Chitika: QRP

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Look at the drawing above. That is the banner logo of Rod Newkirk's column in QST magazine. For many years Rod regaled us with exciting reports on the activities of intrepid foreign radio amateurs, transmitting from exotic locations using ingeniously devised homebrew radio equipment. Look at the picture on the left side. See the palm trees? See the thatched roof shack with the dipole antenna? Well, that's pretty close to what it was like for me out on the Samana Peninsula in the Dominican Republic last month.

I set up the station under the thatched roof in this picture:

The red pins mark the spot:

Here I am, tuning the rig while looking across Bahia Rincon:

The rig was my Azores-built, oft-modified, NE602-based, ceramic resonator DSB transceiver with a recently added India-designed BITX IRF510 RF amplifier chain. A little article I wrote about the ceramic resonator VXO was featured in SPRAT 127. My antenna was a half wave dipole strung up in the thatched roof. Power came from 10 AA Batteries. So this was the Double A, Double Sideband, Dipole DX-pedition.

I had given some thought to building an SSB rig for this trip, but because of the efforts of Peter Parker, VK3YE, I felt compelled to take a DOUBLE Sideband rig with me to the beach.

Here is an old (2006) video on the rig. The power amplifier has been significantly modified:

Here is some more information on the rig, including a schematic for the receiver and the SPRAT article on the Variable Ceramic Oscillator:

http://www.gadgeteer.us/PORTABLE.html

Here is the log book for my contacts.

17 DECEMBER 2014

W1JPR PAUL MT. DESERT ISLAND MAINE

8P6AE (BARBADOS) COULD BARELY HEAR ME, BUT GOOD QSO

18 DECEMBER 2014

N4USA DAVE IN FLOYD, VA. FAIRS NET. (KK4WW.COM)

KE4UGF DON ALSO FAIRS, NICE GUYS. FUN CONTACTS!

KA4ROG ROGER NORTH OF ORLANDO

19 DECEMBER 2014

WB2HPV GUIDO TALKING TO ITALIANS EVERY MORNING FROM WAYNE NJ. HE HAD TROUBLE HEARING ME.

CONDITIONS SEEMED POOR, BUT I WAS HEARING AUSTRALIAN STATIONS

W8GEO GEORGE IN THE INTERCON NET. HEARD ME. ALSO ON INTERCON: KA4AOQ AND 6Y5MP (JAMAICA) ALSO HEARD ME.

N4PD PAUL

W3JXY/4 NAT IN KEY WEST

N1FM TOM, NORTH OF MIAMI SOLID QSO.

KM4MA PAUL IN ORLANDO WITH MARITIME MOBILE NET.

20 DECEMBER 2014

NA2LF LLOYD IN NY

WB8YWR JIM IN DALLAS

KM4MA.

W1AW/3 IN MARYLAND (TOOK ME A WHILE TO GET HIM)

21 DECEMBER 2014 NICE 4 WAY SPANISH LANGUAGE QSO:

KI4PZE MIGUEL

CO8OT JUAN IN SANTIAGO DE CUBA

WA4RME RAFA IN CHARLESTON S.C.

C08KB MARCO IN CUBA

Here is a short video showing the station and the location. Note the little birds (Golondrinas or Swallows) flying by. They nest in the thatched roof. They often got confused and flew inside the house. Billy and Maria rescued many of them. Whales breed in this bay in January and February. There are also manatees. It is really a beautiful place.

There were obviously other attractions (!) so I didn't spend a lot of time on the radio -- just a half hour or so every now and then. But it was really very satisfying to carry this little homebrew device with me, set it up in this amazing place, and use it to send my voice across mountains and hundreds of miles of ocean. I built this rig in the Azores and have used it in the UK, France, Italy and the Dominican Republic. It contains circuits devised by members of the British QRP club and by my friend Farhan in India. The ceramic resonator circuit is something I cooked up on my own. The microphone is from my old Sony Walkman and the pen that serves as its support is from that wonderful magazine "Electric Radio." In short, there is a lot of soul in this little machine. And it was a lot of fun to take it to the beach.

Thanks to Elisa for finding us this wonderful place. And to Rod Newkirk and QST for the DX inspiration.

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htmOur coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmokeOur Book Store: http://astore.amazon.com/contracross-20

Don ND6T has been helping us come up with a good simple low pass filter for the MMM (Steve Smith and the FCC insist). At the end of one of his e-mails, he shared this QRP Colorburst gem:

Be prepared to be occasionally amazed. Back in the late 70's I worked all over the western U.S. with under 1/2 watt. Regularly. Even a QSO with a UA0 (Siberia) with under 1 milliwatt, he having answered my CQ! I was seeing if I could "get out" using a single "D" cell flashlight battery that was too weak for the flashlight. All using a colorburst crystal. Oh, and a dipole 100' high stretched over a creek.

73/72,

Don ND6T

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htmOur coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmokeOur Book Store: http://astore.amazon.com/contracross-20

Wow, beautiful job Bruce. I was hoping that a check of the Reverse Beacon Network would reveal that someone had heard you, but no joy. Keep at it. You may become the first CLA member in this round to make a contact.

