AmateurRadio.com

Keen followers of SOTA will have read about this on the SOTA Reflector, but during the last couple of months Richard G3CWI has been activating summits using a 30m transceiver powered by a 9V PP3/MN1604 battery. This apparently is in response to a challenge set by another keen SOTA activator: Kjell, LA1KHA (who visited us in October 2009.)

I couldn’t find many details of the challenge, so I’m just assuming that it was simply to see how many activations could be made using a radio powered by one of these small batteries. Kjell is believed to be using a Small Wonder labs RockMite but Richard built his own transceiver especially for the challenge. The receiver uses a two-crystal ladder filter at the signal frequency, an NE602 mixer, a low noise AF amplifier and active lowpass filter using CMOS op-amps. The transmitter has a crystal oscillator, bipolar buffer, bipolar amplifier and FET class E PA giving 300mW output and an internal Tick1 keyer.

With this transceiver Richard has now activated 10 summits making more than 100 contacts, still using the original PP3 battery! Having established that a PP3-powered transceiver is adequate for reliable activating Richard is now looking for ultra-lightweight HF antennas to get the weight of his portable station down to the absolute minimum.

I think this is a fascinating challenge and hope that Richard will write up the experience in more detail one day, perhaps in his RadCom Portable column or in the G-QRP Club magazine Sprat. This is really what QRP is all about, reducing the equipment to the bare essentials. It also shows the value of CW as the only mode that allows you to use such simple equipment.

Welcome to Handiham World!

You know how people seem to be drawn to making resolutions at this time of year? Losing weight, balancing the checkbook (if you even use one anymore), keeping the house clean, and all the usual things that seem to be hard to get done and awfully easy to leave until tomorrow – those are the usual New Year’s resolutions. Well, on New Year’s Day I was listening to National Public Radio, and I heard a discussion of resolutions, and I thought that they came up with a brilliant suggestion. Since making and keeping resolutions seems to be so difficult, why not quit making resolutions for yourself and instead just make them for other people?

Now, THERE’S an idea! Since I am so lousy at keeping my own resolutions, I will instead tell YOU what you should do. Not only will it be easier for me, you will benefit by my great wisdom and while I sit and drink coffee and eat donuts, YOU can be the one working out at the gym and eating celery. What could possibly go wrong?

So here are my New Year’s resolutions for you:

	You will get on the air every day, if you possibly can. I call this idea DOTA, which stands for “Daily On The Air”. Not only is this a good way to stay in touch with your friends, it is also a necessity if you want to be familiar with your equipment. I was discussing this with Linda, N7HVF, recently in an email exchange. We both agreed that it is hard to remember how to use some of the feature on your equipment if you don’t get on the air regularly, preferably every day.
	You will follow the Amateur’s Code to the best of your ability. The Amateur’s Code appears as regularly as clockwork in each new edition of the ARRL Handbook. It was written by Paul Segal, W9EEA, in 1928, and it is as good a set of guidelines today as it was then. To refresh your memory, the amateur is considerate, loyal, progressive, friendly, balanced, and patriotic. In the months ahead, we will be looking at each of these guidelines individually and discussing each in more depth. I will be happy to have my brand-new 2011 ARRL Handbook available to help us as a reference. It’s an awesome book, and the entire contents – every bit of text – is searchable in PDF on an accompanying compact disk. I’m sure they still have a good price on the Handbook at ARRL.org in case you want to pick one up.
	You will attend your local radio club meetings and do something to participate, whether it is writing an article for the club newsletter, taking a leadership post, being part of an ARES group, volunteering to plan or run an operation on Field Day, helping another club member with a project, or maintaining the club’s equipment, repeater, or website.
	If you are not a member of a radio club, you will find one and (hopefully) join up.
	You will be an ambassador for Amateur Radio by welcoming questions from non-hams about our hobby and by stepping up to the plate to showcase ham radio whenever you can, whether it is at a trade show, school classroom, or through a media outlet.
	You will resolve to give back as much as you get out of ham radio. Get in the habit of saying “yes” when someone asks you to serve, participate, help, whatever. One good way to do this is to be a net control station when someone asks for help covering their net session.
	If you are a member of the Handiham Radio Club, you resolve to participate in the Handiham nets as much as you can, and also help by suggesting club activities and then participating.
	Finally, you will practice good operating skills, and you will start by always using your callsign correctly and never saying “73’s” instead of the correct “73” when you finish a QSO.

