy process, especially when you're still working part time and must do all of the transporting yourself.  But in this drawn out activity, you have a chance to find things you were once thought lost forever.

Such was the case this past Wednesday, when a state holiday gave me and my xyl a chance to move some more "stuff" from our rental house to our permanent location in the Puna District of Hawaii Island.

Once most of the small objects, such as books, records, clothing, entertainment equipment, and, of course, amateur radio equipment is placed in their new surroundings, we can hire a commercial mover for the larger items, including beds, various pieces of furniture, and heavier items.  We'll probably take a few more months to get things everything squared away.  After all, both of us are supposed to be "retired".  We both teach school, so retirement is but another word to add to things of yesteryear.  With the cost of living rising ever higher, work becomes a life-long activity.  I don't mind, as long as we both keep active and enjoy our hobbies, including amateur radio.

During our last transport activity, I uncovered a complete set of logs and antenna notes covering the years 1977 to 1980--the years I was a novice, technician, and general class licensee.  I later became an advanced and extra class licensee, but that's a tall story for another time.

It was interesting to see what kind of antennas and equipment I used then.  The rig in those days was a slightly used and very forgiving Heathkit HW-101, a J-38 key, and a Drake MN-4 antenna "tuner".  The HW-101 was later given to a new ham.  The key and Drake MN-4 are still with me.  In those those three exciting years, I worked a lot of DX with some very simple antennas.  Thankfully, I kept the diagrams and associated measurements of those "skyhooks" in a series of school composition books which I filed with my old operating logs.  I still keep logs and antenna pages, but nothing beats re-examining the efforts of the past.

One of my favorite novice antennas was the inverted vee or drooping dipole.  All I needed was one tall mast, two antenna elements cut to my preferred frequency, a center dipole connector, a 75-foot/22.86 meters length of RG-58 with UHF connectors, my trusty Drake MN-4 ATU, and the much repaired HW-101.  When I added a low pass filter and the Heathkit Dummy Load (which I still have), I had a simple, functional amateur radio station.

I decided to follow my original plans and build a 40-meter inverted vee cut to my favorite 40-meter frequency of 7.125 MHz.  With a little nudging from the Drake MN-4 ATU, I could get acceptable performance on 15 meters, using the third harmonic of the 40 meter frequency.  The swr would be a little high because the third harmonic would fall just outside of my permitted 15 meter privileges.  The antenna would be modified later by extending the length of the original 40-meter elements so the resonant frequency would be near 7.088 MHz (the frequency of the Hawaii Afternoon Net).  Using the third harmonic of this frequency would put me near 21.264 MHz--just right for SSB operations in the 15-meter band.

Despite this limitation, I decided to build the antenna as a replica of my original 40-meter inverted vee.

MATERIALS:

One MFJ telescoping fiberglass mast measuring 33-feet/10.06 meters long.

One Budwig HQ-1 center coax connector.

Two antenna elements cut from #14 AWG house wire.  According to the general formula 468/f (MHz)=L (feet) and a design frequency of 7.125 MHz, each segment of the dipole would measure 32.84 feet (32 feet, 10 inches)/10.01 meters.  I probably should have allowed some extra length for swr adjustment, but, following my original plans, I didn't.  The Drake MN-4 would take care of the small mismatch in the line.

Seventy-five feet/22.86 meters of new Radio Shack RG-58 coaxial cable with UHF connectors.  I now use a better grade of coax, preferring RG-8X or RG-8 from Belden and other cable manufacturers.  This is another case of "live and learn."

Two 5-foot (1.52 meters) wooden fence posts to support the ends of the inverted vee.

One 5-foot (1.52 meters) wooden support stake for the fiberglass mast.

Two ceramic insulators to isolate the antenna elements from the wooden posts.

A few short length of nylon rope to tie off the antenna elements to the posts.

Basic tools, nylon ties, vinyl electrical tape.

Shack equipment, including a transceiver, low pass filter, dummy load, and the Drake MN-4 ATU.  Since I didn't have my original HW-101, I used my venerable Swan-100 MX transceiver, vintage 1983.

ASSEMBLY:

The antenna was built on the ground.

I then cut the antenna elements to length, soldered each element to the Budwig HQ-1 center coax connector, and attached a ceramic insulator to each free end of the antenna elements.

Before I attached the coax feed line to the center connector, I made a "choke balun" out of the RG-58 feed line near the center connector.  The balun consisted of a 6 turn, 8 inch/20.32 cm diameter hand wound coil secured with vinyl electrical tape.

