Category Archives: Interviews

BBC World Service interviews Paul (N6PSE)who is attempting to organize a DXpedition to North Korea

(Source: BBC World Service)

A small group of US ham radio enthusiasts have been in North Korea recently to ask for permission to set up a ‘pop up’ ham radio station there. Paul Ewing is one of them; he wants to lead a group to set up a call sign for two weeks, to make contacts around the world from perhaps the most isolated society in the world. The BBC’s Dan Damon asked Paul to explain.

Harold’s JA7HJ tower was not your average tower

Harold's JA7HJ tower (Click to enlarge)
Harold’s 30′ JA7HJ tower (Click to enlarge)

I meet some very interesting people in radio circles.  My friend Harold Johnson (W4ZCB) is undoubtedly one of them.

Last year at my local ham radio/DXer club meeting, members were asked to bring photos of shacks and rigs, and describe our evolution as ham radio operators. In the series of photos that arrived at the following meeting, one in particular stood out: Harold Johnson’s radio tower in post-war Japan.

Johnson’s tower stood almost thirty feet tall and supported a 20 meter Yagi which you can see in the above photo.  Johnson, who at the time operated under the callsign JA7HJ, also had a little ham shack built. The shack materials–including the tower, Johnson recalls–cost him “three bottles of Scotch for the army quartermaster…I paid the Japanese builder $15 or $20 for the complete  enchilada.” This tower was built entirely of wood: the vertical members were 2′ x 4’s, the slats were 1′ x 3’s.

Of course, the tower didn’t have a mechanical rotor; instead, Johnson climbed inside the tower, lifted the wooden boom, rotated it manually, and placed it back on the uprights.

When asked how he powered his station, Johnson pointed to the wheeled generator in front of the radio shack in the photo. “The generator was called a B6B–it produced 24, 120, 240, and 480 volts, and was rated 10 kW.” When I asked how he managed to procure the generator, he replied that he “borrowed it from the flight line, which was about 300 feet away.”

Johnson's Nashville, TN shack, circa 1955/56. (Click to enlarge)
Johnson’s Nashville, TN shack, circa 1955/56. (Click to enlarge)

I always enjoy hearing personal histories in radio and I didn’t doubt for a moment that Harold Johnson’s would be intriguing, so I asked if he’d tell us how his interest in radio began. So, here’s Johnson’s story in his own words:

As a preteen, (and poor as a church mouse during our previous
Depression), I would visit my aunt and uncle in the summer, likely due to the fact that they were farmers and had food to eat. They owned an old Philco radio that had shortwave bands and I was intrigued with the phone amateurs on the 80 and 20 meter bands. Often, I could hear both sides of the conversation, after I found out that they were on various different frequencies, being crystal controlled back then! My…How times have changed.

In high school, I found another afficianado, and can recall melting “Woods metal” in boiling water and floating a piece of Galena on it until it returned to a solid and [thus] made my own crystal set. WWII had started by then, and I would listen to the ground-to-air communications between ships in Lake Michigan and pilots taking off and landing on them. Great DX, perhaps 10 miles away.

In 1943, I had graduated from high school and joined the US Army Air Corps. Went through training and was still in training (…to be a pilot until they counted airplanes and pilots and decided they had enough of each […so instead] turned me into a B-29 gunner). The war was over whilst [I was] still in training and I “retired” in November 1945. Went home and found my high school sweetheart, married, went back to school to finish my education and started the Johnson family. Still married, and
to the same girl. What a sweetheart to have put up with me all these years. [No kidding, Harold!]

Went back in the US Air Force in 1949, this time became a pilot, and just in time to go to Korea for a year. However, during training, had to learn the Morse and if you learned to 13 WPM, you had a free hour and didn’t have to attend class. That overcame my obstacle to amateur radio, and I took the exams in 1950 and became W9PJO. Our rules at that time were that you had to hold a “class B” ticket for a year before you could take the “class A” exams. That year I spent in Korea and Japan and managed to obtain my first foreign call, JA7HJ.

W4ZCBqslReturning home to wife and by that time two children, I took the class A exams and became W4ZCB. I decided that I enjoyed flying, (at least most of the time), and decided to make it a career. The ensuing years, I was always on and in the air, and usually spent the winters in Alaska and the summers in the Canal Zone, anything to practice how to be miserable. Lebanon in 1958, Vietnam in 1968 and by 1969 decided that I should start doing something else before my luck ran out.

During my last 4 years of service I flew an Army four star around the world four times. Fortunately he was Ted Conway, W4EII, and we mutually enjoyed operating under a couple dozen different call signs from a lot of exotic (and several not so exotic) places. Had G5AHB back when the 5 was reserved for foreign nationals. We were good friends after we both retired (on the same day; I always liked to say that he couldn’t stand to serve without me) until his death in 1990.