I hope these New Year’s resolutions keep you busy. If anyone has resolutions for me, I am holding my hands over my ears right now and saying, “Nyaa, nyaa, nyaa, I can’t heeeear you!”

Shortwave America – alive and growing in 2011

October 21st, 2008 – That’s the day Shortwave America was born. Several inspirations take responsibility for this now popular web publication coming to life, along with necessity being the mother of invention and the sharp mind of a seasoned writer in possession of a dream.

Dan Hensley, KC9NCF, has been an avid lover of radio communications since he was young. His father and mother were both licensed in the radio service long ago, and his father moved on to amateur radio in the 80s. It was in the late 80s that Dan was exposed to commercial radio by Doug Zelden; otherwise known as “Rabbi Doug” who was his grade school teacher and also a semi-regular character on the “Kevin Matthews” show back when WLUP AM – 1000 was still on the air. Doug was responsible for introducing Dan to Kevin and the gang at AM 1000. Ed Tyll then noticed Dan and had him in the studio twice, and then as a regular guest during his late night show via telephone.

In the early 2000’s, John and Jeff of “The John & Jeff Show” got to work with Dan for a short while. It was December of 2006 when Dan got his FCC Technician license, then following up with his General Class License at the last Handiham California Radio Camp in 2008.

Since that October day in 2008, Shortwave America has seen continued growth and has served the mission of keeping radio alive through station loggings, radio related observations, silliness and sarcasm. Mix all of this together with interviews of popular radio personalities, creative flow, ingenuity, hard work, devotion, and what you get is a recipe for success.

This past year, Shortwave America has been featured twice on the longest running short-wave radio show known to mankind; “The Happy Station Show” which was revived by Keith Perron at PCJ Radio. Shortwave America also saw the following highlights in 2010: The creation of a Numbers Station Monitoring Resource that became popular with everyone at Enigma2000 and the Spooks List, a focus on Communications Freedom In Iran that saw Canadian radio host, Shabnam Assadollahi as both an interview subject and a special guest with her interview of Dr, Mehrdad Emadi who is the Senior Economic Adviser to the European Union. As part of that communications freedom focus, Shortwave America also interviewed Mehrdad Emadi and Homayoun Mobasseri of NEDA For A Free Iran.

Pam Mark Hall, a popular Christian Contemporary Music Musician from long ago even promoted that three part series and became a fan of Shortwave America. There was a special focus on RadioReference in the context of their live audio feeds, a piece that went viral involving an 1800 foot tall radio tower climbing video, daily increasing international readership, and a piece that inspired a viral spoof of DXer’s Unlimited host, Arnie Coro.

Shortwave America has become popular with the users of a popular internet HF radio forum called HF Underground and its owner, Chris Smolinski; who also owns the Spy Numbers Database. Shortwave America has seen praise from the likes of Mr. Fahey who was responsible for uncovering and discovering the transponder used by the Chinese Government for operating what is known as “Firedrake” and then isolating the audio channels. That piece was done when it was publicized that the China Radio International Censor tape was publicly released. Other praise has been given by a veteran cryptographer, Pirate Radio Weekly, The Southgate Amateur Radio Club who featured Shortwave America in a piece about residents of Peoria, Illinois becoming upset about a ham who is building several towers in the area, Lisnews, and a list of other sources.

An important piece for Shortwave America that contributed to its growing popularity was “History Of The California Repeater Wars – Part 1” that included audio captured directly by Dan during one of the more disgusting skirmishes on the W6NUT repeater in Los Angeles. During the production of this piece, WA6ITF of Amateur Radio NEWSLINE was interviewed and generously provided some information as part of the focus of that work.