I attached the coax to the center connector and ran the feed line down the length of the extended 33-ft/10.06 mast.  The coax was secured to the mast by nylon ties.  All exposed antenna connections were covered by several layers of vinyl electrical tape.

I secured the center connector to the top of the fiberglass mast with nylon ties and vinyl electrical tape.

I then hoisted the mast onto the wooden support stake, led the antenna elements at an approximate 45-degree angle from the apex of the mast, tied off the antenna segments to the pre-positioned wooden posts, and adjusted the antenna for a uniform and balanced appearance.

I led the remaining length of the coax to the patch panel in the shack window.  A short length of RG-58 (6-ft/1.82 meters) went to the Drake MN-4 ATU.  Small patch cords made from RG-58 coax I had in the junk box connected the Swan-100 MX, dummy load, and low- pass filter to the Drake MN-4.

RESULTS:

With the Drake MN-4 ATU in line, I was able to keep swr at 1.3 to 1 across the entire 40-meter band.  Tuning was bit touchy on 15 meters, but I was able to get an swr of 1.5 to 1 on most of the band.  Tuning on 20-meters and 10-meters was a bit more tedious, owing to the high swr present on those bands.  I decided, like in the past, not to push the old Drake MN-4 too far with a severe mismatch.  But for its intended purpose of getting a new novice on the air using 40-  and 15-meters, the antenna works.  Following my past operating procedures, I ran no more than 50 watts from the old Swan-100 MX transceiver.  The finals are a bit "long in the tooth" and I didn't want to begin a search for replacements.

During the course of several hours of operating  from early afternoon to mid-evening, I made many satisfying contacts on 40-meters CW and 15-meters SSB.  I'll play with this antenna for awhile and then I will carefully take it down, repack it, and save if for portable or emergency use.  This was a fun way to connect to my "novice" days as a newly licensed  amateur radio operator.

REFERENCES:

http://www.arrl.org/your-first-antenna.

http://www.arrl.org/file/Technology/tis/info/pdf/0683033.pdf.

http://www.iw5edi.com/ham-radio/?10-meter-dipole, 140.

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Thanks for joining us today!

Aloha es 73 de Russ (KH6JRM).

BK29jx15--along the beautiful Hamakua Coast of Hawaii Island.


Monday, March 24, 2014

Simple Ham Radio Antennas: The Ghost of Antennas Past. Post #267

Humans tend to collect things.  Amateur radio operators are no exception.  In my 37 years as a licensed amateur radio operator, I've collected enough electronics-related material to fill most of my garage/radio shack at my new home in the Puna District.  Fortunately, I've managed to keep things organized, more or less, with plastic storage bins and some old filing cabinets.

During the ongoing moving process, I discovered antennas, books, logs, and parts once given up for lost.  Such was the case Monday, 17 March 2014, when I reorganizing some of the material brought to the new QTH.  I found several well-sealed boxes containing some of my successful antenna projects.  All the antennas were dipoles built during my over three decades of "warming the ether" with a variety of old tube rigs long since gone to to the great capacitor in the sky.  After I finished using these antennas, I had the foresight to clean and store them for future use.  Also along the back wall was my first HF mobile antenna--a Hustler antenna system with the old 54 inch/137.16 cm foldover mobile mast, coils for 40, 20, and 15 meters, a bumper mount, and 12-foot/3.65 meters lengths of  RG-58 coax with "pigtails" for attaching to the bumper mount and mast section.  That antenna system rode on my old 1974 Mercury Comet sedan.  Unlike today's cars, that vehicle had a real metal bumper to attach the mount and shock spring.  Back in 1977 when I was first licensed, that mobile system spoke to the world with a venerable Swan-260 Cygnet.  Ah, those were the days!

What could I do with the old Hustler antenna system?  I didn't want to throw it away because the metal and coils remained in excellent condition. I already had a magnetic mount "Hamstick" HF mobile antenna system for my Odyessey van, so the old Hustler antenna had to find a new role on my "antenna farm."

After deliberating a few moments, I decided to convert the old Hustler antenna system to an emergency antenna for my QTH.

Fortunately, I had a 6-foot/1.82 meters tall  chain link fence running down my south property line for a distance of approximately 50-feet/15.24 meters.  I would use the fence as a support for the bumper mount and as part of a ground radial system for the mobile whip.  Once I secured the bumper mount to the fence with the 54 inch/137.16 cm mast and the appropriate coil and tip, I would connect the 12-foot/3.65 meter coax with the pigtails to the vertical mobile whip, with the center wire going to the metal mast and the braided shield  being attached to the metal fence with a small battery clip.  I also attached three gently sloping radials measuring 33-feet/10.06 meters each to the braid as well.

