The following comes from a text file which I had on my BBS, The Foundation, in the mid-1990s.  It is a tutorial on how to construct a J-pole antenna for 2 meters and 70 cm (AKA the 440 Band) transceivers.  The tutorial was written by Rick Yost, N4VQT, who lives in North Carolina near where I was first licensed.  I do not know Rick, personally.

I have built several of these J-pole antennas.  My first one was mounted on top of my parent’s house when I was first licensed.  Later, it was replaced with a Ringo Ranger II, which I still own (in storage), and became my portable antenna with a water sprinkler base and a little creative connecting.  In time, the antenna was lost, and I made a new one, which I still have today (and temporarily use).  I have also helped others make this simple antenna.

At some point I hope to put my Ringo Ranger on the roof and move the solder connections on my J-pole to the 70cm portion of the antenna for use on 440 MHz.  I never got around to making that connection the last time I made this J-pole.

Thanks to Rick, N4VQT.  These instructions have been invaluable to me over the years.  I appreciate the work you did on this, even 18 years later.

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BUILDING THE 2-METER/70 CM COPPER J-POLE ANTENNA
By Rick Yost N4VQT 19-October-1992

MATERIALS REQUIRED
10 foot section of 1/2″ Copper water pipe
1/2″ copper “T” (2)
1/2″ copper elbow (2)
1/2″ copper end caps (3)
Electrical solder
RG-8U or RG-8X or equivalent coax about 7′ for “pigtails”
PL-259 connector (2)
PL-258 coupler (2)
UG-176 reducer for RG-8X (2) (not required if using RG-8U)
Electrical tape
TOOLS REQUIRED
Butane torch
Pipe cutter or hack saw
File
Pliers
Plumber’s sand paper
Soldering Iron
Ohm Meter
Measuring tape

The overall design of this dual band J-Pole is that the top of the antenna is for the 70CM band and the bottom is for 2M. Both matching stubs face the same direction. Two antenna leads are used (one “Pigtail” for each band).

ASSEMBLY

1) PREPARATION OF COPPER PIPE:
Using the pipe cutter or hack saw, cut the 10′ copper pipe in the following lengths:
3/4 wave radial = 39 1/2 inches (2 - Meters)
3/4 wave radial = 19 inches (70 CM)
1/4 wave radial = 19 1/2 inches (2 - Meters)
1/4 wave radial = 6 5/8 inches (70 CM)
J connector = 1 1/2 inches. (2 - Meters)
J connector = 1 1/2 inches. (70 CM)

The remainder of the copper pipe will be used as a mast mount. Sand the ends of all pipes to ensure a clean surface for soldering.

2) RADIAL ASSEMBLY:
Using the copper “T” connector fittings, connect the 2M 3/4 wave pipe to the mast mount pipe so that both pipes are joined vertically. At the top of the 2M 3/4 wave radial, join the 70CM 3/4 wave using the second “T" connector. Insure that the remaining open holes in the T’s are both facing the same direction. Insert the 2 J connector pipe’s horizontally into the remaining T openings. Using the elbows, connect the 1/4 wave pipe’s to the J connector pipe’s thereby forming the 2 “J” patterns of the antenna (see diagram below). Place the end caps on top of the three radials. Lay the antenna on a flat concrete surface (like a garage floor or sidewalk) so the connections can be heated and soldered without burning the supporting structure. This will also ensure that 1/4 wave matching stubs will be perfectly horizontal with the 3/4 wave radials once the solder cools. Using the torch, heat the copper T fittings and when sufficiently hot, apply the electrical solder to the pipe where it joins the T. Do not apply heat directly to the pipe, just the connector. Repeat this on all connector joints and end caps.

