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Showing posts with label AA1TJ. Show all posts
Showing posts with label AA1TJ. Show all posts

Thursday, July 14, 2011

Sputnik Madness! But was it CW? or AM?

Our worldwide team of Sputnik enthusiasts continues to seek out the elusive schematic diagram of the spacecraft's 20 MHz transmitter. American, Cuban, Russian and German radio amateurs are involved. Recently Bruce, KK0S, visited the Kansas Cosmosphere in an effort to get a look at the innards of Sputnik's "flight spare." The picture above is his -- it shows the Sputnik antenna connection. (More pictures from Kansas here: http://s747.photobucket.com/albums/xx120/trader_vic/Kansas%20Cosmosphere/)
There was bad news and good news from the visit: The bad news was that the spacecraft on display was a hollow sphere. The good news is that the internal parts --including the transmitter -- might be in storage someplace, just waiting for our reverse engineering. Stay tuned (to 20 MHz!).

Speaking of which, I have a question: OK so the crafty Soviets picked 20.oo5 MHz for some good reasons: Being so close to the WWV freq, it would be easy for hams and SWLs to find it with precision. In the November/December 2007 issue of "Break In" (from NZ -- thanks Jonathan-san!) ZL3DW notes that this frequency selection would allow a receiver set to exactly 20 MHz to "produce an audio tone plus or minus the Doppler shift without ever going through zero beat." But zero beat with what? Most of the receivers out there would not have had BFOs, right? So the Soviets wouldn't have been using ordinary CW, right? Were they using AM, with the beeps produced by an audio oscillator modulating the carrier?

Here is a update from our Chief Designer, Comrade Mike, AA1TJ:

I currently have a prototype for a simple "Sputniker" transmitter on the bench using a 1sh29b in the oscillator and a 1p24b working as the PA. As in the original, the input
DC PA power is 1watt. The crystal-controlled oscillator uses an inexpensive ESS 21.060kHz xtal. So far, all systems are GO.

BTW, here's an example of how inexpensively these lovely little tubes may be purchased. Oleg, RV3GM, and his pals might be able to do even better.

Although there are only so many ways one can build a two-tube, crystal-controlled MOPA transmitter, we'd still very much like to nail down the original transmitter circuitry. Bruce, KK0S and Peter, DL2FI are following up leads to that end.

Once we're a bit further along I'm hoping that someone will step-up to produce a kit. Actually, last evening someone raised their hand to ask if a kit were already available.

Dasvidania,
Mike, AA1TJ

Saturday, July 2, 2011

WOW! The Reverse Beacon Network


In the European dispatches of Mike AA1TJ I saw mention of this new thing called the Reverse Beacon Network. Then SPRAT shows up in my mailbox (HOORAY!) and I see mention of the RBN there. So this morning I figured I'd give it a little test: I called CQ on 40 meters using my Heathkit HW-8. WOW -- it didn't take RBN long to get me! See above. That's after only about 3 minutes of CQing.

This is a really amazing and innovative development. The network makes use of "skimmers" that use Software Defined Radios connected to the net to search for CQs. When they hear one, they automatically post the info on the web. It is sort of like WSPR, but it is aimed at ordinary CQ calls. Fantastic. Check it out. You will like it!

Saturday, June 18, 2011

AA1TJ: Hiking through Austria, Thinking about Sputnik



The Hero of the Hobbit Hole and Poet Laureate of QRP, Michael AA1TJ and his wife Vicki are hiking through Austria these days. Michael is on the air with a rig powered by one D-Cell battery. Now, I'd like to tell you guys that through some MIRACLE of electronics he sent us this video via that D-Cell rig, but it's not April 1. And even if it were April 1, I'd be reluctant to use that as my gag because, given Michael's high level of operating and technical skill, there is always the risk that he'd find a way to do actually do it!

Anyway, as he makes his way between ancient Roman signal towers and picturesque Austrian villages, Michael has been thinking (as you do) about the schematic diagram of the radio transmitter on the Sputnik satellite.