I started a small company manufacturing electronic test equipment for public utilities; spent the next 20 years doing that (and enjoying a much more stable life with family and radio.) Managed to work all the countries (entities these days) there are, win a few contests from a contest station I built and operated for 10 years. (80, 40, and 20 in the front room, 15 in one bedroom and since 160 and 10 were seldom open at the same time, they shared the other bedroom. To change bands, you just changed chairs. Five big towers and Yagis, a VERY  high maintenance hobby in the lightning prone state of Florida. (Let’s not mention hurricanes!)

Retired again to the beautiful mountains of North Carolina in 1986. A much more modest station these days, but active on all the HF bands. I really enjoy building homebrew radios and maintaining daily schedules with friends worldwide. Can be found daily on 21.203 with G3XJP and often joined by other builders of the magnificent PicaStar transceiver designed by him. Sixty-three years a ham, still enjoying it. It’s guided my careers and interests. What a wonderful hobby!

W4ZCB's shack today is based around his home brew SDR transceiver, the PicaStar. (Click to enlarge)
W4ZCB’s shack today is based around his home brew SDR transceiver, the PicaStar. (Click to enlarge)

Over the past few years, I’ve gotten to know Harold Johnson; I must say, he has to be one of the very few hams I know who knows the inner workings of tube/valve radios as well as he does the highest tech radios on the market, a rare talent indeed. If you’re trying to learn a bit more about the BC-348 series of radios and trying to diagnose a problem with it, Johnson’s your guy. If you’re trying to build an SDR from scratch, he’s also your guy.  And clearly, if you want to hear a fascinating account of a life influenced by radio, this is most definitely your guy.

Thanks, Harold, for letting me share your story!

Check out Harold Johnson’s website by clicking here.

Author interview: Dennis Blanchard’s (K1YPP) “Three Hundred Zeroes: Lessons of the Heart on the Appalachian Trail”

Dennis Blanchard (K1YPP) at Four Days In May 2012

This year, at the Four Days in May (FDiM) Dayton QRP gathering, I had the pleasure of meeting Dennis Blanchard (K1YPP) and his wife, Jane, as Blanchard signed copies of his book, Three Hundred Zeroes: Lessons of the Heart on the Appalachian Trail. I had previously heard about Blanchard’s book, and it was great meeting the author in person.  Both he and his wife were most friendly, and I instantly felt a connection–after all, he is a fellow QRPer!

As a result of this meeting, I recently decided to purchased a copy of Three Hundred Zeroes on my Kindle eBook reader. Though I’ve always been a fan of turning pages on a traditional book, the eReader does afford one instant gratification, as you can order it on-the-go and start reading immediately.  And that’s exactly what I did…

The result? I’m very glad I took the time to read Blanchard’s Three Hundred Zeros.  Though I don’t like to spend much time away from my young family at present, I’ve always thought it would be a wonderful challenge and adventure to through-hike the AT (Appalachian Trail); reading this book was a vicarious opportunity to do so. Indeed, my favorite trail, the BT–the Bartram Trail, which follows the path of early American naturalist and explorer William Bartram–which I hike when I can, and whose NC chapter I’ve served as a board member for nearly 10 years now, parallels the AT at different points.  So the temptation to hike (and QRP, of course) continues.

“This photo was taken in NJ. Shortly after I took these photos, and walked down the trail about a 100 feet, a bear came over to check the table to see if I had left anything.” (Photo: K1YPP)

Blanchard’s book gives me hope. Three Hundred Zeroes is a well-documented, informative, and–despite his truly serious heart condition–often humorous journal-style account of his successful thru-hike of this 2176 mile trail. His writing style is very informal and likeable, focusing on the many personal interactions that make the trail hiker’s experience unique, and interweaving his day-to-day accounts with trail lore and history.

In contrast with the arduous journey Bill Bryson describes his well-known (and hilarious) book, A Walk in the Woods, in Three Hundred Zeros Blanchard calmly and routinely deals with misadventures and hair-raising encounters with wildlife, rolling with the punches and somehow emerging unscathed. He describes the journey as “long stretches of boredom, punctuated by brief moments of excitement” in the lively and unpredictable form of bears, mice, snakes, and even other hikers, to some degree. Blanchard was obviously a great hiking companion, thus rarely hiked alone–no doubt, other hikers sought his company.

A closeup of Dennis’ AT Sprint 3A taked at Four Days in May (Click to enlarge)

With QRP in mind, I had a few questions for Blanchard after reading his book.  He has kindly taken the time to respond to QRPer‘s questions, as follows.

QRPer:  I always thought that the AT would be a lonely place, but your book certainly changed my mind. Were there many stretches of trail where you were completely alone while trekking or camping at night?

Blanchard: There were times when I was alone for extended periods. However, “alone” is a relative term. Throughout the day I would encounter other hikers going in the other direction, or people that were slower or faster than I. In 180 days on the trail, I think I had three nights when I camped alone.

