Hunting Foxes With QRP

For those of us that enjoy CW as well as QRP operating, the Winter QRP Fox Hunt nights make for an exciting combination of both interests.




The QRP Fox Hunt is an operating event during which low power (QRP) stations or "Hounds", attempt to make contact with specific QRP stations designated as "The Fox".

Spanning a twenty week period from November to April, each week sees two Fox Hunt events ... one on Tuesday evening and another on Thursday evening. The Tuesday night event sees the Hounds go hunting on 40m, while on Thursdays, the move to 80m, for an even greater challenge.

For each evening, there are two assigned 'Fox stations', usually one in the east and one in the west. The object of the hunt is for the hounds (you and I) to find and work the fox ... both foxes if you can, as bagging both is the ultimate goal. This all sounds pretty easy except for the fact that all foxes and all hounds are limited to 5W output or less, and therein lies the fun! If you have never heard a pileup of QRP stations, it is worth tuning in just to listen ... a multi-station cacophony of QRP signals, all around 559 or weaker ... it's not your typical kilowatt-laden ear crushing pileup!

The 40m foxes will be found between 7030 and 7050, while the ones on 80m will be between 3550 and 3570 kHz. Most foxes make a habit of working split, usually listening 'up 1', so once you find the pileup, the fox is easier to locate.

The hunts begin at 0200Z and run until 0329Z ... early evening here on the west coast and mid-evening out east.

Complete rules and a 'Fox Hunt Primer' may be found on the QRP Fox Hunt home page here. For discussion of the individual events and soapbox comments, join the QFox ioGroup site here or join the chat in Facebook's QFox QRP Foxhunt Group.

If you're in search of some challenging week-night operating fun, you may just find what you are looking for with the bi-weekly QRP Fox Hunts. Working both foxes is not as easy as it might sound and is an excellent test for your antenna system and of your CW operating skills. Come and join the fun this coming Tuesday ... no special hunting permits required!

630m Transverter Project

I've ordered parts from Digikey for the summer workbench project, a 630m transverter. With the nice 630m WSPR signals received here from Roger (VK4YB) this spring, I think it might be possible for us to work each other using JT9, if the path continues to improve over the next few seasons. On more than one night, Roger's signal was at JT9 QSO levels and had we been on a schedule, a QSO may have happened. Roger's signal was peaking late in his evening, which for me will require making schedules in the wee hours of the morning.

I've been wanting to build another SMD project for some time since making a little SMK-1 40m transceiver several years ago. This was a very inexpensive kit put out by the NorCal QRP Club as a way of introducing SMD construction techniques to beginners. I found working with the 1206 sized parts (basically the largest ones commonly available) to be fairly laborious and would only solder a few parts at a time before setting it aside for the next day. I think my frustration had a lot to do with my positioning and soldering methods and I'm anxious to try doing it with a more refined technique. As I recall, there were 72 SMD components on the board and it took me a couple of weeks to finish it all.

My SMK-1 40m SMD transceiver

Although I was dreading the initial smoke-test, since troubleshooting would likely be a challenge, the transceiver fired-up with no problems and I made dozens and dozens of contacts with it. My QRP logbook indicates 27 states were worked with the little 350mw transceiver. It looks like this kit may still be available from Pacific Antenna but I have not confirmed if that's the case.

The parts I have ordered are also 1206 sized but the older I get, the smaller these things seem to look. The transverter will be based partially on the popular G3XBM circuit but will eliminate the PA. Instead, I'll just use a few volts of the transverted squarewave signal and a doubler, so that I can feed the signal directly into my present homebrew amplifier which uses two switching FET modules into a power combiner. Hopefully this system will let me run several of the non-linear digital modes such as WSPR, JT9, JT65 etc.