Shortwave America has become so wildly popular that it now has over nine thousand loyal readers and is looking to expand by way of an official website, an on-line product store, and will start giving access to six or more popular radio shows focusing on amateur and short-wave radio. Shortwave America has recently added two listening galleries that readers can use to listen to short-wave stations on-line and will soon feature an amateur radio listening gallery. The first listening gallery is devoted entirely to Radio Netherlands Worldwide. All listening galleries are located at the top of the Shortwave America homepage.

Shortwave America plans more interviews, a podcast, the possible addition of an international liaison team to assist in language translation and relations with readers from across the world. Shortwave America has recently added a reader’s hotline where readers, the general public, and members of the radio community can leave messages about anything that is radio related from breaking news stories to questions, comments, criticism, ideas, discoveries, and any other radio subject matter. You can call the Shortwave America hotline at: 1-206-666-8235.

Eventually, the hotline will become a toll-free 800 number if there is enough interest in it. A reader’s poll was just recently closed, and the stats there will be calculated to determine what the readers want to see, what can become a reality and how best to achieve those goals. Shortwave America is quickly becoming competitive with the most popular mainstream sites such as hfradio.org, RadioReference, hamisland, and will hopefully rival QRZ and E-Ham.

(Information from Shortwave America)

Welcome to Handiham World!

You know how people seem to be drawn to making resolutions at this time of year? Losing weight, balancing the checkbook (if you even use one anymore), keeping the house clean, and all the usual things that seem to be hard to get done and awfully easy to leave until tomorrow – those are the usual New Year’s resolutions. Well, on New Year’s Day I was listening to National Public Radio, and I heard a discussion of resolutions, and I thought that they came up with a brilliant suggestion. Since making and keeping resolutions seems to be so difficult, why not quit making resolutions for yourself and instead just make them for other people?

Now, THERE’S an idea! Since I am so lousy at keeping my own resolutions, I will instead tell YOU what you should do. Not only will it be easier for me, you will benefit by my great wisdom and while I sit and drink coffee and eat donuts, YOU can be the one working out at the gym and eating celery. What could possibly go wrong?

So here are my New Year’s resolutions for you:

	You will get on the air every day, if you possibly can. I call this idea DOTA, which stands for “Daily On The Air”. Not only is this a good way to stay in touch with your friends, it is also a necessity if you want to be familiar with your equipment. I was discussing this with Linda, N7HVF, recently in an email exchange. We both agreed that it is hard to remember how to use some of the feature on your equipment if you don’t get on the air regularly, preferably every day.
	You will follow the Amateur’s Code to the best of your ability. The Amateur’s Code appears as regularly as clockwork in each new edition of the ARRL Handbook. It was written by Paul Segal, W9EEA, in 1928, and it is as good a set of guidelines today as it was then. To refresh your memory, the amateur is considerate, loyal, progressive, friendly, balanced, and patriotic. In the months ahead, we will be looking at each of these guidelines individually and discussing each in more depth. I will be happy to have my brand-new 2011 ARRL Handbook available to help us as a reference. It’s an awesome book, and the entire contents – every bit of text – is searchable in PDF on an accompanying compact disk. I’m sure they still have a good price on the Handbook at ARRL.org in case you want to pick one up.
	You will attend your local radio club meetings and do something to participate, whether it is writing an article for the club newsletter, taking a leadership post, being part of an ARES group, volunteering to plan or run an operation on Field Day, helping another club member with a project, or maintaining the club’s equipment, repeater, or website.
	If you are not a member of a radio club, you will find one and (hopefully) join up.
	You will be an ambassador for Amateur Radio by welcoming questions from non-hams about our hobby and by stepping up to the plate to showcase ham radio whenever you can, whether it is at a trade show, school classroom, or through a media outlet.
	You will resolve to give back as much as you get out of ham radio. Get in the habit of saying “yes” when someone asks you to serve, participate, help, whatever. One good way to do this is to be a net control station when someone asks for help covering their net session.
	If you are a member of the Handiham Radio Club, you resolve to participate in the Handiham nets as much as you can, and also help by suggesting club activities and then participating.
	Finally, you will practice good operating skills, and you will start by always using your callsign correctly and never saying “73’s” instead of the correct “73” when you finish a QSO.