“2007-Damascus, VA was where I operated Field Day in 2007. It was shortly after this that I left the trail for the heart surgery.” (Photo: K1YPP)

QRPer: What was your favorite stretch of trail?

Blanchard: That’s difficult to answer…The trail is so varied and weather can change one’s views of any section. For me, it was a coin toss between the New Hampshire White Mountains and the 100 Mile Wilderness in Maine. The remoteness of both areas was just so spectacular. Of course the high altitudes made for great antenna opportunities as well.

QRPer: Did you bring a radio to listen to local AM/FM or shortwave?

Blanchard: For most of the hike, I carried a Yaesu VX-1R 2/440 handi-talkie. I think I used it about three times on two-meters. In a few situations, such as up in the White Mountains, I used the VX-1R to tune in NOAA for weather news. It also has AM/FM and on a few very rare occasions, I tuned into local stations for news. Would I carry it again? I don’t know. It is wise to have something for emergencies, and the radio wasn’t too big or heavy, but it was extra weight.

QRPer:  Specifically, what ham gear did you take with you? Do you have a photo?

Blanchard:As noted in the book, I did carry a home-brewed 80/40 meter CW rig for the first 600 miles. For the rest of the hike I carried Steve Weber’s ATS-3A. The radio was powered by six Energizer disposable lithiums, in a home-brewed battery pack. The pack could also charge my cell phone and power the 2-meter VX-1R radio. I used a 51 foot random wire for the antenna and some counterpoise wire, usually about 15 feet. Altogether, the gear weighed around two pounds.

QRPer: If you were to do the hike again, would you take the same equipment?

Blanchard: I’m not certain I would carry the VX-1R again. I didn’t use it much and it is extra weight. However, the NOAA weather, and 2-meter capability could prove extremely useful in an emergency.

QRPer:What was it like coming back off the trail once you completed it? Any especially notable things about how you perceived the world around you? Did it change you? Any culture shock?

Blanchard: The only real “culture shock” was riding in automobiles. Everything seemed to move so quickly. I much more enjoy walking and biking now. I would be happy if I never had to drive again.

“KD2VX, Kathy, was the trail angel that helped out with my hike up in New Hampshire. She is a QRP fan.” (Photo: K1YPP)

QRPer: How many other hams did you meet on the AT who were either through-hiking the AT, or hiking sections?

Blanchard: Since we [hikers] don’t wear being a “ham” on our sleeve[s], I can’t really say how many hams I encountered. The few that I was aware of were mostly section hiking. One benefit of setting up my QRP station along the way was public visibility for ham radio. On a number of occasions I inspired my fellow hikers to look into ham radio when they returned home. I’ve even had a few readers of the book write me to tell me they went off and got a ham license based on inspiration from the book.

QRPer: If any other QRPers are inspired by your story, and are thinking about hiking the entire AT, how much money should they budget for such an adventure? Based on what I read, there are a number of budgetary considerations for shuttles, food, gear, and the like.

“Duncannon, PA was were I operated Field Day. The station table was a few rocks I moved around.” (Photo: K1YPP)

Blanchard: The answer to this question depends on how many “creature comforts” one wishes. Hiking as I did, with stops along the way about every 5-10 days, can cost about $1-$3 a mile. Those on a tight budget could do it for much less, and those that enjoy getting to hotels and eating in fancier places could spend more. Most of the shuttles were really not that expensive, at least those that cater specifically to hikers. The hostels are a real bargain, compared to standard hotels, but one may have to tolerate annoyances, such as snoring and people coming and going at unusual hours. If you’re a light sleeper, this could be an issue.

QRPer: On zero days [based on your descriptions] it seems like hikers simply stuff themselves with food. I’m really curious what you typically ate on the trail?

K1YPP’s 2008 Field Day “table” in Duncannon, PA (Click to enlarge, Photo: K1YPP)

Blanchard:The short answer is: I ate everything. I’m not fussy, and don’t have any diet limitations. If someone is diabetic, or vegetarian, it is still possible to undertake such a hike, it just might require more preparation. My typical day was a few Pop Tarts first thing in the morning, or hot oatmeal on cold days, followed by an on-trail mid-morning snack, such as a Snickers Bars or trail mix.

Lunch was usually something that didn’t need cooking. Roll-up tortillas, or bagels with peanut butter won out most of the time. In the colder weather, bagels and cream cheese was a favorite. Gatorade powder mix, or hot chocolate in cold weather, was my favorite drink for lunch.

The evening meal was usually a pasta-based affair, or couscous. I really preferred the couscous; it is very light to carry, needs very little energy to cook, and is loaded with nutrients. I would usually stir in some dried vegetables with it, or dried meat. As a side I would carry a dried sausage, such as pepperoni, which could also serve as a snack for lunch. I usually carried some desert items as well, such as cookies or dried fruit. Of course energy bars would supplement all of this along the way. Many hikers preferred candy bars, but I tried to avoid them in the warmer weather since they melt.