I next attached 50-feet/15.24 meters of RG-8X coax with UHF connectors to the shorter piece of RG-58 coax affixed to the antenna.  The RG-8X coax was then connected to the patch panel in the shack window.

A short piece of RG-8X coax (6-feet/1.82 metes) ran from the patch panel to the Drake MN-4 ATU.  Short pieces of RG-8X coax interconnected the dummy load, low pass filter,and the venerable Swan-100 MX to the Drake MN-4.

By adjusting the wire tip at the end of each coil, I was able to get a SWR of 1.7 to 1 on 40, 20, and 15 meters without the ATU.  With the Drake MN-4 in the antenna system, I was able to get a SWR of 1.2 to 1 on those above mentioned bands.

Performance was good, considering the compromise radial system and the low height of the mobile antenna.  I was able to make local, statewide, and some mainland DX contacts during the late afternoon.  Most of my SSB reports averaged between 54 and 57, with CW responses varying between 559 and 599.  Not too impressive, but I did get contacts.

When the sun came out late that afternoon, I set up a card table in my front yard, positioned the old Swan-100 MX, Drake MN-4, the dummy load, and the low pass filter on the temporary support.  I dragged out the solar-charged deep cycle marine battery and enjoyed a few pleasant hours operating outdoors.

When I was done for the day, I just disconnected the temporary radial system (including the attachment to the chain link fence), removed the bumper mount from the chain link fence, and stored the mast and coils in the garage for another day.

I was glad to see the old mobile system get a new lease on life.  No sense throwing out something that works.

And, yes, I'm trying out all of my old dipole antennas.  They still work very well.  They are "ghosts" of my early ham past which continue to "haunt" me today.  Some "spooks" are worth keeping.

Thanks for joining us today!.  You can join our blog community with a free email subscription or by tapping into our RSS feed.

Aloha es 73 de Russ (KH6JRM).

BK29jx15--along the beautiful Hamakua Coast of Hawaii Island.
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Tuesday, March 18, 2014

Simple Ham Radio Antennas: The "Fencetenna". Post #266

Building wire antennas is one of the few amateur radio activities that remains fairly inexpensive.  Your nearest hardware store or home improvement outlet is chocked full of wire, connectors, pvc pipe, copper tubing, and basic tools to launch your antenna building efforts.

Whether you make simple dipoles, inverted vees, loops, or even directional vertical arrays, the satisfaction of having built something that links you to your fellow amateurs around the world is beyond compare.  If the antenna doesn't meet your expectations, you can salvage most of your material and try again.  It's all part of a continuing educational experience that can last a lifetime.  Add to this mix a few simple transceiver kits or accessories and you have something that will be your faithful radio companion for many years.

I approach my antenna "adventures" with that sort of mindset, and I'm always on the lookout for intriguing antenna ideas that I can modify for my own use.

Such was the case last week Friday after the Laupahoehoe Community Public Charter School took its annual spring break.  My xyl and I planned a brief visit to our new property in the Puna District to continue work on remodeling our permanent home.  There would also be plenty of time to search for new antenna locations once the building chores got done.  Fortunately, our property is surrounded by a semi-tropical forest of ohia, hale koa, and norfolk pine trees which range from 20 to 60 feet/6.09 to 18.29 meters high. This is a perfect environment for antenna experimentation.  I already have found a place for a multiband inverted vee, an 80-10 meter doublet, and an 80 meter loop antenna.  All of these antennas are fed with 450 ohm ladder line connected to a 4:1 current balun.  A short length of RG-8X ties the system to my trusty Drake MN-4 ATU or the spare MFJ 941-E Versa Tuner II.

A curious feature runs along the north property line of my new home.  The previous owner had erected a 150 foot/45.73 meter, 6 foot/1.82 meters tall redwood fence to divide the property from the nearby forest area.  Why not use these fence to support a new NVIS (near vertical incident skywayve) antenna?  I had plenty of hookup wire (#22 AWG) in the shack, a few ceramic insulators, 75 feet/22.86 meters of RG-8X coaxial cable with UHF connectors, and an old, but serviceable 1:1 current balun.  So, another antenna scheme was hatched.

Earlier this month, I remembered an article by Dave Land (KD5FX) on the "Fencetenna", an all band antenna supported on a wooden privacy fence which was invisible to neighbors and enforcers of HOA and CC&R antenna rules.  This would make a near perfect stealth antenna.  I decided to modify Dave's design and build my own version of the "Fencetenna."