I hope these New Year’s resolutions keep you busy. If anyone has resolutions for me, I am holding my hands over my ears right now and saying, “Nyaa, nyaa, nyaa, I can’t heeeear you!”

Shortwave America – alive and growing in 2011

October 21st, 2008 – That’s the day Shortwave America was born. Several inspirations take responsibility for this now popular web publication coming to life, along with necessity being the mother of invention and the sharp mind of a seasoned writer in possession of a dream.

Dan Hensley, KC9NCF, has been an avid lover of radio communications since he was young. His father and mother were both licensed in the radio service long ago, and his father moved on to amateur radio in the 80s. It was in the late 80s that Dan was exposed to commercial radio by Doug Zelden; otherwise known as “Rabbi Doug” who was his grade school teacher and also a semi-regular character on the “Kevin Matthews” show back when WLUP AM – 1000 was still on the air. Doug was responsible for introducing Dan to Kevin and the gang at AM 1000. Ed Tyll then noticed Dan and had him in the studio twice, and then as a regular guest during his late night show via telephone.

In the early 2000’s, John and Jeff of “The John & Jeff Show” got to work with Dan for a short while. It was December of 2006 when Dan got his FCC Technician license, then following up with his General Class License at the last Handiham California Radio Camp in 2008.

Since that October day in 2008, Shortwave America has seen continued growth and has served the mission of keeping radio alive through station loggings, radio related observations, silliness and sarcasm. Mix all of this together with interviews of popular radio personalities, creative flow, ingenuity, hard work, devotion, and what you get is a recipe for success.

This past year, Shortwave America has been featured twice on the longest running short-wave radio show known to mankind; “The Happy Station Show” which was revived by Keith Perron at PCJ Radio. Shortwave America also saw the following highlights in 2010: The creation of a Numbers Station Monitoring Resource that became popular with everyone at Enigma2000 and the Spooks List, a focus on Communications Freedom In Iran that saw Canadian radio host, Shabnam Assadollahi as both an interview subject and a special guest with her interview of Dr, Mehrdad Emadi who is the Senior Economic Adviser to the European Union. As part of that communications freedom focus, Shortwave America also interviewed Mehrdad Emadi and Homayoun Mobasseri of NEDA For A Free Iran.

Pam Mark Hall, a popular Christian Contemporary Music Musician from long ago even promoted that three part series and became a fan of Shortwave America. There was a special focus on RadioReference in the context of their live audio feeds, a piece that went viral involving an 1800 foot tall radio tower climbing video, daily increasing international readership, and a piece that inspired a viral spoof of DXer’s Unlimited host, Arnie Coro.

Shortwave America has become popular with the users of a popular internet HF radio forum called HF Underground and its owner, Chris Smolinski; who also owns the Spy Numbers Database. Shortwave America has seen praise from the likes of Mr. Fahey who was responsible for uncovering and discovering the transponder used by the Chinese Government for operating what is known as “Firedrake” and then isolating the audio channels. That piece was done when it was publicized that the China Radio International Censor tape was publicly released. Other praise has been given by a veteran cryptographer, Pirate Radio Weekly, The Southgate Amateur Radio Club who featured Shortwave America in a piece about residents of Peoria, Illinois becoming upset about a ham who is building several towers in the area, Lisnews, and a list of other sources.

An important piece for Shortwave America that contributed to its growing popularity was “History Of The California Repeater Wars – Part 1” that included audio captured directly by Dan during one of the more disgusting skirmishes on the W6NUT repeater in Los Angeles. During the production of this piece, WA6ITF of Amateur Radio NEWSLINE was interviewed and generously provided some information as part of the focus of that work.