Overall, even though the diet sounds bland, it wasn’t bad. Of course, whenever we hit a town, I would stuff on everything in sight. I actually did eat well, but couldn’t find enough calories to maintain my weight. I ended up losing 35 pounds at the end of the hike and looked like a refugee.

Well, Dennis–all I can say is that I hope you’ve gained back some of those lost pounds, continue to be in good heart-health, and are able to enjoy a little QRP on your forthcoming hikes.  Thanks very much for taking the time to answer our questions; we wish you the very best!

You can purchase Dennis’ book from or Barnes and Noble and visit his website at

Vlado’s challenge: home-brewed QRP DXCC

Vlado (N3CZ)

My good friend, Vladimir (Vlado) Karamitrov (N3CZ/ZS6MG) is someone who likes to challenge himself. Perhaps this is why he’s such an accomplished DXer and contester.

Recently, at his QTH, he showed me one of his latest projects: a home brewed QRP transceiver. Vlado wasn’t content to simply build his own high-performance transceiver; no, he needed a built-in challenge.

Here is the story of his QRP radio, that he built mostly from junk parts, in his own words:

N3CZ's QRP rig front face

Challenge for all of us ….”Built your own radio”

By N3CZ / ZS6MG, Vladimir Karamitrov, 114 Russet Ln. Asheville, NC 28803 USA

Building your own radio is a challenge on its own. Using it to work DXCC is another challenge, probably less difficult. But combining the two brings a new spark and joy in our hobby. Isn’t ham radio about radios?

The purpose of this article is not to argue the need for building but to give ideas to those who have the time, like a new challenge and open up for ideas of building their own radios.

There are many different aspects to look into this. One is to build a radio from a kit. A search online will provide a list of manufacturers who offer these kits from basic thru intermediate to advanced designs.

The other approach is to build it your self. Yes, from scratch. Well, why not? Remember, time is what is needed most and of course some money and/or spare parts or junk parts. Time is not what I have available a lot, money is always on the agenda but having spare parts and stuff lying around your garage is another good resource.

N3CZ's workbench

So I decided to put something together. No time –means I can’t spend a lot on making this new rig look like a factory made, I have to use dead-bug design techniques and other easy methods to “glue” everything together. Available time is only after work and weekends and that is not much.

What kind a circuit and design to use? This was really the main question, because the answer will dictate what approach to take. First rule is check what parts and components you have available. There is something you have to remember here — when you go to a hamfest always bring some “junk” back home. You never know what you going to need. We all know this rule don’t we? Also don’t forget what your buddies have collected over the years, they will be able to help you with some of the missing parts if you need.

One of my passions is building my own equipment. Starting from antennas, to control boxes to switch them, pre-amps for the low bands and from time to time build a small QRP rig. Other interests are DX and Contesting, so while putting this radio together I cannot wait to hook it up to my antenna. This is where a little patience is required and I had almost none, hi. But I knew, bands are down for now, I have worked almost everything that was there to work, so will do this one little different and try to slow down a bit.

With my projects everything starts with the box. Few boxes I changed until the right one was in my hand. Next was to find a properly sized knob for the VFO. I then realized that it will take little more time to build all the components so I decided to use my $$ budget and get my self a nice DDS VFO. There are few different ones available online and for around $80. I got a nice programmable one with dual VFO’s and memories, with settable IF offset etc. This seemed to be the perfect fit for the project.


I thought I had all I need to start working on this project, but…..I wasn’t really sure about it yet. While looking for the “start” button and to actually take off with this project, I had yet to find that “trigger” that ignites the spark inside me, so I can say to myself, “yes I am ready, let’s just do this.”

You know the feeling – you feel a bit lazy at the beginning until that moment when that spark gets you. It’s like when you have to mow the lawn, and then you think, “no, it can wait another week, don’t feel like doing it now.” Well, I found my spark – it was not in the box, it was in the tuning knob that I got from a colleague also a ham and one who builds little QRP’s. I was actually explaining to him what I was planning to do, but not sure yet of the concept and how to handle certain parts of the circuit. While discussing all of this, he said he had some parts that he would bring for me and see if I could use some. He did not mention about any knobs, but when I saw them I knew I had what I was missing and now it iss the time to start working on this.

Transmitter PA

Now that I have the heart and the body, and the knob, I did some study of a number of different circuits published in ham radio literature including ARRL’s handbook and many online QRP resources. The goal was to build a simple radio easily reproducible, with reasonably good specifications so you can use it daily. Selection of IF frequency was the next and I decided on using 4MHz as I had access to a pile of some computer xtals of 4.032MHz.

Transmitter keying circuit and low pass filter

Junk stock provided the following:

  • Double balanced mixer SBL-1,
  • some 2N5109’s, J310 FET’s,
  • a few IF amps MC1350,
  • some toroids and
  • wire

I was ready to take on my own challenge – build it and work 100 countries with it!