My 630m PA

As a way of getting back into the SMD-soldering groove, I have ordered and now received, an "SMD Practice Kit" from E-Bay ... a real bargain at $1.78!

courtesy: Tradeworld2105

Although there are many similar practice kits being offered on E-Bay, this was the only one I found that had two IC's to practice with ... all of the others had just one. Since the transverter's doubler circuit has an IC chip, a couple of practice opportunities will be helpful. My only hope is that I don't run out of SMD steam with the practice board before getting down to the actual transverter board.

As soon as the parts arrive from Digikey, I'll start designing the transverter's PCB ... but with all of the usual distractions of summer, as well as trying to maintain vigilance on the magic band once again, my summer project may not progress as quickly as I hope.

All of this assumes that my old eyeballs hold out as well.

Tuna Tin Fun

I was doing a little housekeeping in the shack this past week and ran across small piece of  anti-static foam with a transistor sticking out of it. It was the transistor from my Tuna Tin II final amplifier's stage ... the actual transistor that I had used to 'Work All States' on 7040KHz using my Tuna Tin back in 2000. Looking at it in my hand brought back a lot of wonderful memories from the fall of that year when I spent so much of my time looking for new states.

Like many others at the time, I was swept up in the second 'Tuna Tin revolution' when the NorCal QRP Club released a very inexpensive kit for the Tuna Tin II. It turned out to be the best $13 I had ever spent on ham radio bits as it brought me so much operating fun while making many new acquaintances in the process.

I recall the afternoon that I completed the kit ... attaching my antenna and calling 'CQ' on 7040 with a hand key plugged into the Tin. My afternoon call brought an immediate response from a station in Oregon who gave me a 579 report! Needless to say I was elated that it's ~360mw had done so well.

Over the next few days I worked a few more stations in the western states even stretching out to northern California and had pretty much decided that most of my QSO's with it would be fairly short range ... until the pre-dawn hours of August 6th when my hand-keyed 'CQ' was answered by NØTU (Steve), in Colorado! We had a nice solid ragchew until we ran out of darkness but the contact had given me re-newed optimism. If I could get a decent signal into Colorado, then perhaps I could actually work further afield ... maybe it was even possible to work all 50 states!

With that, I set myself a goal of trying to work them all. Although my 40m half-sloper was well matched and had proven to be a good performer in the 40m pileups, it only had four buried radials. The first thing I did was to bury another 30 radials around the base of the 48' tower, hoping to lower my ground losses as much as possible. With just one-third of a watt, there was no power to waste.

Back in those days, I was still working and could only get to the Mayne Island QTH on weekends. With the Friday night ferry arriving at around 8PM, by the time the woodstove had been fired-up and dinner taken care of, I very often didn't get to the Tuna Tin until around 11PM. As it turned out, the late hour operation worked out well and it didn't take long for my state total to climb. The toughest states were the New England '1's and as I neared the end, I still needed several. In late November, 40m revealed its magic-side and an early-evening 'CQ' brought replies from three W1's, all at once, each one a new state. Finally, in early December, I worked Wyoming for state number fifty!

The fifty QSL's were duly gathered and  sent to the ARRL for an official "WAS" award. Although there was no special endorsement for the Tuna Tin, other than for 'QRP', there was a nice note about it in the 'ARRL Letter' as well as in QST:

First Tuna Tin 2 WAS claimed: When the Tuna Tin 2 low-power transmitter article appeared in QST in 1976, its author Doug DeMaw, W1CER (later W1FB), envisioned it as a weekend project that could be used for short-range contacts.
Now, a quarter of a century later, a Canadian amateur has claimed the first Tuna Tin 2 Worked All States Award! Steve McDonald, VE7SL, got caught up in "Tuna Tin 2 Mania" and bought one of the popular TT2 kits. After working about 30 states with the little rig, WAS suddenly seemed plausible. McDonald realized his dream several months later when he turned in his cards for WAS. All contacts for the award had been completed while he was running about 400 mW from a Tuna Tin 2. As far as the ARRL awards folks know, this marked the first time WAS was achieved with a Tuna Tin 2--although there is no special endorsement for having done so. "Doug DeMaw knew in his heart that the rig would be useful and popular, but I don't think he ever envisioned that this little transmitter would still be working its QRP magic over 25 years after it first appeared in the pages of QST," said ARRL Lab Supervisor Ed Hare, W1RFI--himself a QRP and TT2 aficionado who has promoted the Tuna Tin 2 Revival and was McDonald's Connecticut contact for WAS. Congratulations to VE7SL on a tremendous operating accomplishment.--Ed Hare, W1RFI