Shortwave America has become so wildly popular that it now has over nine thousand loyal readers and is looking to expand by way of an official website, an on-line product store, and will start giving access to six or more popular radio shows focusing on amateur and short-wave radio. Shortwave America has recently added two listening galleries that readers can use to listen to short-wave stations on-line and will soon feature an amateur radio listening gallery. The first listening gallery is devoted entirely to Radio Netherlands Worldwide. All listening galleries are located at the top of the Shortwave America homepage.

Shortwave America plans more interviews, a podcast, the possible addition of an international liaison team to assist in language translation and relations with readers from across the world. Shortwave America has recently added a reader’s hotline where readers, the general public, and members of the radio community can leave messages about anything that is radio related from breaking news stories to questions, comments, criticism, ideas, discoveries, and any other radio subject matter. You can call the Shortwave America hotline at: 1-206-666-8235.

Eventually, the hotline will become a toll-free 800 number if there is enough interest in it. A reader’s poll was just recently closed, and the stats there will be calculated to determine what the readers want to see, what can become a reality and how best to achieve those goals. Shortwave America is quickly becoming competitive with the most popular mainstream sites such as hfradio.org, RadioReference, hamisland, and will hopefully rival QRZ and E-Ham.

(Information from Shortwave America)

At the beginning of each year I always think it’s fun to try and set some goals for the year. Sometimes I find my focus changes and I end up not doing them, but it’s always interesting to look back on

Here’s what I’m thinking of at the moment:

1 – Activity. Try to maintain my rule of calling CQ each day on one band or another and to let no CQ call go unsanswered – even if it’s just a quick hello.

2 – 70MHz. I seem to have spent more time on 70MHz than ever before in the last year. I’m currently enjoying 70MHz FM, but I hope to focus on CW/SSB during the Sporadic E season. Although the FT847 gives me some CW/SSB capability at low power and a poor receiver. I want to improve on that. It may involve a transverter driven from the FT817, or perhaps modifying the FT847. Keen to do *SOMETHING* to improve what I can hear on 70MHz.

3 – 50/144/432MHz. I’m keen to install a collinear antenna for these three bands. The intention is to erect a small mast on the house which will also support a TV antenna for the boys’ TV. On top of the mast can go a collinear for 50/144/432 MHz. I’m hoping that I can use this antenna for Sporadic E on 50MHz as well as regular FM operation on 144 and 432MHz. Currently I have no vertically polarised antenna for 144 and 432MHz and it would be useful to be able to scan the FM channels to monitor propagation more closely, as the repeater channels very often show hints of openings before there is adequate activity on SSB.

4 – 1296MHz. I’m getting more intrigued by 1296MHz and would like to get some sort of capability on the band in the year. Not sure whether this may just be simple 1296MHz FM from a handheld or something else. We’ll see. I can do so simple 1297MHz receive using a scanner, so it will be interesting to see if that yields any results.

In physics the Theory of Everything is a scientific quest for the holy grail of theories that will pull everything together in one neat package and explain everything in the universe.  It’s unlikely that we’ll come close to the theory being realized in our lifetimes, but Jeff, KE9V, has perhaps stumbled upon a “Theory of Everything” in amateur radio, if there could be such a thing.  Jeff writes:

“I recently happened upon the home page of a fellow who was newly licensed. This fellow described what he thought ham radio was all about, and in four short sentences he captured the essence of the thing. He wrote that “the ham radio operator is like MacGyver. Bad guys put him in a tough situation, then he uses clever methods to get himself out of those tough spots. Except in ham radio, it is the radio operator who puts himself in these tough spots and then devises clever means to get himself out.”  ”

Jeff goes on to cite various MacGyver scenarios in amateur radio that we’re familiar with, such as operating QRP with little homebrew rigs in parks or on mountaintops.  The MacGyver analogy, while quite simple really sums up for me the raison d’être of amateur radio, and with every sub-hobby from DXing to QRP to homebrewing to contesting to CW, to even, yes, emcomm.