Associated pictures with this article represent certain stages of the building process. As you can see I picked up an easy method for putting all together. I liked this approach for a simple reason that I can go step by step, keep adding components and test each stage as I move forward. There was no need for making PCB…who needs a PCB. In the old days, radios were built on a chassis and components hanging in the air and radio worked.

RX/TX antenna relay

On the other hand there was that perfection starring at me and making me feel a bit guilty, but I had no time to waste but hurry and build this radio in the short time I had available to me. Because you know what, the bands will just open up again, and then I had to do my other part – the DXing, hi so I may not be able to get this done.

I actually put the receiver in a working shape in one afternoon. I had the front end bandpass filter , double balanced mixed, post mixer amp, xtal filter, IF stage and audio section. All tested and worked first time. I spend the rest of the evening listening on 20m. Nothing much there but I found few stations up the band. There were few UA0’s as well. I managed to pick them up but signals were tiny. I decided to check my main radio and compare. I see now…signals were stronger, much stronger, S9 + on my TS850. So I checked few things and found few problems with my initial design: I had to amplify the input signal and my LO signal was too low to produce satisfactory mixing with SBL1. I used a J310 FET transistor for my front end pre-amp, and used single NPN transistor to boost the output of the DDS oscillator to appropriate level.

The receiver

I was ready to fire this thing and …wow, what a difference. I could still hear the UA0’s calling CQ and working others, and the signals were just incredible. Next obstacle was the Xtal filter. I had choose computer xtals that were somewhat matched in frequency, but the filter was way too narrow. I started experimenting with the capacitors around it and found a good medium that showed some good response on the signal quality and bandwidth.

Received signals now sounded “almost” like my ‘850. But I wasn’t happy yet. I was missing some “dynamics” in the signal. It was just a plain CW signal and nothing more to it. Next few days I experimented with an AGC circuit and variable bandwidth for the Xtal filter. After number of changes, I came up with a solid audio AGC circuit and S-Meter. That made a whole lot of difference. Everything was still sitting on the bench, loosely connected together and I was listening up and down the band. There were more stations now…hmm the bands must be opening up or something?

Receiver (left) & Transmitter (right)

For the xtals filter I ended up replacing the fixed caps with varicap diodes which I pulled out from an old TV tuner found at one of the local hamfests. You know that feeling when you can actually adjust xtal filter bandwidth. That is what was missing. I spend hours listening and trying to get into motion for my next step. I was simply amazed what I could pick up with the receiver and how I was able to select different signals, some of them very weak.

I went back and forth between my main radio and this little receiver that was sitting in front of me, still in pieces. “Not much difference is it?”–I was thinking to myself. I actually ended up spending hours in this year’s CQ WPX CW contest and only listening on my new receiver. I was able to pick every signal I wanted, even thru some heavy pile ups. It passed the test! Now I wanted to call these all these stations, so it was time for me to start thinking about the transmitter part.

Receiver front end and mixer

This was nother challenge. I tried one circuit and it worked. Straight forward a TX mixer, bandpass filter, couple stages amplification, low pass filter to the antenna. But I could not get the output power I wanted. I was getting something like 1 W barely making it to 2W. I figured out the reason. It was the transistors I used. Each stage must have enough gain to drive the next one. My final transistor was capable of producing an easy 10 watts out, but I was lacking drive power. I checked the complete circuit and components I had available on hand then decided to make few changes. Remember: the goal was to use what was available and not to go and spend any extra money. I ended up adding extra amplification after the TX mixer. Yep! That was it. That is what I was missing. I was now getting an easy 8W out. I couldn’t wait to hook up the antenna. I had no antenna switching circuit yet, so I hooked up my 3 element SteppIR on the little transmitter and used my vertical antenna on the main radio. Nothing easier than this. I was able to hear my transmitted signal and, at the same time, I could listen on frequency. First call and into UR land…559, “not bad,” I though. I then moved up the band and found a French station ending up a QSO, so I called him and worked him too. I got 579 for my signal. This was getting exciting. I ended up working 10 different countries that evening, mostly Europeans.

I spent the next week or so working on the box and figuring out how to implement the mechanical part of this project and get everything together. I tried using the little radio on 2 different bands (20 and 17M) with excellent results. These have been my main bands this year after they stabilized somewhat and we have them open after work until late. This is the perfect time for experimenting.

Receiver bandpass filter

Final touches can be seen on the rest of the pictures displayed here. I actually used this rig in the IARU CW contest for a while as well as in few QSO party’s on 20m, all with great success. The crown of everything was still to come.