Holding the battle-scarred 2N2222 in the palm of my hand reminded me of just how much excitement can be had with just a few simple parts and the magic of radio.

Inexpensive Kit From China

courtesy: http://www.banggood.com/

A recent posting to the GQRP Yahoo Group brought my attention to another inexpensive offering from China. This time it's Bangood's complete "Pixie" type 40m QRP transceiver for the incredible sum of $4.16 (U.S.)! The price includes all components, a nicely silk-screened PCB and free shipping. One really wonders how it is possible to make any profit with such an offering but it obviously is. However, all may not be what it seems. One purchaser, IK1ZYW (Paolo) who built the kit, described his findings in a recent blog posting of his building experience.

In spite of the problems noted above (with some now corrected), the kit still seems a bargain, if one takes the necessary care with construction.

Playing with QRP can often provide ham radio's best "fun for the money" as DX- capable transmitters can often be built for just a few dollars. I vividly recall the fun I had one winter while pursuing the first-ever Tuna Tin W.A.S. endeavour on 7040kHz.

I made many new friends on 7040 that winter and every weekend many of them would listen-in or call to see how my progress was going. The highlight of the adventure was late one Saturday night when I had three New England stations all answer the same CQ ... what amazing fun for a handful of parts at less than $10 ... not including the cost of a can of Tuna!


The little Pixie kit offered above has a power level fully capable of W.A.S. on 40m and with the decrease in solar conditions, 40m will just keep improving. If you purchase and build one of these kits, please let us know how your experience went. The 'interesting' construction notes may be found here.

VE7BPO Homebuilder Web Files

The recent closure of Todd's valuable site has resulted in the entire data from there now being mirrored at two locations in .pdf format. It's all there, complete with all the schematics and photographs from the original site ...and is very easily searched.  The file is about 40Mb and consists of 945 pages!

• Jason, NT7S has posted the file here.

• Steve, VK2JA has posted the file here.

If you missed it earlier, Todd's new blog is slowly starting to take shape and by the looks of it will soon be running full-speed ahead.

One More Winter For The Tri-Tet-Ten?

I originally built what I called the "Tri-Tet-Ten" to  test out a long-held idea of actually working Europe on 10m, using just a single-tube tri-tet oscillator and a 40m crystal. I had no idea what amount of power might be obtained on 28MHz from a single 6L6 crystal-controlled oscillator, quadrupling from 40m to Ten. After building several configurations as well as trying five different tube types, I was pleasantly surprised to end up with almost five 'clean' watts of 10m RF on my 40m crystal's 4th harmonic! I suspected that the tone would be unusable but the tri-tet proved to be surprisingly good at isolating the oscillator from the output stage. Although chirpy, the signal is indeed usable and somewhat reminiscent of what so many 10m CW signals must have sounded like at one time.

Having completed the transmitter just in time for Cycle 24's hoped-for great 10m conditions, it turned out that only a couple of one-week periods over the past three winters where good enough to reach Europe. During the two "double-peaks" I worked many dozens of Europeans, all of them in response to my crystal-controlled CQ's, mostly on 28.042kHz.



Courtesy: http://www.noaa.gov/

Nobody was more excited than I, the first time I heard a reply from Europe....it was from G4RRA who, as fate would have it, recorded my signal on that early October morning.