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BUILDING THE 2-METER/70 CM COPPER J-POLE ANTENNA
By Rick Yost N4VQT 19-October-1992

3) PIGTAIL’s ASSEMBLY:
Cut the 7′ length of coax into two lengths, 69 1/2 inches and 14 1/2 inches. The idea here is to have the two ends of the coax hang down and end at about the same point after the coax sections are soldered to the antenna. The lengths are NOT critical as long as both ends are at least 6 inches below the 2M J connector. The aforementioned measurements will position the ends of the coax about 11 inches below the 2M J after the coax sections are soldered to the antenna. The long coax section will be used for 70CM and the short coax section will be used for 2M.

PL-259 CONNECTIONS for 2M and 70CM: If using the RG-8X coax, install the reducer on the coax first. If using RG-8U or similar, the reducer is not required. Also, slide the outer portion of the PL-259 over the coax. Strip the coax end about 1 1/2 inches and peel back the shield of the coax to the insulating jacket. Strip the insulation off the center conductor about 1 inch. Tin the center conductor and wrap the shield around the remaining center conductor insulation. PLEASE be certain not to short the center conductor to the shield. Connect the PL-259 using a twisting motion to the coax ensuring that the center conductor does not short to the shield. Apply solder to the tip of the PL-259 (coax center conductor) and the 4 holes (coax shield) in the body of the PL-259. The PL-258 coupler can then be connected to the PL-259. Using an Ohm meter, ensure that no short exists between the center pin and the outside of the PL-259 connector.

ANTENNA End of Pigtail: Strip the black insulating jacket of the coax about 3 inches exposing the shield of the coax. Peel back the shield of the coax to the insulating jacket and twist the shield to form a tightly woven wire. Using a soldering iron, tin the twisted shield. This must be done for both the 2M and 70CM pigtails.

4) COAX CONNECTIONS:
2-Meters:
Scribe a mark on the 3/4 wave and the 1/4 wave pipes exactly 2 3/4 inches up from the inside portion of the J connector for the 2M section. (see diagram)

70-Centimeters:
Scribe a mark on the 3/4 wave and the 1/4 wave pipes exactly 1 7/8 inches up from the inside portion of the J connector for the 70CM section. (see diagram)

Soldering the connections:
This procedure is described for the 2M portion of the antenna and must be repeated for the 70CM portion. Using the torch, apply heat to the side of the radials where you made the scribes. Apply a small bead of solder on the scribe points and ensure that the solder is adhering to the pipe. After the beads of solder are somewhat cooled, grasp the coax with a pair of pliers and while heating the pipe, (again from the bottom) wait till the solder bead begins to liquify and apply the tinned shield portion of the coax to the 3/4 wave element. (Be sure to connect the shield of the coax to the 3/4 radial as close as you can to the insulating jacket. In other words, after the connection is cooled, you will be cutting off about 2 1/2 inches of unused shield). The tinned shield will also start to liquify and the solder will join the shield to the radial. Remove the heat IMMEDIATELY after you see the solder on the shield liquify with the solder on the radial. Allow the shield connection to cool to room temperature. Using an Ohm meter, check for any shorts between the center conductor and the shield and also check for continuity between the outside portion of the PL-259 and the antenna. Next, the center conductor must be

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BUILDING THE 2-METER/70 CM COPPER J-POLE ANTENNA
By Rick Yost N4VQT 19-October-1992

soldered to the 1/4 wave radial. Again, after the shield side has cooled, bend the center conductor over to the 1/4 wave radial and cut the center conductor insulation to allow the center conductor to be soldered to the antenna. Solder the center conductor using the same method as you did on the shield connection. Allow to cool to room temperature. Cut the excess shield and center conductor from the antenna. Repeat the above for the 70CM portion of the antenna. Using electrical tape, afix the coax to the mast portion of the antenna just below the “J” on the 2M portion. Likewise, using electrical tape, afix the coax for the 70CM portion down the 3/4 wave radial for the 2M portion. (see diagram)

Your 1/2 wave copper dual band J-Pole is now complete just add whatever lengths of coax you need and a 2-meter and 70 centimeter rig and your on the air!