It was getting close to the end of ST0R operation and I had them worked with my main station and KW into antenna on every possible band and mode I could hear them, but that one evening I was listening to their easy going pile-up on 20m working NA stations. The pile-up wasn’t that big and I was thinking,
“should I try this little rig and see if maybe somehow they will hear me?” I wasn’t sure this was going to work, but I hooked up my memory keyer and started pushing the button to send my callsign out. I did this for almost 2 hours. Yes, there was nothing else to do, while I was reading a magazine, I just used the preprogrammed call sign and kept sending it over and over.

Top view of N3CZ's QRP transceiver

Then I heard Lynn W4NL working ST0R with his QRP rig…NO WAY! What is he doing differently then me? And I am going crazy and about to give up, but….I was careful enough to check what frequency was W4NL transmitting so I tune up a little higher then he was. At the same time I received email from Lynn saying he worked ST0R QRP! Yes, I know I heard you Lynn…so I pressed few more time on the keyer. Guess what? It took couple more calls and there he was….smiling at me ST0R called me N3CZ 599 BK. There must have been another CZ I thought, so I send my call, then 599 and then my call again. Sure enough he came back with N3CZ TU. That was it! I did it! I just worked ST0R–a new country in a pile-up with my little homemade radio. I had them worked already on 20 CW , so what if it was a dupe? I knew I did it with my little radio and that was good enough for me. This is where I actually stopped and realized that I have accomplished my challenge. At least I have made it to a milestone, a major milestone. At that time I had well over 60 DXCC countries worked with the little radio, and it was barely 2 and a half months since I started working on this project.

I found this encouraging and I would challenge those readers who are thinking about a similar endeavor to not think twice–just do it!  Order yourself a kit at least and put it together. The reward cannot be described here or told by anyone. You have to feel it on your own. Put a challenge for yourself. Make a goal to work 10 states maybe or 10 DXCC countries, or 100. It doesn’t really matter. What matters most is that you give this hobby of ours another chance. A chance that makes it different from any other hobby on this beautiful planet we live on. What better can it be than communicating with others over a the vast emptiness of the space around us and bounce few signals now and then of the ionosphere?

“DX RULES” as my good friend Bill N2WB from Florida say.

N3CZ's QRP rig front face

I say “HAM RADIO RULES!” nourish it with everyday ideas, build your own stuff, don’t just buy that new radio and antenna, ready assembled and waiting for you to simply push few buttons and “work that rare DX”. There are many aspects of this hobby and like with anything in life we have to find it on our own. Sometimes we get help from another ham, sometimes a complete stranger to us, but with the same ideas.

Thanks to Dave K4SV, Phil W9IXX, Lynn W4NL and Carl N4AA who insisted on getting this article done [originally for The DX Magazine]. And all the stations who logged N3CZ/QRP. That was me who called you with this little homebuilt-junk parts radio. Drop me a note if you find this interesting and inspiring, because that was my intention anyway. By the way, I am already gathering parts for my next project. This time it really started with a nice box, but we’ll see. I don’t see that spark yet. I will let you know how it goes.

Until then,
73 & CU on the bands.
TU de N3CZ / ZS6MG / Z35C

And thank you, Vlado, for sharing this article for readers! To contact Vlado, grab his email from

If you have a home-brew QRP project that you would like to share with readers, simply contact us or comment!

Ten-Tec Answers Your Questions About the Model 539 QRP Transceiver and Model 418 100 Watt Amplifier

The much-anticipated Ten-Tec Model 539 QRP transceiver and Model 418 100 watt amplifier are described in the following interview with Ten-Tec conducted by Tom Witherspoon, K4SWL, of For those who are interested, the “Ten-Tec” in the following interview transcription is actually a collective of three gentlemen, namely,  Ten-Tec representatives Jack Burchfield (President of Ten-Tec), John Henry (Ten-Tec Software Engineer), and Stan Brock (Ten-Tec Sales/Marketing). 

Model 539 QRP transceiver

Frequency Coverage/Bands

Prototype of the Ten-Tec Model 539 QRP transceiver

QRPer: Will the 539 offer 160 meters? Some readers noticed that the Model 418 amplifier lists 160M as a feature, but the Model 539 doesn’t.
Ten-Tec: 160 Meters is a possibility on the Model 539, and Ten-Tec is looking into it.

QRPer: Could the 539 offer 6 meters at some point?
Ten-Tec: We doubt this will be included.

QRPer: How about 60M?
Ten-Tec: Probably not.

QRPer: One reader asked if ithe Model 539 would have the 0.5 to 1.6 MHz AM broadcast band. Is this a possibility?
Ten-Tec: Yes, though still to be determined, it may be possible to receive well into the AM broadcast band. The Model 539, of course, will be optimized for the ham radio bands, thus audio fidelity from an AM broadcaster will be somewhat compromised.


QRPer: We know it’s early days, but what’s the target price for both the Model 539 and 418?
Ten-Tec: These are early days, indeed, but we believe the Model 539 transceiver will probably sell for less than $1000 US. As for the Model 418 Amplifier, pricing is yet to be determined.


