Saturday, June 28, 2014

Simple Ham Radio Antennas. Improvised Field Day Antennas. Post #283.

The 2014 ARRL Field Day is just about history as more than 35,000 amateur radio operators transmitting from 2,500 emergency sites finish the last action-packed hours in this annual communications exercise designed to test communications capabilities during man-made or natural disasters.

I always enjoy Field Day activity, whether I spend a few hours operating, logging contacts, or even taking down the rapidly assembled antennas used for this part training exercise and part contest.

Over the past few years, I've used some impressive rigs (Elecraft K3) and neatly fashioned antennas, both commercial and homemade.  

This year was no exception.  As usual, I put in a few hours working for my former radio station at a "Moku O Hawaii" outrigger canoe regatta on Hilo Bay before I slipped briefly over to the Field Day site of the Big Island Amateur Radio Club at the Wailoa Visitor Center in Hilo.  I'm on a retainer to work various remote broadcasts and a few sporting events when regular on-air staff is on vacation.  This was one of those weekends.  I can't complain, since the radio station pays me well for a few hours work.

When I finished my announcing chores, I dropped into the Field Day site and remarked how simple and totally functional the arrangement was.  Most of the club members were spending the afternoon at the Hilo Walmart store manning an amateur radio display and inviting residents to visit our emergency radio site at the visitor center.

As is our club's practice, all of the equipment was borrowed from nearby hams and included mostly older gear and handmade antennas...just the sort of stuff I use around my shack.  While I thoroughly enjoy all of the modern equipment and well-machined towers and yagis, there's something intriguingly comfortable about older rigs and wire antennas.  Perhaps, I'm just cheap as I enter my "sunset" years.  Anyway, here's what the Big Island Amateur Radio Club was using around 1500W on Saturday, 28 June 2014:

Rigs:  The club was entered as "2A Pacific", but only one rig was available when I showed up.  The other rig was being shown at the Hilo Walmart Store as a promotional tool for amateur radio.  That rig will be part of the night-time operation on 40 meters.  The rig available during my all-too brief appearance was an old, but dependable Yaesu FT-857, vintage 2005 I believe.  The rig does alright for its age.  In addition to the stock microphone, a straight key and a keyer were available for the CW operator.

Power:  A small Honda generator and solar-charged deep cycle marine batteries.

Antennas:  Most of the afternoon was spent on 15 and 20 meters using one of our member's 20 meter hex beam.  The antenna worked well and many contacts were made.  A homemade, 2-element 10 meter beam was mounted on a pvc mast.  Ten meters was pretty dead at our location on Hawaii Island.  For 40 and 80 meters, the club used inverted vee antennas strung from the top of the mast supporting the 10 meter beam.  The pvc mast was approximately 40 feet/12.19 meters tall.  

Logging:  The club had access to a member's laptop which had a logging program installed (I didn't pay attention to the vendor).  A paper log was also maintained.

So, there it is...a very basic, simple emergency station that works with a minimum of fuss and expense.  I have to admit that it was fun operating this "no frills" station.  Sort of reminds me of my home station--older rigs (Ten-Tec Argosy II, Swan 100-MX, Kenwood TS-520) and easily erected and portable antennas (inverted vees, delta loops, and horizontal dipoles fed with ladder line).  Most of my antennas can be stored in my Odyssey van for emergency or portable use.  Nothing fancy...they just work.

I hope your Field Day was enjoyable, instructive, and challenging.

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Until next time,

Russ Roberts (KH6JRM)
BK29jx15--along the beautiful Hamakua Coast of Hawaii Island.

Thursday, June 19, 2014

Simple Ham Radio Antennas. An 80-10 Meter Field Day Inverted Vee Antenna. Post #282

ARRL Field Day is right around the proverbial corner--28 June to 29 June 2014, to be exact.  According to the ARRL, more than 35,000 amateur radio operators used 2,500 emergency-powered stations to get on the air in 2013.   A similar number is expected this year.

While many of our fellow amateurs will be heading to a Field Day site, there are a few of us, including yours truly, who will be operating under emergency conditions at home as 1E stations or as mobile stations as 1C.  For those of us home bound or forced by HOAs or CC & Rs to "hit the road" during Field Day, this national emergency communications exercise can be just as much fun and instructive as showing up a your club site.