Bill -

Hello from the Midwest chapter of the CLA. Here's pix of my just completed Michigan Mighty Mite. Nothing was purchased specifically for this project. It was put together using only parts already on hand. The only previously unused parts were the front panel sockets and one resistor. The rig uses a 2N2219A transistor salvaged from a junked industrial control board and a color burst crystal that actually first oscillated in a tube-type color TV some 40 years ago. Loading into my ground-mounted vertical, this MMM seems to be most stable at a draw of 87ma at 12.6 volts. The arithmetic seems to work out at somewhere around 650mw into the ether. I called for about half an hour around 2300Z, but got no takers... it was still pretty early for 80m and I had an extremely high local noise level. The rig seems to run about 1khz high. I'll give it another go this weekend.

72 - Bruce - KK0S.

A thing of beauty! Check out the key!

What a great diagram. Schematic included!

http://www.sm7ucz.se/MMM/MMM.htm

Remnants of mine

Steve "Snort Rosin" Smith's

More on all this:

http://soldersmoke.blogspot.com/search?q=michigan+mighty+Mite

From a Facebook Post by Mike, AA1TJ:

Made 7 contacts with this tiny transceiver on 20m CW today with an RF output power of 10milliWatts. Five were stations in Georgia (GA QSO Party). The 6th was a regular QSO with a guy in Mississippi.
I answered a DX station calling CQ at 2230Z. Hearing nothing in response, I sent my call sign a half-dozen times anyway. More silence. As I was reaching for the knob to QSY he suddenly returned my call! ...Carlos, CT1BQH northeast of Lisbon, Portugal (that's him in the second photo). I was only 329 on his end but we kept it going for three minutes!

FYI: the transmitter (top circuit board) begins with a 3.58MHz ceramic resonator VXO (a 2N706 from the early 60's). That drives a push-push frequency doubler built around another 1960's-vintage, 2N2644 (obsolete stock from atop Mt. Mansfield, kindly given to me by Rich at Vermont Public Television). On receive, the 7MHz energy is routed via a DPDT relay (the orange rectangle) to the sub-harmonic (Polyakov) mixer located on the lower board. One stage of AF amplification is provided by a 2N333 that came off the GE assembly line in November of 1958. The DPDT relay is keyed directly. On transmit the 7MHz energy feeds a second push-push frequency doubler to produce 10mW at 14MHz (all spurs -35dBc, or less, with only the output resonator). The relay also switches the antenna between the transmitter and receiver.
Gosh, that was fun!

CT1BQH

Wow! Check out the latest rig from PY2OHH, the Wizard of Sao Paulo,

http://py2ohh.w2c.com.br/trx/pititico/pititico.html

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htmOur coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmokeOur Book Store: http://astore.amazon.com/contracross-20

FIXED! Following up on suggestions from Tony Fishpool and from Roy Morgan, I put a 10 ohm resistor between the two supply lines and put 100 uF caps to ground at either end of the resistor. I can now operate the receiver at high AF gain (no problem running a speaker) without the KLUDGE of two power supplies. The RX sounds great. I will soon match it up with the equally awesome Tuna Tin 2 for 1976 QRP EXTRAVAGANZA.

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htmOur coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmokeOur Book Store: http://astore.amazon.com/contracross-20

I didn't plan on doing this. I didn't even really want to do this.   I've become a phone guy -- I'm not into CW anymore. I figured I'd just finish the Herring Aid 5 receiver and settle the score from 1976 and that would be it. But everything I read about the Herring Aid 5 included references to the iconic Tuna Tin 2. Obviously I was also under the strong influence of my late February encounter with the original TT2 at the Vienna Wireless Winterfest. That Mojo is powerful stuff!   Then my wife brought home this can of Russian tuna. The dimensions were perfect. Then I looked in my junkbox and found 40 meter CW crystals. That was it. I had to do it.

I built mine Manhattan style, using several of W1REX's fantastic Me-pads.   I also used as the final a transistor that Rex gave me at Winterfest. Thanks Rex. Soul in the New Machine.

I'm getting about 200 mW out. I;m on 7030 kHz and 7040 kHz and 7110 kHz.   I have the TT2 up with my Drake 2-B (Herring Aid 5 integration will come later). I can feel the Mojo.

I just had my first contact with the TT2: I called CQ on 7110 and AB2RA came back. Jan was running 20 watts from an old 807 rig, listening with an old Hammarlund. So it was HB transmitter and vintage receivers on both ends! FB!

It happened at the Vienna Wireless Society's Winterfest Hamfest today in Northern Virginia.
That is Doug DeMaw's original Tuna Tin.
This may be the first time TT Mojo has been given to a phone rig.
Doug DeMaw would, I'm sure, approve.

Thanks Rex!

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htmOur coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmokeOur Book Store: http://astore.amazon.com/contracross-20

Last night I called CQ on 20 CW (with my Arduino keying the homebrew transmitter!) and was answered by Mark, WA0RBR. I Googled the call and found that Mark is quite a homebrewer. He wrote a nice series of articles for 73 magazine in the early 80's. Here they are:

http://mikeyancey.com/73mag/listauthor.php?Author=WA0RBR

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htmOur coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmokeOur Book Store: http://astore.amazon.com/contracross-20

Chitika

A Thatched Roof, Some Palm Trees, A Dipole, and a Homebrew Rig

Some Colorburst QRP Encouragement from ND6T

Midwest Mighty Mite from KK0S

Swedish Mighty Mite

AA1TJ Crosses the Pond with 10 milliwatts

PY2OHH's New Super-Minimalist (11 Component!) QRPp Transceiver

Herring Aid Motorboating STOPPED!

I Too Built a Tuna Tin 2

Tuna Tin Mojo Transferred to BITX17!!!!!!

Words to Live By...

WA0RBR's Fun-Rig

AHMED HASSAN MOHAMMED

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