QRPer: Will the Model 539 have accessibility built in for the blind operator?
Ten-Tec: The Model 539 will be a computer controlled transceiver. Many of our visually impaired operators, use, for example, applications like Jaws to adapt our Ten-Tec gear for accessibility.

QRPer: Will the Model 539 have a built-in antenna tuner? Or as an option?
Ten-Tec: Due to size constraints, we currently have no plans for this option. Following the legacy of the early Argonaut transceivers, where simplicity and performance were key, we would not want to compromise the radio’s size to add a mediocre ATU.

QRPer: Will AGC also feature an “Off” position?
Ten-Tec: The Model 539 is a DSP-based transceiver, as such, there is no real “Off” position. This is really true on all HF DSP transceivers. The AGC function is a part of the DSP algorithm. With that said, if you turn down the RF gain far enough, it will act like a normal analog radio: it will not start AGCing until maybe S7 or S8. The Model 539 will have a selectable AGC with slow through fast speeds.

QRPer: So, will the Model 539 have RF as well as AF gain controls?
Ten-Tec: Yes.

QRPer: Will it offer front panel adjustable side tone for both frequency and volume?
Ten-Tec: Yes.

QRPer: Will it have user selectable tuning rates?
Ten-Tec: Yes.

QRPer: Will it have easy-to-set VFO A=B from front panel to work split?
Ten-Tec: Yes, just like all other Ten-Tec transceivers.

QRPer: Will the Model 539 have a keyer built in, and will it have memories?
Ten-Tec: Yes, it will have a built-in keyer, but no memories at this point.

QRPer: An attenuator? Available on the front panel?
Ten-Tec: You will have the ability to turn on or off a pre-amp. However, there will be no attenuator.

QRPer: That leads to my next question: one reader asked if the rig will have RF GAIN control rather than an ATTENUATOR, which is on the 516?
Ten-Tec: Yes, with our RF gain control.


QRPer: Will the rig offer a line-level audio-out jack independent of the AF volume control?
Ten-Tec: Yes, the connector is the same as the Ten-Tec Eagle.

QRPer: Computer control port? Computer controllability?
Ten-Tec: Yes, the Model 539 will have a USB port for PC control.

QRPer: IF out to connect to SDR Rx for band scope use?
Ten-Tec: This is to be determined.


QRPer: True FSK RTTY? Not forcing the use of AFSK.
Ten-Tec: There will be capability for a sound card device that can plug into the back for PSK and RTTY. At this point, it will be AFSK only.

QRPer: How about water resistance?
Ten-Tec: Let’s put it this way…if you get it wet, dry it off quickly!


QRPer: Good choices, even if they are extra cost plug-ins: Xtal and/or DSP?
Ten-Tec: This is the neat thing about this radio, Tom. This will be a reflection of the Eagle. We are going to give you a roofing filter in the first IF stage. There will be two additional slots for crystal filters. We will offer 6 kHz, 900 Hz, and if you want to, you could use filters from the Eagle as they have the same board. Additionally, it will have all of the DSP filtering the Eagle has. You’ll essentially have 3 roofing filter slots and over 100 DSP filters 100 Hz to 6 kHz in roughly 25 Hz steps for the first 120 or so.

QRPer: Will these be Ten-Tec proprietary, or may third-party filters (W4RT, etc.) be used?
Ten-Tec: Any third-party filter made to work with a Ten-Tec radio will work in the Model 539. The manufacturer would have to take the initiative to build the filter to match our radio. Inrad has a long tradition of working with Ten-Tec in this respect, for example.

Output Power

QRPer: How about easy power output control?
Ten-Tec: Yes. Selectable from 1 watt to 10 watts in 1 watt increments. Zero watts for CW practice.

QRPer: Can power adjust down to the QRPp milliwatt levels?
Ten-Tec: In its current state, the rig is 1-10 watts adjustable. That is something we could look at.


QRPer: Will the 539 be tested for RF immunity when used with portable (hfpack) type operation?
Ten-Tec: It is possible that these conditions could be mimicked during beta testing. We can say that all proper FCC immunity testing will be performed. Of course, it will meet or exceed all spurious emissions requirements.

QRPer: How is the rig cooled? Is it a fan that can be fully controlled, or is there a heat-sink–of substantial size to accommodate the rig when mated to the amp?
Ten-Tec: With the Model 539, heat is not a major issue. It will have a heat-sink, not a fan.

QRPer: Several readers emphasized the importance of minimizing the current drain on standby and receive. They felt this was the Achilles heel of the Argo V. Is this a consideration?
Ten-Tec: Current drain is a consideration, but we place the most emphasis in the following areas: performance, sound quality and ease of use. We will certainly take current drain into consideration, but will not compromise the radio’s performance in the process.