MATERIALS:

The antenna is simplicity itself.  Following Dave's guidelines, I assembled the following items:

One 1:1 current balun.

A convenient length of coaxial cable with UHF connectors.  The fence was approximately 50 feet/15.24 meters from the shack, so 75 feet/22.86 meters of RG-8X would be sufficient for the feed line.

Two non-resonant antenna elements, measuring 70 feet/21.34 meters each.  #22 AWG hookup wire was used for the antenna elements.

Two ceramic insulators and nylon rope to tie off the antenna segments.

Some push pins.

Short pieces of nylon rope to secure the antenna segments to the fence.

Nylon ties to secure antenna elements, the balun, and a portion of the coaxial feed line to the fence.

Various tools, including a soldering gun, wire clippers, pliers, knife, and sandpaper.

Shack equipment, including a Drake MN-4 ATU and a MFJ 941-E Versa tuner II.

Ten-Tec Argosy II, Swan 100-MX, and a Kenwood TS-520.

Heathkit Dummy load and a low pass filter.

ASSEMBLY:

I built the antenna in the garage.

Each antenna segment was soldered to its respective tab on the 1:1 current balun.  All connections were covered by several layers of vinyl electrical tape.

A ceramic insulator was attached to each end of each antenna element.

I positioned the balun horizontally across the top of the fence and secured it to the fence with several nylon ties.

I ran one antenna segment along the top of the fence and secured the attached end insulator with nylon rope and push pins to the top of the fence.

I ran the remaining antenna segment vertically down from the balun to the bottom of the fence, a distance of approximately 6 feet/1.82 meters.  The vertical portion was secured with nylon ties and a push pin.

Once the vertical section was secured, I ran the remaining length of the antenna (64 feet/19.51 meters) along the bottom of the fence and secured the attached end insulator with nylon rope and push pins to the lower portion of the fence.  The bottom element was approximately 1 inch (2.54 cm) above ground.

I then attached the RG-8X coaxial cable to the horizontally placed balun and ran the cable to a point approximately 10 feet/3.04 meter along the top of the fence.  The cable was secured to the fence at this point by nylon ties.

The cable was run to a plastic hook on the garage and then to the patch panel in the shack window.  A 6-foot/1.82 meter section of RG-8X ran from the patch panel to the Drake MN-4 and later to the MFJ 941-E Versa Tuner II.  Small coaxial patch cords connected the Ten Tec Argosy II to the Drake MN-4 ATU, a low pass filter, and the Heathkit Dummy Load.

TESTING:

With the help of the Drake MN-4 and the MFJ 941-E Versa Tuner II, I was able to get a SWR of 1.5 to 1 or lower on 80, 40, 20, 30, 15, and 10 meters.  Performance was excellent for local and regional contacts. Better DX coverage can be obtained with a dipole or with a vertical antenna connected to a proper ground radial system.  But, for a simple, stealthy antenna, the "Fencetenna" is worth a try for those of you confronted with HOA and CC&R restrictions.  Remember, out of sight means out of mind.

Listed below are some additional stealth antenna sources you may find useful:

http://www.bvac.org/pdf/HF_Antennas_by_KD5FX.

http://www.swharden.com/blog/2010-2-07-simple-diy-stealth-apartment-antenna-for-20m-and-40m/.

http://www.g4ilo.com/stealth.html.

http://www.dxzone.com/catalog/Antennas/Stealth/.

Thanks for joining us today!  You can follow our blog community with a free e-mail subscription or by tapping into the blog RSS feed.

Aloha es 73 de Russ (KH6JRM).

BK29jx15--along the beautiful Hamakua Coast of Hawaii Island.
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Thursday, March 13, 2014

Simple Ham Radio Antennas: "The Poor Man's Beverage" Antenna. Post #265

Like many amateur radio operators, I've collected many boxes of electronic parts, various lengths of coaxial cable, and assorted rigs over the past 38 years.  I suppose my "shack" is testament to my "pack rat" tendencies.  I rationalize this collective habit by saying all of this material will become useful some day.  That some day was Thursday, 13 March 2014.  I had several lengths of RG-58 coaxial cable that had seen better days.  The assorted 100-ft/30.48 meters and 50-ft/15.24 meters lengths were gathering dust in the corner of the garage serving as the storeroom for my radio room.  The connectors were in good shape and the vinyl covering was intact, although a bit grey from sun exposure.  I wanted to find a use for the old cable ,now that it had been "retired" from active service.