Before I retired from the commercial broadcast business, I usually worked Saturdays and Sundays in the news room, doing play by play over the radio, or hosting remote broadcasts from shopping malls and craft fairs.  Great work and lots of crazy people, but I often missed a chance to work 2A Pacific from the Wailoa Visitor Center in Hilo.  So, I had to join the action as a home or mobile station running emergency power from solar-charged batteries or my trusty Honda generator.

Here's the station I used when work required me to miss operating with members of the Big Island Amateur Radio Club (Hawaii Island) on Field Day.

I wanted my emergency antenna to be simple, multi-banded (80-10 meters), easy to build and take down, and transportable in case I had to move my location.  I didn't want to worry about an extensive ground system.  That meant no ground-mounted verticals.  The configuration I chose for my 2010 Field Day antenna was an easily built 80 meter inverted vee fed with 450 ohm ladder line.  The ladder line would be connected to a 4:1 balun.  A length of 50 ohm coaxial cable (RG-8X) would run from the balun to my trusty Drake MN-4 antenna transmatch.  Short pieces of coax would interconnect the Drake MN-4 to my Ten-Tec Argosy II, a dummy load (Heathkit Cantenna), and a low pass filter.  

Overall, the improvised inverted vee performed well with the Argosy II running slightly under 50 watts output.

According to the plans I drew up four years ago, I needed the following materials:

One telescoping fiberglass mast to support the inverted vee.  I had a spare MFJ 33-foot/10.06 meters mast in the garage.

Six, 6-foot/1.82 meters wooden garden stakes.  One would support the mast, two would be tie off points for the inverted vee elements, and three stakes would support the 450 ohm ladder line/feed line off the ground until it terminated in the 4:1 current balun on the garage wall (the shack was in an enclosed two-car garage).

Fifty-feet/15.24 meters of 450 ohm ladder line (the feed line).

One ladder lock device to support the apex of the inverted vee.

Two ceramic insulators to secure the ends of each leg of the antenna.

One 6-ft/1.82 piece of RG-8X coaxial cable with UHF connectors

One 10-foot/3.04 meters piece of RG-8X coaxial cable with UHF connectors.

One W9INN 4:1 current balun.

Nylon rope to tie off the antenna elements to their wooden support stakes.

Station equipment, including basic tools, a Ten-Tec Argosy II transceiver, Drake MN-4 antenna transmatch (tuner), a Heathkit Cantenna dummy load, and a low pass filter.

A "counterpoise bundle" consisting of a 1/4 wavelength piece of wire for 80, 40, 20, 15, and 10 meters.  The counterpoise would be attached to the ground lug of the Drake MN-4.

Sufficient lengths of #14 AWG house wire to make each element of the inverted vee.  Using the general formula for a dipole, 468/f (MHz)=L (ft), and the lowest frequency of operation, 3.775 MHz, I cut two equal lengths of wire measuring 62-feet/18.90 meters each. This length was a rounding off of the calculated lengths of 61.98-feet/18.89 meters for each antenna leg.

ASSEMBLY:

The inverted vee was built on the ground.

I attached the top of the ladder-lock center connector to the small metal ring at the top of the fiberglass mast.  Each leg of the ladder line was run through its respective hole in the ladder lock.

I attached the pre-cut lengths of antenna wire (62-ft/18.90 metes) to the ladder line and soldered the connections.  Each connection was wrapped with several layers of vinyl electrical tape.

A ceramic insulator was attached to the free end (bottom portion) of each antenna segment.

I secured the ladder line to the fiberglass mast with nylon ties and ran the line to a point 5-feet/1.52 meters above the bottom of the mast.  This would keep the feed line off the ground until it reached the 4:1 balun on the garage wall.

I carefully hoisted the mast onto its support stake.  Each sloping antenna element was tied off to a wooden support stake with nylon rope.  The antenna was adjusted for a uniform, balanced shape. with the end of the drooping elements approximately 5-feet/1.52 meters off the ground.

The ladder line was strung out from the mast and was supported off the ground by three 6-foot/1.83 meters wooden stakes.

The ladder line was terminated at the W9INN 4:1 current balun.

A 6-foot/1.82 meter length of RG-8X with UHF connectors ran from the 4:1 balun to the patch panel in the window of the radio room.  A 10-foot/3.04 meters section of RG-8X with UHF connectors ran from the patch panel to the Drake MN-4 antenna transmatch (tuner).  Small pieces of RG-8X interconnected the Argosy II, low pass filter, and Heathkit Cantenna dummy load to the Drake MN-4.