Having struggled with my interest in amateur radio recently, I realized if you lose the MacGyver instinct or curiosity, your interest in amateur radio will wane.  You have to get back in touch with your “inner MacGyver” to rekindle your interest.  That may mean going away from a part of the hobby that has become commonplace and mundane and going to new challenges that give new opportunities to put yourself in a “tough spot.”

I think the MacGyver concept can also explain the public’s perception of amateur radio.  One cannot really appreciate MacGyver’s ingenuity unless A) they benefit from it (i.e. he saves the day) or B) if they themselves are MacGyvers with the knack for doing what he does.  So the public often just doesn’t get what we do.  While other hobbies like playing an instrument such as a guitar (one of my goals for 2011) are as equally arcane or complicated as amateur radio, the general public can understand the benefits and satisfaction of playing an instrument and enjoy the results.  While it’s easier to just go buy some music on iTunes, I don’t see a similar MacGyver scenario with making music.

The MacGyver concept can also explain mode wars within amateur radio.  Anyone who’s been in amateur radio awhile knows that we have CW aficionados among us who think “real radio” must involve CW.  Some take the MacGyver quality too far and don’t see others as being worthy radio amateurs because they put themselves in less of a tough spot than CW ops choose to.  I think there is often a similar sentiment with QRP versus QRO.

One area in amateur radio that can be at odds with this MacGyver concept is emcomm.  I think the MacGyver-like motivation still applies, it’s just that the so-called “tough spot” Jeff refers to is slightly different.  Emcomm participants tend to prepare for a real tough spot by creating simulated tough spots in the form of drills.  The real tough spot rarely, if ever, happens.  To many people inside and outside of amateur radio it’s questionable whether amateur radio is in a position to save the day in these situations, and I think that’s where the trouble with amateur radio emcomm lies today.  I do think however that the MacGyver concept still applies.

I would love to go on a major DXpedition like the South Georgia or Heard Islands, but paradoxically DX chasing holds little interest for me.  Yes,  it’s the MacGyver concept at work again; working DX really doesn’t challenge me but the thought of a DXpedition does.

Perhaps I’ve beaten to death this concept, but Jeff’s article really struck a chord with me.  Keeping in mind what is at the core of our love of amateur radio can undoubtedly guide us, keep us interested and on track for years of enjoyment.

On a side note, I guess I need to give the obligatory “Happy New Year” greeting.  I’ll spare everyone the resolution list as you all probably know what’s on it and I’ll be writing much of the same list again at the end of this year.  :-)  I thank all of you, my readers and fellow radio artisans, for reading my thoughts, rants, and satire here the past year and hope you’ll stick around for another year.  Happy New Year and 73!

The ARRL 10-meter (28-MHz) contest was a couple of weeks ago.  Given that I had bothered to install a 10-meter antenna at this QTH and that conditions seem to be improving, I thought it would be fun to play.

I fired up CQing on Saturday and after a few minutes, Sarah appeared at the shack doorway.  This usually means that something is broken or I’m causing RFI to something she wants to be using.  Since I’m not KT0R, who used to tell his neighbors that he was “busy and please come back on Monday,” I obliged her.  It was the CO detector again.  I unplugged it (it’s battery-backed, so it just means that contesting burns through 9-volt batteries) and returned to the game.  Peace reigned again in the Miller household.

Sneaking in a little bit of contesting before church on Sunday morning is a long-standing habit of mine, although it seems that the Sunday openings are usually better than the Saturday openings.  Today was no exception.  I was working hard to extract a few QSOs out of what appeared to be a mostly dead band and Sarah again showed up at the shack doorway—this time with wet hair and quite agitated.

“The outlet is popping when I plug the hair-dryer into it!”

I assured her that I would take care of it, adding that it was “probably just the radio getting into the GFI.  Let me send a few dits and see if it starts clicking.”

“No, you stay there, I’ll send the dits.  How do you do it?”

“Just press the left paddle.”

And so, Sarah made her first ham radio transmission on 10-meter CW this morning (after which I did identify, for the record).  I confirmed that the outlet made a little click.  She was not completely convinced, but I told her I would shut down while she dried her hair so I could monitor the situation.