DIAGRAM (not to scale)

Page 3

(Diagram changed from text to graphic to maintain placement of spaces, due to changes in computer text rendering since 1992)


There is discussion on CQ Magazine’s Facebook page concerning the incorporation of other electronic fields into the world of amateur radio.  The conversation can be found here.  Some people feel that amateur radio is a hobby that should almost solely be focused on radio.  Others feel there is plenty of room for other interests, and if nothing else, new enthusiasts might be drawn into the radio hobby through those interests.

I’ve touched on this topic a bit in some of the posts on my regular blog.

Here’s how I see things.

First, ham radios numbers have changed.  Most people will tell you that the number of licensed amateur radio operators had decreased over the years.  I am having trouble finding those statistics.  Sometimes I wonder if people notice the number of active operators has decreased, while the actual number of operators hasn’t changed to match perception.  As operators pass on, licenses forfeited from disuse, and new operators come into the hobby, the number of hams in the US will always change.  Right now, there are 58,800 more hams in 2010 then there were about the same time in 2004.

The biggest change seems to be in age.  It’s hard to find actual age numbers, but the average age of amateur radio operators appear to be in their 40s.  CQ Magazine recently did a survey of their “fans” on Facebook and found the average age was 45.  Granted, this is Facebook we’re talking about, but still, amateur radio operators are not the major demographic of Facebook, and yet of 3500 hams connected to CQ Magazine on Facebook, the average age is about 20-30 years older than the average Facebook user’s age.  As the older generations shrink in population, the hams who joined the hobby within the last 20 years are now between their 30s and 50s.  This makes for a younger mix of people.

Technology has changed.  I can’t give you actual “figures” on how things have changed, but 20 years ago some of the radio technologies we use today were cutting edge.  Digital modes are commonplace now.  Computer integration is still in it’s early stages, but worlds apart from how lightly computers were used in the radio hobby in the 1990s.

With everything changing, and a lot of change with similar technologies outside of amateur radio, you would imagine radio on the cutting edge of discovery more now than ever.

But it’s not.

Amateur radio has it’s cutting edge, for sure.  But compared to the rest of the electronic world, cutting edge in amateur radio often seems like child’s play.

The things that the commercial wireless telecommunications world are wolds apart from amateur radio, even though both utilize some of the same basic practices of radio technology.  Amateur radio doesn’t influence commercial cell phones - cell phones influence and change radio, instead.

For instance, who really needs a radio phone patch these days, given the dominance of the cell phone industry?  I recall using radios that seem archaic to today’s standards, which often feel more like phone components than radio rigs.  A new radio today is much more user-friendly, consumer-friendly, and feature-rich - all due to changes in electronics, which are primarily led by the cell phone industry.

With all this in mind, one might wonder what robotics, computers, and other electronics have to do with amateur radio.  Some will even tell you they have no part in the world of radio.  I feel otherwise.

I believe that radio communications will always be the primary function of the radio hobby.  But excluding other technologies because they are not inherently radio-related is a very short-sighted mistake.

Where would modern digital radio communications be without the computer?  It would barely exist.

Who’s to say there’s no room in radio for robotics, especially when they’re using radio technologies to communicate?  Who’s to say that you can’t use the Internet to make a radio connection, when it does such a wonderful job of supplementing the radio hobby in so many ways?  Why can’t radio be supplemented by various technologies, instead of dwindling in disuse from exclusion from the rest of the technological hobbies?

It seems to me that amateur radio could use some new “methods” of communication.  And they could certainly use the people brought in by inclusion of other hobbies.  I, myself, was brought in by an extensive computing and BBSing hobby.  At some point, amateur radio was a logical addition to what I was already interested in.

Here’s the biggest reason, as I see it, to include other technologies: innovation.