QRPer: Would you consider distributing through HRO or AES?
Ten-Tec: Ten-Tec is a factory-direct retailer. We do, however, have two very unique ways to assist future customers who cannot easily drive to our retail/factory store here in Sevierville, TN. Firstly, we are unique in the industry in that we give buyers 30 full days after purchase to use our radios hooked up at their home, to their own system and antennas. If, for any reason, they are not satisfied, we will take the radio back and give them a full refund less the shipping charges. Secondly, we have a very active Ten-Tec Ambassador program with ambassadors in literally every state of the US. Simply contact an ambassador and they will help you in any way possible to get a feel for our radios. We know of no other manufacturers or retailers who offer these options.

Model 418 Amplifier Questions

The Ten-Tec Model 418 100 Watt Amplifier on display at the 2011 Ten-Tec Hamfest. Click to enlarge.

QRPer: A QRPer would like the Model 418 to be easily interfaced with other QRP radios and kits with a drive level low in the one watt range. Is this possible?
Ten-Tec: This is a good point, and a strong point with the Model 418 amplifier. The Model 418 will be adaptable to any QRP transceiver out there.

QRPer: Will all modes be accommodated as well? (AM, CW, SSB, RTTY, PSK, FM), including those with full duty cycle?
Ten-Tec: Yes.

QRPer: For desktop use, one QRPer suggested TT could add the tuner into the amp, if there’s no room in the 539.
Ten-Tec: No, we would not put a tuner inside the amp.

QRPer: What are the minimum and maximum drive levels for the 418? One QRPer has a SDR project that will output 0.5 – 1.0 watts, but also would like to use it with a 516. Assuming that with the 539 output of 10w, it outputs 100w, but what might one get with one or two watts? Are there attenuators that could be switched out for this purpose?
Ten-Tec: Again, the Model 418 will work with any transceiver out there. You must keep in mind, though, that it will adhere to FCC regulations regarding amplifiers. As such, it cannot produce more than 15db gain. Five watts in will produce 100 watts out. If your transceiver produces more than 5W in—and that’s perfectly fine—the Model 418 attenuates, so that no more than 100 watts leave the amplifier.

General Questions

QRPer: In your view, how will the receiver compare to an Elecraft KX-1 or KX-3?
Ten-Tec: Honestly, we’re not comparing it to any radios out there. The Model 539 will be a Ten-Tec radio, as such it will be a performer, it will have excellent audio fidelity, and the Model 539 will be easy to use—at home or in the field. It is a continuation of the Argonaut legacy and has been in the works for quite some time.

QRPer: Finally, on the business side: Ten-Tec is successfully manufacturing in the US, keeping people employed in a profoundly strained economy while so much manufacturing has been relocated to Asia and the far east. How do you do it? How does Ten-Tec keep going, creating great technology instead of bending to these powerful economic pressures?
Ten-Tec: Let’s face it. These economic conditions are tough for any manufacturer and we’re certainly not immune to it. Though the amateur radio market is an active one for us, we also have military and commercial contracts. We also have an enclosure business. We’re well enough diversified that if one market suffers, we have business in other markets.

The Model 539 and the Model 418 will be designed, produced and manufactured here in Sevierville, Tennessee, in the US of A.

QRPer: Jack, John and Stan—I gathered these questions from hams who contacted me through and I also queried several email lists. I can say that there is a lot of excitement surrounding this radio—I sorted through and compiled these questions from literally a hundred or so. Thank you so much for allowing me to approach you with these questions and for your thorough answers.

Ten-Tec: Thank you, Tom, for the opportunity. This feedback is important and it’s our pleasure to provide it.

Post script

When I traveled last week to the Ten-Tec Hamfest in Sevierville, TN, and snapped a few photos of the Model 539 and 418, I had no idea that the response from my ensuing post on QRPer would receive the attention it did. It’s truly been extraordinary.  Immediately after making this post, questions about these two prototypes started piling up in my inbox.

I compiled these questions and approached several email lists to ask if they had questions. Again, the response was overwhelming.

I approached Ten-Tec with the landslide of inquiries. But, fortunately, Ten-Tec was up for the challenge, and I’m very grateful they were able to provide dedicated time to provide some answers.

While this remarkable rig cannot provide everything to everyone–and none can–my overall impression from the interview is that the Model 539 transceiver really will offer excellent performance characteristics at a reasonable price. Ten-Tec has proven with their Eagle, OMNI VII, and Orion series that the company is responsive to customer needs and updates firmware very readily.  This could be a winner.

I also came away from the interview with the strong sense that, though a lot of emphasis is now being placed on the Model 539, the Model 418 amp could be, in its class, the dark horse that finishes first.  Yet what would it run against? Indeed, I know of nothing else like it on the market. Speaking for myself, I have several QRP radios in both the shack and the pack that could certainly benefit from the extra watts it could provide, should conditions prove unfavorable during a rag chew.

You might just note that I’ll continue to keep in touch with Ten-Tec and provide any public updates here on Please subscribe to our RSS feed or follow us on Twitter.