The hairdryer (a prior unit), Sarah, and I have had run-ins before.  Several years ago, when we were poor graduate students, a loose screw was causing a nasty vibration in the old hairdryer.  So, I tightened it up and gave it back to her, not knowing that there was another screw floating around inside the case.  One morning, that screw found its way into the motor and sparked.  When Sarah called me on the phone, I thought she’d burnt the house down.  As much as it pains me, I no longer attempt to fix any appliances that cost less than $50 as a result of this episode.

Still worked up, Sarah took the opportunity to grill me about the compatibility of contesting with family life…”When have children, how will you hear them if they’re in trouble and you have your headphones on?  (In jest, I later proposed wiring a baby monitor into the SOnR audio chain.)  Can’t you listen with the speaker?  How will we keep them from eating your little parts, bits of wire, and globs of solder?  Electricity is not a toy!”

We laughed at the last one.  And she added, “I hope they’re all girls who want everything hot pink—so much hot pink that we want to barf.”

I suppose if someone makes a hot-pink Hello Kitty AK-47 (the photo actually looks like a painting of an AR-15) and the Sarah-cuda bow, we can find hot-pink solder irons, paddle finger pieces, headphones, and even radios (I seem to recall that there was a BabyPhat mod’ed hot-pink Motorola HT floating around the web a few years ago).

Anyhow, this post is for Sarah because she puts up with a lot of tinkering, RFI, and headphone time and gets very little blog recognition in return for it.

(The photo above is of Ft Rock, Oregon, taken by me when I was on assignment there.)

Dad and I built a 10-meter rotable dipole some 12-13 years ago using pieces of a large Wilson tribander that I had begged off of a local ham.  It was an interesting mechanical design, using a 3/4-inch CPVC tee fitting as the center insulator and mounting bracket.  The third leg of the tee slipped over a piece of EMT conduit that we had crimped.  The EMT, in turn telescoped into a RadioShack-type TV mast, which was bracketed to our deck.  It was a fun antenna back when 10 meters was fun.

That CPVC tee lasted a good deal longer in the UV and wind than we ever imagined.  Granted, the antenna was stored in my folks’ garage for 7-8 years while I was in college and graduate school.  But, I reinstalled it when we moved to Maryland.  Last week brought high winds to the Mid-Atlantic region and the fitting gave up the ghost:

Fortunately, it takes all of a half-hour and another 33-cent fitting to replace it.  I did think of running a piece of pipe, dowel, or fiberglass across the element for extra strength.  But, I’ll do that if it fails again soon.  The process of repairing the antenna reminded me of the technique we used to tune it, which we thought was very clever at the time.

We used the “magic” 468 to set the initial length of the antenna optimized for 28.400 MHz, which was totally wrong since 468 is intended for bare wire, not tapered aluminum.  Then, we installed it and measured the VSWR across the band (in the shack).  Next, we took the frequency of the minimum VSWR and divided that by the design frequency.  Then, took the antenna down and scaled the length of the antenna by the quotient from the previous step.  Finally, we reinstalled the antenna and measured the VSWR across the band.  It hit dead-on.  Dad was impressed that my first two QSOs were KL7 and ZS!  It was, of course, ten meters when ten meters was good.

This may be old-hat to a lot of folks, but we thought we were geniuses at the time, although it was purely an act of shade-tree engineering!  For those who don’t mind watching sausage made, I will now muse on the validity of the technique.

Suppose you have a “magic factor,” M (=468 or whatever), that defines the frequency of minimum VSWR for an antenna of length l:

Rearranging that will be useful later:

If we take the partial derivative of each side in the first equation, and substitute M from the second equation we get the following relationship:

Cross-multiplying/-dividing and abusing the partial derivative notation to be a small perturbation yields:

This is subtly different from the original technique, which can be derived from this using some small-number approximations.  But, the point is that there exists a simple technique to prune a dipole to resonance.  delta-f is the offset between the design and actual VSWR minimum frequencies, f is the design VSWR minimum, l is the design length, delta-l is the amount that needs to be added (pruned).