I was inactive in amateur radio for about ten years.  And in those ten years, I’ve seen a lot of change.  But I’ve also seen how the hobby has lagged behind the technological edge.  This week I’ve been playing with APRS - a cutting-edge technology now as it was ten years ago.  However, you would imagine that dozens of new APRS and generic mapping software would have become available.  You would expect to see a pretty modern system being used as the technology has progressed.  In reality, the software used is archaic.  The hardware used is even more ancient.  How many computers still have serial connections on them since the advent of USB ten years ago?  Despite this, most ham radio hardware, if it even has a computer connection, use really old RS-232 serial cable technology rather than the now old standard of USB connectivity.

Perhaps a little infusion of new technology will bring us more capable radios, more integration with computers, and new formats to try our hands at.  I’m shocked that we’re many, many years behind the world of cell phones when all that’s inside the cell phone is a more sophisticated radio device and a miniature computing system.  Like ham radio, a cell phone has telephony, digital services, and station-to-station relay.  And yet, your average amateur radio isn’t much more advanced than they were a decade ago.

So, in my opinion, the more we can bring to the hobby, the better off it will be.  Don’t be so worried about losing sight of radio communications, and be more cognizant of the possibilities with an infusion of new tech.

If you want to regain that cutting edge technology, and if you’d like to see new operators on the air, give other technologies a chance to show how they can fit in with amateur radio.

Remember, we are a hobby of inclusion, nor exclusion.

From Amateur Radio Newsline:

The Florida Repeater Council has officially posted it’s proposed narrow-banding recommendation for 2 meters and 70 centimeters on its website. The concept adopted by the Florida Repeater Council leadership basically follows the narrow-banding in the Part 90 VHF and UHF commercial services. Its also based on the knowledge that most if not all of the newer amateur radio FM equipment available on the market today in the 144 to148 MHz and 430 to 450 MHz range is capable of using 6.25 KHz channels if deviation is set at 2.5 KHz deviation. 

Since the use of these new technology systems usually requires the purchase of new radios which are compatible with the new technology systems, by allocating narrow band channels for only newer technology systems there should be a minimal impact on existing wide band repeaters and their users.

While 12.5 and 6.25 KHz channel spacing has been used on the UHF commercial and amateur bands for some time, the VHF bands have used 15 KHz spacing for decades. Since the legacy spacing of VHF commercial and the 146 to 148 MHz amateur service bands do not permit the use of 12.5 or 6.25 KHz spacing without a complete and disruptive re-farming of the entire band, the Florida Repeater Council is proposing to follow the FCC’s VHF plan for Part 90. This will allow use of 7.5 KHz spacing between the legacy 15 KHz channels in the 146 to 148 MHz subband 2 meter and 10 kHz spacing between the existing 144.5 to 145.5 MHz channels in the lower subband. 

The Florida repeater council says that most newer amateur radio equipment evaluated can program to the 7.5 or 10 KHz spacing without difficulty. However in some case the scanning or stepping functions of some radios may require software or firmware updates to properly scan these new channels in a given radios VFO mode.

The proposed changes will create 71 new frequency pairs for narrow band repeaters on 2 meters. It would also significantly expand the number of UHF narrow band channel pairs available as well. This says the council should provide the needed spectrum for experimentation and development of the newer technology systems that utilize narrow band emission such as D-Star and P-25 digital audio relay services. 

The Florida Repeater Council will be looking for public comment on its proposal by e-mail to narrowbandcomments (at) florida-repeaters (dot) org or at the Melborne Hamfest this coming October. More on this proposed band change is on-line at www.florida-repeaters.org. (KS4VT, FRC)

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I passed the exam!

When I started my interest in amateur radio, there were six different classes of licenses, and I started out at one of the lowest.  Over the years, my license became the lowest of three.  Now I’m in the second class, with only one more left to master.

I’m very happy with myself.  The test was easier than I thought.  I actually scored better on this test than I had in a month of practicing: 91.4%, or 32 correct out of 35 questions.  It was very rewarding.