Finally, a "counterpoise bundle" was connected to the ground lug of the Drake MN-4 antenna transmatch.

RESULTS:

With the Drake MN-4 in the antenna system, I was able to get a 1.1 to 1 SWR reading on 80, 40, 20, 15, and 10 meters.  Tuning below 3.700 MHz was a bit touchy, because the antenna was designed to be resonant at 3.775 MHz.  I made 50 or so contacts during my brief appearance (5 hours) on the air.  My best contacts were made on 40 and 20 meters.  

For a quickly made antenna, the inverted vee did an acceptable job. The antennas was easily built, cheap, and performed satisfactorily. This is the antenna I carry with me in my Honda Odyssey van. I've used this arrangement at public parks and beach areas around Hawaii Island.  With the Argosy II or Yaesu FT-7 packed in the back of the van, all I need is my solar- charged deep cycle marine battery to get on the air.

There's a good chance I'll be free for this year's edition of Field Day.  But, if I'm not, I can set up a portable station in just a few minutes.

Good luck in this special event!

Here are some additional Field Day antenna ideas:

http://www.g7fek.co.uk/software/G7FEK%20antenna.pdf.
(a multi-band "nested marconi" antenna).

http://www.hamuniverse.com/ae5jufielddayantenna.html.
(75-40-20 meter Field Day Antenna).

http://www.hamuniverse.com?kl7bobfielddayant.html.
(Field Day Antenna--5 bands with tuner).

http://www.eznec.com/Amateur/Articles/Field_Day_Special.pdf.
(Field Day Special-EZnec).  Original article published in "QST", June, 1987, pp.21-24, by Ray Lewallen, W7EL.

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 de Russ (KH6JRM)

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



Saturday, June 14, 2014

Hawaii County Mayor declares Amateur Radio Week in Hawaii County. Post #281.S

Source:  Hawaii Tribune-Herald, 14 June 2014.
Reporter:  Bob Schneider (AH6J), ARRL Pacific Section Manager.

In tribute to Hawaii Island hams who provide emergency communications for Hawaii County during times of natural or man-made disasters, Hawaii County Mayor Billy Kenoi has declared 23-29 June 2014 as "Amateur Radio Week" in Hawaii County.  Mayor Kenoi has urged the public to support the American Radio Relay League's (ARRL) Field Day events set for Saturday, 28 June 2014, when amateur radio club members will set up and demonstrate emergency communications equipment and skills.

In Hilo, the public is invited to activities hosted by the Big Island Amateur Radio Club (BIARC) from 8 a.m. to 5 p.m. at Walmart.  A Field Day station will be operational from 8 a.m. Saturday until 8 a.m. Sunday at the Wailoa Visitor Center in Hilo.  During that 24-hour period, local ham operators will contact other amateur radio operators across the Pacific and North America.


In his proclamation, Mayor Kenoi said, "Amateur Radio Week recognizes the miracle of radio transmissions over the airwaves and the accomplishments of amateur radio operators worldwide."  Kenoi added that "Amateur radio operators have provided countless hours of community services throughout the decades, and have also provided a bridge between people, societies and countries by creating friendship and the sharing of ideas."

Of the 717,201 amateur radio operators in the United States, there are 4,550 in the ARRL Pacific Section, which includes Hawaii, Guam, American Samoa, and the Commonwealth of the Northern Mariana Islands.

"Amateur Radio Week" will culminate with the ARRL Field Day operating event that simulates setting up a station in the field, and operating 24 hours to upgrade communications skills vital to emergency operations.  Amateur radio clubs throughout the United States, Canada, and the Pacific will set up transmitters to demonstrate emergency radio communications.

BIARC President Bill Hanson said people of all ages are invited to stop by the Hilo Walmart on Saturday, 28 June 2014, to join in hands-on demonstrations and many other communications activities.

At the Wailoa Visitor Center, amateur radio operators will be contacting other hams around the world through early Sunday morning.  Volunteers from Hawaii County Civil Defense, the American Red Cross, Community Emergency Response Teams, and volunteers planning a 30 August 2014 Puna Regional Emergency Preparedness Fair in Keaau will also attend events at the Hilo Walmart and at the Wailoa Visitor Center on Saturday.