Why not use the old coax as a low noise receiving antenna for 80 meters, which was a very noisy band even in my remodeled home in the Puna District of Hawaii Island?  About a week ago, I read several articles on what some hams call "The Poor Man's Beverage Antenna", using a length of coax between 1/2 and 1 wavelength long for the band of your choice.  The term refers loosely to the wave antenna developed by H.H. Beverage, Chester Rice, and E.W. Kellogg at the General Electric Company in the early 1920s.  Beverage published his findings in the November 1922 "QST" magazine.

Modern versions of this classic receiving antenna have been used by amateur radio operators to operate on 160 and 80 meters, bands frequently "blessed" by noise and static.

Using modified designs from GM4ULS, VE3NH, K9AY, and W9XT, I quickly made a "Poor Man's Beverage Antenna" for 80 meters.  The antenna works surprisingly well and cuts background static/ noise below that which I usually get when I use my inverted vee or doublet.

ASSEMBLY:

I designed the receive antenna for a frequency of 3.500 MHz.  Using the basic dipole formula 468/f (MHz)=L (feet) and multiplying that answer by 2 to get a full wavelength antenna for that frequency, I came up with a length of 267.42-ft/81.53 meters.  Fortunately, I had 3, 100-ft/30.48 meters of old RG-58 coaxial cable in storage.  I joined 2, 100-ft/30.48 meter lengths of coax with UHF female connectors. I then added 67.4 ft/20.54 meters of coax from another 100-ft/30.48 meter roll of RG-58 with the remaining  UHF female connector.

At the far end of the coax, I soldered the braid and tip together and covered that area with vinyl electrical tape.  Some antenna experts suggest that the far end be terminated in a resistor network to match the impedance of the coax.  Values range from 220 to 600 ohms, capable of 1 watt power dissapation.  I chose to leave the resistor network out of the system.

This antenna requires the use of an antenna transmatch or ATU.

At the ATU end of the RG-58 coax, GM4ULS recommends you "leave a gap of about an eighth of an inch in the braid.  The braid should therefore be isolated from the chassis of the ATU."  Once I did that, I connected the RG-58 to my trusty Drake MN-4 transmatch and "snaked" the coax through the shack window and laid the cable on the ground.  I ran the cable on the surface of the ground through the property's forest to a point approximately 260-ft/79.26 meters from the shack window.

I aimed the "ground-mounted" antenna towards the U.S. mainland (approximately 50 degrees from my Puna District QTH).

INITIAL RESULTS:

For the first time in many years, I was able to enjoy 80 meter signals.  Although there is some signal loss in the antenna, background noise, static crashes, and power line rfi are greatly reduced.

I will continue to use my inverted vee and doublet to transmit on 80 meters, but I will soon make a switch box to shift reception to the "Poor Man's Beverage Antenna."  On 80 meters, this antenna is definitely quieter than my other antennas.  As a bonus, the ground-mounted antenna excels as a broadcast band receive antenna.

So, don't throw away your old coax.  Make a low noise antenna instead.

REFERENCES:

http://www.gm4uls.wordpress.com/2012/06/27/the-snake-antenna.
http://www.lists.contesting.com/_cq_contest/1993-01/msg00019.html.
http://www.aytechnologies.com/TechData/ShortBev.htm.
http://isp.ca/ve3nh/snake.htm.
http://www.kc7nod.20m.com/snake.htm.
http://www.nrcdxas.org/articles/Beverage0182pdf.

You can follow our blog community with a free email subscription or by tapping into the blog RSS feed.

Thanks for joining us today!

Aloha es 73 de Russ (KH6JRM).

BK29jx15--along the beautiful Hamakua Coast of Hawaii Island.
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Thursday, March 6, 2014

Simple Ham Radio Antennas: Sam's "James Bond" Antenna. Post #264

Whenever I get a day off from my substitute teaching duties, I try to attend meetings of the Hawaii QRP Club at the Hilo, Hawaii Jack In The Box Restaurant.  The meetings usually last from 0600 to 0900 local time and cover a variety of topics, from antennas to homebrewed equipment.  Attendance varies from to 2 to 7 or 8 persons, depending on who's working or free for the day.  Dean Manley (KH6B) usually brings some of his antenna notebooks and his vast storehouse of experience as a radio broadcast engineer to the meetings.  There's always something interesting or new at these gatherings.