Gentlemen, we need this diagram. And it is not (GASP!) available on the supposedly all-knowing internet.

Here is Michael's message:

Hi Bill,
I've been thinking about "Sputnik Day" while hiking this past week or ten days. Bill, I think we've really got to do this. Many thanks for your help so far...the Kansas Connection is very tantalizing! I know you have a lot on your plate but if there is anyway you could move things along with the Kansas possibility it would be fantastic.

If we approach the museum in a professional manner...pointing out the historical necessity for properly documenting what they have, I can't see how they could refuse us. Next, we would need to assemble a team of technically competent (and appropriately diplomatic) amateurs to go in to photograph the transmitter and trace the schematic.

All the best to you and the family. Again, I think Sputnik Day could really fly...it has every aspect you could ask for...big history, home brew, QRP, contesting...

Any help or ideas from you would be most appreciated.
Tschuess, Mike, AA1TJ
Sent from my iPad

Is there somebody out there in Kansas who could take charge of this project? I agree with Michael: Essentially three steps:
1) Write to the
Kansas Cosmodrome museum seeking permission to examine the innards of the satellite.
2) Once permission is granted, one or two guys could go and take detailed photos of the transmitter and gather as much data as possible about the rig.
3) From these pictures, we could trace out the diagram.

Not only will we have what we need for Michael's Sputnik Day construction project, but we'll be making a real contribution to radio history.

We don't want multiple approaches to the museum, so maybe it would be best for anyone who is willing to do this to contact me first.

This should be fun!


Thursday, March 10, 2011

The Hobbit Hole

In the interest of preserving what I suspect will become an important piece of amateur radio history, I'm posting some pictures of the underground radio shack and workshop of Michael, AA1TJ.

Michael describes the facility this way: The shack is under two feet of snow at the moment, but from the surface it looks for the most part like any New England spring-box cover that you come across while walking in the woods. Only, when you lift this cover you discover Dr. Evil's secret underground radio laboratory, a re-creation of Hogan's Heros radio station, or what I affectionately refer to as the "Hobbit Hole."

The two of us burrowed down 13 feet, breaking up boulders the size of a VW Bug as we went. Aside from the pick and shovel work, I used both one and two-handed sledges along with an assortment of rock chisels and pry bars. Everything came up in 5 gallons buckets.

The lower-level slab used hand mixed concrete. The walls are 12" thick insulated masonry blocks; a Canadian-made product called, Sparfill, that's unfortunately no longer available here. We called in Ready-Mix for the concrete roof. The interior dimensions are a luxurious 2m square.

As luck would have it, I had just taken some photos of the interior for my pal, DL3PB. Please find them attached. Actually, in one bench corner you'll see the 2,400RPM AC induction motor and 400 pole stepper motor that I plan to use in the "Full Monty" version of the present project.


Mike has a wonderful posting on his blog today: http://aa1tj.blogspot.com

Tuesday, March 8, 2011

AA1TJ's Dream: No Tubes, No Transistors... ALTERNATORS!

Treat yourself today to an experience in radio enthusiasm and innovation: Go to AA1TJ's blog and read about his latest creation: The Schmidtschem. Michael begins his post this way:

I've dreamed and schemed, off and on, for the last twenty five years over the prospect of constructing a complete, high-frequency (HF) amateur radio station without the use of vacuum tubes or semiconductors... Having considered and subsequently rejected a number of esoteric possibilities, I eventually concluded that a system based on electromagnetic alternators was the most promising.

He has a prototype on the air, using it with a no-gain receiver, and he is making a lot of contacts. Check it out: http://aa1tj.blogspot.com/

Sunday, January 16, 2011

What should I do with this thing?

Pretty cool, don't you think? I found this among the stuff that arrived from storage. I must have bought it at a hamfest sometime in the distant past. Note the miniature TUBES. Note the place of manufacture: BEAVERTON, OREGON. The internal construction is beautiful, with good shielding between each stage. It has a nice AC power supply. I have no real need for a 2 meter converter... So, what should I do with this? It seems to have the potential to become a QRP transmitter. Or maybe a DC receiver? Or maybe I should just turn it over to AA1TJ for conversion into something really surprising and marvelous.