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

Thanks for joining us today!

Aloha es 73 de Russ (KH6JRM).

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

Thursday, June 12, 2014

Simple Ham Radio Antennas. On the ground antennas. Post #280

Over the past few weeks, I've become fascinated with antennas mounted on or near the ground. I've even built a few, such as Mike Toia's (K3MT) "grasswire" antenna and a similar "earth" antenna from Australia.  A few months ago, I built a simple beverage antenna for my old Hallicrafters SX-62A receiver.  All or these wire antennas worked very well, especially for the AM broadcast band.

With a few modifications, these wires can be used as a separate receive antenna for amateur radio stations located in noisy or desert areas.  I've used vertical antennas for transmitting and low-mounted antennas for receiving.  

So, what are these ground hugging "long wires?"

According to articles published in the "NASWA Journal" for December 1992 and January 1993 by author Joseph Buch, these antennas mounted on, near, or slightly below ground level are called "wave" antennas because "they extract energy from the wave as it travels down the length of the wire and because its low height minimizes static induced by charged particles blowing in the air."  Buch adds that "Anyone who has tried to listen on a normal dipole antenna during a dry desert windstorm will appreciate this characteristic."  Experience gained from communications operations in Iraq and Afghanistan bears this out.

These antennas include one of the earliest and simplest of receiving antennas--the beverage--invented by a team led by Harold H. Beverage in 1922.  His experiments were republished in the January 1982 issue of "QST."  Basically, " The beverage antenna is a wire near the ground running in the direction of the desired station and terminated at the far end in a resistance to ground equal to the characteristic impedance of the line, about 500 ohms."  

In a letter to the December 1981 issue of "QST", Beverage said the antenna "should be no longer than one wavelength at the frequency of interest."  Experts can't agree on what length is best, because the length depends on local ground conditions.  According to Buch, "The bottom line is that one or two wavelengths is probably sufficient for good results."

In my experiments with beverage antennas, I was constrained by the size of my lot to a one wavelength piece of wire.

Is there a simpler approach to a "wave" antenna that doesn't involve very long lengths of wire?  Yes, there is.  It's something amateur radio operators call a "snake" antenna, a design that's been around since the late 1980s.  According to Joseph Buch, the snake consists of 50 ohm coaxial cable, approximately 100 ft/30.48 meters to 200 ft/60.97 meters long, which is laid along the ground or slightly above ground.  The coax cable center conductor is connected to the receiver antenna terminal.  The shield is left floating at the receiver.  The shield and center connector are shorted at the far end.

Last Sunday, 08 June 2014, I built one of these "snake" antennas and was suitably impressed with its receive capabilities, especially on the broadcast band, 160 meters, 80 meters, and 40 meters.  I had 100 ft/30.48 meters of RG-58 coaxial cable in the garage and used that cable to make the antenna.  Once I shorted the shield and center connector at the far end (soldered, of course, and protected from the elements with a tight fitting plastic bag) and connected the center connector to the receiver antenna terminal (leaving the shield to float) of the old Hallicrafters SX-62A, I was ready to go. The snake was rolled out through the garden and pointed towards Hilo (NE).  Stations that were once received with a strength of 54 to 55 were now 59+.  My new house is approximately 15 miles from Hilo, and AM reception is barely tolerable because of line noise and geography issues.

According to W0BTU, beverage and snake antennas are "broadbanded and do not require retuning to QSY because they are non-resonant."  I hooked up the snake to my Ten-Tec Argosy II transceiver and was pleasantly surprised by just how quiet the antenna was.  I did a few experiments using the Argosy II to transmit on my 40 meter vertical, while using an old Kenwood TS-520 to receive with the snake.  This was a great combination.  The snake works quite well on 80 and 40 meters and is often usable on 20 meters.

This combination will not outplay a tribander on a 50 foot/15.24 tower or a dipole supported atop a tall tree, but it does offer acceptable performance in areas of high noise or snoopy neighbors. My snake antenna can't be seen by neighbors, since it runs through the backyard garden into a grove of Norfolk Pine trees.  The vertical is suspended from a tree branch approximately 35 feet/10.67 meters above ground.  Four slightly sloping radial wires are attached to the base of the vertical.  The antenna is fed by 450 ohm ladder line to a 4:1 current balun, which in turn is connected to a Drake MN-4 antenna transmatch.  The antenna can be used from 40 through 10 meters.  If I need 80 meter capability, I switch to my 135 foot/41.15 meter doublet, also fed with 450 ohm ladder line.