Recently, some of us have been discussing homebrewed antennas that can be operated from areas restricted by HOAs, CC&Rs, or just plain lack of space.  One of the most intriguing antenna ideas came from the late Sam Kumukahi (KH6AFS), who, during the 1990s, used what he called a "James Bond" antenna with excellent results for local and occasional DX contacts.  At the 27 Februrary 2014 meeting, Dean gave me a description of this simple, effective antenna which can be used at home or in a portable situation.  The information below was given to me by Dean as a one-page handout.

Sam's "James Bond" Antenna (excerpts):

Sam Kumukahi, KH6AFS (SK), has been routinely using the "James Bond" antenna.  Questions still arise:  What is it?  How high do I install it?  How long do I make the feed line?  First of all, when "Uncle Sam" says he's using an antenna just 31 inches, it's true.  Believe him!  After a few skeptics doubted the performance, Sam loaned me his "James Bond" antenna.  I had a problem getting it to work in the shack, probably because of inadequate ground.

I moved the 31 inch antenna and my antenna tuning unit (ATU) to the garage floor. It barely fits between the car and my radio shack door.  It loaded up just fine.  I checked into the Hawaii Afternoon Net on 40 meters.  Yes ,(I) came back (with) many favorable reports.  Jack, KH6CC (SK), said I was just as strong as my dipole antenna!  Yes, now I'm a believer.

Picture your ATU in your shack or maybe on a picnic table in a park.  Take the mobile loading coil and its adjustable upper radiator.  I use a Hustler on  40 and 75 meters and a homebrew one for 160 meters.  Others have described fixed and portable operations with the entire mobile antenna.  This is different. Do NOT use the lower mast section.  Now attach the antenna to your ATU with the following connectors:

Feedthru/adapter, SO-239 to standard
3/8" thread, Radio Shack 21-961.
M-348 inline right-angle adapter, Radio Shack 278-199.
Double PL-259, Radio Shack 278-192.

Tune up is quite simple and straightforward:  (A).  adjust antenna above the loading coil for minimum SWR with the ATU switched "out."  (B).  Then, if SWR is not acceptable, switch in the ATU and adjust for minimum SWR.  (C).  Do not adjust the upper part of the antenna with ATU in the line as you may get misleading results.  Repeat A and B if necessary.

In the shack or elsewhere, you need a ground connection.  A good RF ground is quarter-wavelength coaxial cable.  I use a length of RG-58, one for each band:  23 feet for 40 meters, 42 feet for 75 meters, and 86 feet for 160 meters.  The coax center conductor only is connected to the ground post of the ATU.  The coax far end is (an) open circuit.

Dean Manley, KH6B., July 1995.

On Monday, 03 March 2014, I built a similar antenna using 40 meter , 20 meter, 15 meter, and 10 meter hustler mobile coils, their adjustable upper radiators, my trusty Drake MN-4 ATU, a homebrewed clamp, a 6-ft/1.82 meters length of RG-8X coax to connect the rig to the ATU, and a coax "counterpoise" bundle consisting of #18 AWG speaker wire measuring 33-ft/10.06 meters, 16.5-ft/5.03 meters, 11-ft/3.35 meter, and 8.23-ft/2.51 meters.  I attached the "counterpoise" bundle to the ground lug of the Drake MN-4 ATU.  The system seems to to work well, with only slight adjustments needed to the Drake MN-4.  I've received some good local reports on 40 meters and a few mainland U.S. contacts on 20 meters.  I made these contacts from an outdoor picnic table in my backyard.  The homebrewed clamp held the mobile coil and its adjustable upper radiator.  The rig was my old Ten-Tec Argosy II running around 10 watts both CW and SSB.  My power source was a deep cycle marine battery charged by solar cells.  I can fit the entire antenna system, the Ten-Tec Argosy II, the battery, Drake MN-4, and the clamp in the back of my Odyssey van.  The antenna works and would be ideal for emergency or portable use.

Thanks to Dean Manley for his advice and guidance in this project.

RESOURCES:

Personal discussion with Dean Manley on 27 February 2014, 0800 local time, at the Hilo Jack In The Box Restaurant.

MFJ makes a similar antenna called the MFJ-1622. The MFJ product is a variation of a design first marketed by B&W in the 1970s.  This antenna uses a tapped coil, a short telescoping radio antenna, a clamp, and a counterpoise wire.

Thanks for joining us today!  You can follow our blog community with a free email subscription or by tapping into our RSS feed.

Aloha es 73 de Russ (KH6JRM).

BK29jx15--along the beautiful Hamakua Coast of Hawaii Island.


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