There were a few mornings when I had long pileups and worked Europe for several hours, most of the time shaking my head in disbelief that such a simple transmitter could provide so much DX pleasure...but really of course, it was mostly the great performance of Ten....the "other magic band".

I really doubt that 10m will once again support European conditions good enough for my one-tuber but it's still fun to work the U.S. With Cycle 24 on the decline I was happy to see that F2 has returned to Ten once again and this week I sparked-up the tri-tet to enjoy the propagation.

My chirpy return to the band produced many enjoyable QSO's..... NG2T (NY), KD8IFJ (MI), K9DP (IN), KA2MLH (NY), W4NA (VA), N4OW (FL), K8NS (FL), N5AF (TX), WA5AFD (OK), K5TIA (TX), K9DX (IL) and VE3IKV/m, boldly travelling along the freeway at 120kph!

So....if you hear a chirpy CQ just a smidgen below 28.042, please.... give me a call!

Will I be lucky enough to squeeze out one last winter of tri-tet fun before having to move down to 15 or 20m? Time will tell....but somehow it won't be quite the same as riding that delicate 10m ether over the pole to Europe, on just one tube.

Planting Homebrew Seeds

Over the past few months, several members of Yahoo's "qrp-tech Group" have been busy homebrewing their own versions of "The Ugly Weekender", a QRP transceiver originally designed by Wes, W7ZOI, and published in QST of August, 1981.
It has become one of the Groups "sandbox" projects, spearheaded by Chuck, K7QO.

A recent group post by Chuck has planted a new seed for the next sandbox project and it seems to be garnering much discussion:

My idea for the AM BC all transistor radio build is to
celebrate the 60th anniversary of the transistor radio.
Let's not over engineer this and get crazy. BC band only.
4 to 7 transistors. No ICs, since we didn't see ICs in the
early radios and they were a while away from being used.

This is a volunteer project, i.e. you pick and choose
what you want to do. You can use modern components
for your build, but I'm personally going with the simpler times.
By that I mean I'm not going to use an LM386 or other audio
IC and no NE602 mixer, etc.

If you google for 'AM broadcast transistor radio', you will get
link to a large number of schematics. For now, let's all wade
through them and in Sept see if we can find one that might
be a good group project to share and build together. This
for the purpose of learning something and sharing information.
Help the new guys and girls who want to try something different.

I have some 455KHz ceramic filters that I plan on using in place
of the IF transformer. The old radios used a 600 ohm CT audio
transformer to get down to 8 ohms for speakers. I'm going with
ear buds, so may get around the weight of the transformer. Time
will tell.

So, start doing some research to see what gets your interest in
doing this. I know that we all tune into the AM band, it will not be
like the old days of the old programming. Probably a lot of
religion, conspiracy nuts and other talk shows.....

------------------

As a side effect of this project:

Transistor theory books. I found vol 1 and vol 2 of the Sams
series. I put these on < http://www.archive.org > Just go
to the site and search for 'transistor fundamentals' and you
will see Vol 1 by Robert J. Brite and Vol. 2 by Charles A. Pike.
There is a Vol 3 and Vol 4, but I have had no luck in finding them.
Let's hope that some one will put them at archive.org for
preservation. Let us know.

We could, on the side of the AM build, get a study group to
help newbies learn transistor theory and circuits for building
some simple stuff. Wind up with some useful toys and learn
all about transistors in the process. That is if we get enough
interest.

Is there a good online course on transistor theory with labs?
There are some newer books on transistors that might be
candidates for a study group.

chuck, k7qo



Early Transistor Ad - QST March 1953

The world's first 'pocket transistor' radio was sold in 1954 by Regency.



 1st Pocket Transistor

To read more about the fascinating history of the 'transistor radio' and the Regency in particular, visit Steve Reyer's Website.





It's wonderful to see such interest in the art of homebrewing and it will surely be fun to see the end results of Chuck's latest seed planting.