If you want a general coverage receive antenna that can be used with a vertical transmitting antenna, you can't beat the "snake".  It's cheap, nearly invisible, and quiet.  This would make an excellent weekend project.

RESOURCES:

f5ad.free.fr/Liens_coupes_ANT/G/K3MT/Antennegazon.htm.

http://www.hard-core-dx.com/nordicdx/antenna/special/swlant.html.(this is a reprint of Joseph Buch's articles in the NASWA Journal, December 1992 and January 1993).

http://www.w0btu.com/Beverage_antenns.html.

http://www.youtube.com/watch?=GAxZs80Wyuw.

http://sa555.blogspot.com.

QST.  January 1982.

QST.  December 1981, letters section.

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.

Sunday, June 8, 2014

Simple Ham Radio Antennas: The "Down To Earth Antenna." Post #279

Are you looking for an inconspicuous amateur radio antenna that is largely invisible, yet delivers acceptable DX and local results?  An antenna idea described by Robert McGregor (VK3XZ) and published in the May, 1993 edition of "Amateur Radio" (Australian magazine) may suggest a few alternatives for hams facing restrictive HOAs and CC&Rs.

A few weeks ago, Dean Manley (KH6B), gave me a copy of this fascinating article for my antenna reference library.  I've built several disguised antennas, ranging from K3MT's "grasswire" antenna to low-lying dipoles running just above my home garden.  But none of this antennas worked as well as "The Down To Earth Antenna" from Robert McGregor (VK3XZ). Here are some pertinent paragraphs from Robert's article.

DOWN TO EARTH ANTENNA

Australia and the African Desert have a common need for radio communication and a mainly sandy terrain. VK5TL's letter, AR Jan. '92 caused me to dig deep into a pile of ancient documents and in "Instructions to Australian Signallers" there was a piece of information for our guidance.  I quote:

1.  A ground aerial is a length of insulated wire attached to the aerial terminal of a wireless set and laid out along the ground in the direction of the distant station.  Although it lies horizontal, it radiates ground waves; it is thus an exception to the general rule that vertical aerials are used for groundwave work.  A ground aerial gives approximately the same range as a 6 ft. rod (vertical whip?  Dean's, KH6B, note).

2.  A ground aerial is useful in positions where a rod would be dangerously conspicuous. It may be buried to a depth of about an inch, to prevent people tripping over it, without losing much of it efficiency.  Ground aerials are less likely to screening than rods, and may provide the only means of getting communication where the sets are in woods or amongst buildings.  A station using a ground aerial can work satisfactory to a station using a rod.

3.  A ground aerial radiates well in the direction of its length, but very badly at right angles to its length.  Ground aerials are unsuitable for large groups on account of their directive properties.

A counterpoise may sometimes be used with a ground aerial.  It consists of another length of insulated wire connected to the earth terminal of the wireless set and laid out along the ground in the opposite direction to the aerial.  When a counterpoise is used, it should point towards the distant station, and the aerial in the opposite, because the radiation will probably be greater in the direction of the counterpoise than in that of the aerial.  The directivity of a ground aerial may be helpful in attaining a degree of secrecy, since little radiation is sent out at right angles to the aerial.

4.  The best length for a ground aerial is:  Distance in feet=(375/Frequency in MHz) or (114.3/f/MHz) in meters.  These lengths are not critical.  If the aerial is short, it will work almost as well; if it is too long, however, the efficiency will be reduced.  Therefore a ground aerial should always be made shorter than the best length rather than longer, which means it should be cut for the highest frequency that may be used.

5.  Insulation--it is important that the aerial and the counterpoise (when used) should be properly insulated.  The most common fault is failure to seal the end of the wire distant from the set.

I point out that in all sets referred to, the output circuit was designed to feed something less than a quarter wavelength.  An outboard series fixed condenser was normally available where the available antenna was too long.  Frequencies were between 4 and 7 MHz.

Tests over this frequency range showed an average difference of 16dB between a 6 ft rod and one of 18 ft. Beyond this height, a small capacity hat, four radial rod, 2 feet long, gave the best results.

Amateur Radio, May, 1993.