After accomplishing what I’d set out to do, they asked if I wanted to test for the next level.  It wouldn’t cost any more, so I did.  If I had correctly answered another 19 questions I would have passed (the next level has 50 questions).  But it was nice to leave with what I’d gone in for.

The best part is, I accomplished a task, I completed a goal.  If I can do one thing, I can do others.  And I really needed to prove that to myself.

And a month from now, I hope to be sitting in the same room passing the last exam.

Back to the practice tests…

In less than four hours I will be sitting in the J. Reuben Clark Building on the BYU campus taking a test to advance my amateur radio license.  There’s a chance my beard might make it beyond the invisibility filter my crutches will bring.

This is the test I spoke of about a month ago.

I’ve been studying, on and off, for more than a month.  Honestly, I was able to learn a lot, but there’s still much that I don’t understand.  There isn’t a good online resource for someone wanting to know why the answers are what they are, but loads of sites to tell you how to answer the question.

When I took my first amateur radio exam in October of 1995, there were two parts to the test.  I passed the first one, but failed the second one.  A month later, I passed the second one.  In both cases, I passed off of memorization.  I fear that if I pass this test, it will again be due to memorization.  I pass most of my practice exams online - barely.

All this studying and testing brings me back to a realization I had a couple months ago when I got back into the hobby.

I barely picked up a microphone in about ten years.  With all the advancements we’ve seen in wireless phones, computers, and technology, I expected to be blown away by all the advancements in amateur radio.  But I wasn’t.

While much of ham radio has seen advancement, it wasn’t the degree of advancement I expected.  When I put down my microphone around 2000, my cell phone was bigger than my portable ham radio unit.  Today, my cell phone is large only due to it’s capability as a smartphone, and radios don’t look or function all that differently than they did a decade ago.

Today, I should be able to find a device that doubles as a  miniature computer, works wirelessly with other devices, gives me smartphone-like capabilities with different applications, and allow me to plug in different hardware to accomplish multiple tasks.  A few radios come close to a shadow of this dream, but nothing really hits the mark.  I’m simply disappointed that amateur radio technology is nowhere near what my cell phone is - and they both work on very similar technologies.

So why, with my apparent disappointment, would I bother to take a test giving me the ability (despite the lack of equipment) to do more?

For two major reasons:

First, I set out to do this.  I am determined to start, continue, and complete something.  Especially while I’m stuck at home on disability, drugged up half the time, and in pain.  Especially now.  I have a lifetime of incomplete tasks.  This was one I wanted to complete fifteen years ago.  This is something within my grasp, something which I can show to myself and the world that I actually can accomplish something for myself.  If I can finish this, I can finish other things.

Second, I still enjoy amateur radio.  I wish the hobby were a little different.  The hams in Utah aren’t as conversational as people were in North Carolina.  Perhaps I haven’t met the right people yet.  Or perhaps I had friends in North Carolina that brought me together with the people I liked talking to.  I really wish I had a local radio friend with similar interests to “hang out” with.  But the real point is, I want to take this test to be a part of change for amateur radio.  If I have to be ambitious and start my own club to do it, I will.  If I have to find the most imaginative possibilities for amateur radio, I will seek them out and discover them.  I am determined to make it interesting to me, and to those around me.  Radio can continue to be an old man’s tinkering, or it can become an everyman’s enjoyment.

And that is why,in four hours, I will take the test.  I feel like I’m going against the odds here, but I will make the effort.  If I fail, I will try again.  If I pass, I will move forward.

There is one more level above the one I’m testing for tonight.  There’s the effort to modernize the notion of amateur radio.  There’s the indiscriminating nature of the hobby to bring in all walks of people, regardless of color, race, background, education, ability, and religion - something radio operators in Utah seem to have neglected.  And on top of that, I have my most powerful skill at my disposal: my voice, both audibly and written  - a voice that will make an effort to call for change where needed.

I may not understand all of the technology, but I understand that it takes all types to move the hobby forward.  My role will be that of the voice.

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