McGregor's idea seemed workable, since my new home sits on a full acre of grass and forest land  in the Puna District.  I decided to build  the ground "aerial" with counterpoise as my new experimental antenna.  In some ways, McGregor's antenna resembles the "grasswire" antenna of K3MT, but without the use of a 9:1 balun.  Using the formula 375/f (MHz)=L (ft) and a design frequency of 7.088 MHZ (the frequency of the Hawaii Afternoon Net), I came up with a length of 52.90 feet/16.12 meters for the ground "aerial" and its matching counterpoise.  I rounded off the dimensions to 53 ft/16.15 meters for each wire.

I attached each wire to a Budwig HI-Que Center Coax Connector, with the ground "aerial" being soldered to the + terminal of the connector and the counterpoise wire being soldered to the - terminal of the connector.  I used some #20 AWG hookup wire I had in the shack for the antenna and counterpoise wires.

I then attached a 50 ft/15.24 meters length of RG-8X with UHF connectors to the Budwig Center Connector.  The Center Connector with its attached wires was placed in a small Rubbermaid plastic container to protect the connector from the weather.  The antenna assembly was placed in the garden, with the counterpoise element pointing NW and the ground "aerial" pointing SE.

The coax was led to the patch panel in the shack window, where a short piece of RG-8X from the inside of the patch panel was connected to my Drake MN-4 antenna transmatch (i.e. tuner).  Short lengths of RG-8X connected the Ten Tec Argosy II, the low pass filter, and the Heathkit Dummy Load to the Drake MN-4.  A counterpoise "bundle" consisting of 1/4 wavelength sections of #20 AWG hookup wire for 40, 20, 15, and 10 meters was attached to the ground lug of the Drake MN-4 antenna transmatch.

INITIAL RESULTS

With the Drake MN-4 in line, I was able to get a 1.1:1 SWR across the entire 40 meter band.  Since I made the antenna after the daily net time had passed, I only was able  to test the antenna with stations not working the net.  Signals within the state of Hawaii were excellent, with CW reports ranging from 579 to 599 and SSB reports varying between 57 and 59.  I was running the Argosy II at around 05 watts QRP.  When I reoriented the antenna so that the ground "aerial" pointed to Australia (SW) and the counterpoise was aimed towards the U.S. mainland (NE), I got some good reports on both CW and SSB.  CW ranged from 549 to 579 and SSB varied between 53 to 55.  Nothing to write home about, but the antenna does work, even with low power.  And best of all, my neighbors can't see it.  Out of sight, out of mind.  Give this antenna a try.  It could stop antenna problems before they begin.

REFERENCES:

Personal conversation with Dean Manley (KH6B), 30 May 2014.

McGregor, Robert (VK3XZ).  "Down to Earth Antenna."  "Amateur Radio", May, 1993.


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Monday, June 2, 2014

Simple Ham Radio Antennas: The Aluminum Foil Vertical. Post #278.

I knew it would happen.  The time I ran out of antenna wire.  After several years of using old #14 AWG house wire, #18 AWG speaker wire from Radio Shack, and remnants from studio wiring projects at my former employer (Pacific Radio Group), I had finally exhausted my wire supply for homebrewed antennas.  What to do until the next sale at Lowe's, Home Depot, and Ace Hardware?  Give up? Banish the thought!.

With last week's beautiful weekend before me, I needed some cheap wire to erect my latest antenna "masterpiece."  I found my resource in the kitchen in the form of a new roll of "Diamond Aluminum Foil"--the stuff my xyl uses for cooking tasty treats and dinners.  Since there were several new rolls near the stove, I decided to "borrow" a new roll and apologize later.  Besides, I would buy another roll the next time I visited the supermarket.

According to the label on the container, the roll contained 66.66 yards (199.98 feet) or 60.96 meters of aluminum foil.  The foil measured 12 inches/30.48 cm wide.  By carefully cutting a narrow strip of aluminum foil and taping it to a MFJ telescoping fiberglass mast, I would have the crude beginnings of a 40-10 meter vertical. By attaching carefully cut lengths of aluminum foil to my feed line, I could also make a crude, but satisfactory "counterpoise" system to complement the vertical element.  By using a few aluminum nuts and bolts, I could attach a 450 ohm ladder line to the foil elements and have a multi-band antenna capable of working 40 through 10 meters.  A sturdy antenna transmatch ("tuner") and a 4:1 current balun would permit operation with my Ten-Tec Argosy II transceiver.

If the antenna "fizzled", all I would lose is some aluminum foil and a tarnished ego.  So, with aluminum foil, some basic tools, a spare mast and assorted tape and nylon ties, I ventured forth into the abyss.

MATERIALS:

Here are the materials I had available in the shack and in the garage:

One 33-ft/10.06 meters MFJ telescoping fiberglass mast.

A spare 5-ft/1.52 meters wooden support stake for the mast.

Two, 5-ft/1.52 meters wooden stakes to support the 450 ohm feed line until it reaced the garage wall, where I had positioned a W9INN 4:1 current balun approximately 8-ft/2.43 meters above ground.

Fifty feet/15.24 meters of 450 ohm ladder line.  This would be the antenna feed line.

Six feet/1.82 meters of RG-8X coaxial cable with UHF fittings. This cable would run from the balun to the window patch panel.

Six feet/1.82 meters of RG-8X coaxial cable with UHF fittings. This cable would run from the patch panel to the Drake MN-4 transmatch ("tuner").

Short pieces of RG-8X coaxial cable (3-ft/0.91 meters) to interconnect the Argosy II, low-pass filter, and Heathkit Dummy load to the Drake MN-4.

A "counterpoise bundle" consisting of 1/4 wavelength wire pieces for 40, 20, 15, and 10 meters.  For the counterpoise, I used a wire bundle from a previous antenna project.  The counterpoise bundle would be connected to the ground lug of the Drake MN-4.

And finally, a set of nuts and bolts to attach the aluminium foil vertical element and counterpoise wire to the 450 ohm feed line.

ASSEMBLY:

The antenna was built on the ground.  To determine the length of the vertical element, I used the general formula 234/f (MHz)=L (ft.)  Using 7.088 MHz as my selected frequency (the local "watering hole" for the Hawaii Afternoon Net), I carefully cut an aluminum foil strip 33-ft/10.06 meters long and 0.5-in/1.27 cm wide.  I cut two "counterpoise" wires having the same length and width.

I secured the thin aluminum foil vertical element to the fiberglass mast with nylon ties and vinyl electrical tape.  At the bottom of the vertical element and at the ends of the aluminum foil counterpoise wires nearest the mast, I carefully secured each leg of the 450 ohm ladder line with aluminum nuts and bolts.  One leg went to the vertical element.  One leg went to the junction of the two aluminum foil "counterpoise wires.  I wrapped the base of the fiberglass mast with plastic bags to protect the antenna and counterpoise connections from the weather.

I slowly hoisted the mast onto its wooden support stake and attached the 450 ohm feed line to two wooden support stakes to keep the ladder line off the ground.

The aluminum foil counterpoise lines were carefully supported by low level wooden garden stakes.  The counterpoise elements were approximately 6-in/15.24 cm above ground.

The 450 ohm ladder line was attached to the W9INN balun on the garage wall, a 6-ft/1.82 meters length of RG-8X with UHF connectors was attached to the balun, the coax was led to the window patch panel, and a final 6-ft/1.82 meters length of RG-8X was run from the patch panel to the Drake MN-4.  Smaller pieces of RG-8X connected the transmatch to the Argosy II, the low-pass filter, and the Heathkit Dummy load.  As a final step, I attached a "counterpoise bundle" to the ground lug of the Drake MN-4.

INITIAL RESULTS:

For a rapidly made, spur-of-the-moment antenna, results were surprisingly good.  With the Drake MN-4 in the line, I was able to get a SWR of 1.1 to 1 on 40, 20, 15, and 10 meters.  With the Argosy II running around 10 watts, I was able to get some excellent contacts both in Hawaii (late afternoon) and the U.S. mainland (late morning through early evening hours).  On average, depending on the band in use, CW reports ranged from 559 to 599 and SSB reports fell between 54 to 57.  Not exceptional, to be sure.  But the antenna works.  Best of all, my cost was virtually nil, except for the aluminum foil which my xyl will soon discover is missing.

I'll keep the antenna up for a few weeks, just to see how well it survives our summer showers and tropical heat.

This was a fun and educational project.

REFERENCES:

http://www.arrl.org/hf-vertical.

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

http://astromag.co.uk/vertical.

http://www.wc7l.com/VerticalTheoryp1.htm.

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Aloha es 73 de Russ (KH6JRM).

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

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