Sunday, December 12, 2010

A good radio morning at N2CQR

Today I had one of those really good ham radio mornings in the shack. My objective was to add one more amplifier stage between the balanced modulator and the power amplifier in my Roman WSPR DSB Direct Conversion transceiver. First I had to take the balanced modulator (trifilar transformer and two diodes in a singly balanced configuration) off the board and move back, closer to the AF input jack -- I needed to make space for the new amplifier stage. For that stage I consulted Doug DeMaw's books and Wes Hayward's EMRFD. I went with a feedback amp using a 2N3904 in Class A.

With coffee brewed and with my Drake 2-B tuned to the very congenial DX-60 net (75 meters AM on Sunday mornings), I turned to the junk box. It was like meeting old friends! I pulled out parts that Michael, AA1TJ had sent me. I pulled out others that had been sent by Jim, AL7RV. I got out my box of isolation pads that Jerry Felts, NR5A had sent in. Soon the parts were glued and soldered to a board that already had an AF amplifier designed by Roger Hayward, KA7EXM and a PA that is my "Manhattan-ized" version of Tony Park's SDR rig PA. At the center of the board is little Colpitts oscillator that I took from a WSPR rig designed by Gene, W3PM -- earlier in the week Gene had posted a comment on this blog saying he was pleased to see my call on his WSPR screen. I wonder if Gene realized that he was seeing the signal from an oscillator from his design! The laptop was provided by a listener who prefers to remain anonymous -- thanks OM! Nearby, a copy of "Lid, Kid, Space Cadet" by Jeff K1NSS provided encouragement.

The rig passed the smoke test so I moved it over to the operating position and put it on the air. I got immediate gratification: the WSPRnet map right away showed my signal (now around 200 milliwatts) being received all round North America. You can watch this LIVE by going to http://wsprnet.org/drupal/wsprnet/map Just plug N2CQR into the "Call" box and hit UPDATE.

I know that WSPR is not everyone's cup of tea, but I like it. It was fun to build this rig. While WSPR is almost exclusively a mode that uses store-bought equipment, I get a kick out of being one of very few ops using a homebrew transceiver in this mode. (Are there any others?)

Next steps: I need to figure out how to set up automatic switching (by the computer) from transmit to receive. And I want to make some PSK-31 contacts with this rig.

Thanks to all who contributed!

73 Bill

Sunday, December 5, 2010

More QRPoetry from AA1TJ

This is actually prose, not verse, but it has a poetic element to it. It is not for nothing that we have called Michael "the poet laureate of QRP." Must be all that time up on the mountain. Whatever the motivation, we're always happy to get his messages, and we always find inspiration in them:

On the topic of QRP power levels; for me it all stems from the pair of "100mW" walkie-talkies that my brother and I found under the Christmas tree one year. I thought it was magical that we could walk around the neighborhood and still talk to each other. Then one day my friend and I was messing around and I heard some lady's (CBer) voice all of a sudden. It took a moment to figure out that she was talking to me (my first and last CB QSO). We only talked for a few moments but it left me wondering how far it might be possible to communicate with such low power. The electronics magazines I was just starting to read showed massive boat-anchor transmitters; none of which appealed to me. For me the excitement was trying to see how far I could talk with my MPF102 oscillator on 40m; and later, a similar xmtr made from a surplus 2N697 that I happened upon. It was around that time I first heard about tunnel diodes; exotic devices based upon the (still) mystical notion of quantum tunnelling. Of course, I dreamed about building a tunnel diode rig...a dream that would take 35 years to realize...to which I owe a huge debt to Seab, AA1MY...dunno if he knows to this day how big of a deal it was for me; which is why I was especially happy to see his, "with childlike joy and wonder" comment. Ditto for me. Speaking of which, last I showed my wife, N4KGL/p's QTH on the map located on his site "Nov 23rd Lunch Time QRP". http://www.n4kgl.info/ We thought it was fun to progressively zoom out from the parking lot where he was operating yesterday. Right away the Gulf of Mexico appears. Of course, Vermont eventually comes into view. Scientific American that did a similar series of zooms in a book some years ago. It began with a couple lying on a blanket in a park. Some pages later you're staring back at this "pale blue dot" (to steal Carl Sagan's wonderful phrase). Something else comes to mind from Tom Wolfe's, The Right Stuff. Do you recall the passage where Lovell covers the Earth with his thumb? "At one point I sighted the earth with my thumb—and my thumb from that distance fit over the entire planet. I realized how insignificant we all are if everything I'd ever known is behind my thumb. But at that moment I don't think the three of us understood the lasting significance of what we were looking at." Dunno why, but QRPp feels a bit like Lovell's thumb. It gives me the same sense of vertigo displacement; a tiny signal sent from a tiny man located in a vast, oceanic, Universe. I remember saying so to my pal, Jim, W1PID, only last year in connection to my voice-powered CW transmitter. Hearing the dits and dahs return yesterday...looking at my puny transmitter...Wisconsin, Florida, Guadeloupe Island; bouncing these little ripples off the ionosphere...hearing the friendly replies...who would not be overwhelmed by the thought of it all? These little radios are just the launchers; pinkie fingers dabbed in the cosmic pool of Being. The Argentinian writer, Antonio Porchia, said, "Beyond my body my veins are invisible." Jim Lovell's veins radiated from beneath the thumb he so casually dabbed over the Earth. His veins radiated not just back to far away Earth - to everything that he loved - but in all directions; to places he'd never even dreamed of. I'd better sign now. I'm headed up to the mountain-top TV transmitter in a couple of hours... That's how it is here, Steve; QRO pays the bills, QRPp gives the thrills. :o) BTW, Dave, K1SWL, has already given a big thumbs-up to our RockMite contact! 73/72, Mike, AA1TJ

Thursday, May 20, 2010

Muntzing with Michael


Snappy title, don't you think? I think it could become a TV series, maybe if the Discovery channel someday gets into QRP and homebrew. In his QRP-L message about his latest rig, Michael, AA1TJ, said that he had "spent the morning 'Muntzing' G3XBM's, fine little XBM80-2
transceiver for the MAS (Minimal Arts Session) event." For those of you who don't recognize the verb "to Muntz", Michael is referring to one of the early manufacturers of TV sets, who, in an effort to reduce costs, ruthlessly went through his engineers' designs, throwing out every component that wasn't absolutely necessary. So I think Michael -- who I often refer to as the "Poet Laureate of QRP" -- has given us a new and very useful verb: To Muntz! (This comes in a month in which another very useful word was given to us: G3RJV's "socketry.")

Michael said, "I felt like the guy in the movies yesterday; throwing everything overboard that's not absolutely necessary in order to keep the Zeppelin/balloon aloft long enough to make landfall. :o)" The results speak for themselves. The schematic above and the picture below show Michael's entire transceiver. And he made a bunch of contacts with it.

One word of caution: Minimalist radio is not for the faint of heart. As the parts counts go down, the degree of difficulty for successful contacts goes up.

Check out Michael's page: http://www.aa1tj.com/Menos es MAS.html

Here's a picture of the rig:

Saturday, May 8, 2010

The Limerick Revolution

On the last podcast I mentioned a new PC board technique being pioneered by Rex, W1REX, out of Limerick, Maine. The Limerick technique uses cool-looking black PC boards with pads for the components. (The picture above is the kit version of AA1TJ's famed Reggie receiver.) Connections between the pads are via PC board traces within the board. I like it because it seems to provide the big advantage of our beloved Manhattan technique: you have all the parts and connections topside. Check out Rex's fine line of kits: http://www.qrpme.com/

Today G-QRP club announced the release of a Limerick kit version of G3RJV's Sudden receiver.
Take a look at the final product and the boards:

Very nice. Read more about this wonderful kit here: http://www.gqrp.com/sudden.htm

Go Limerick! Go Sudden!

Friday, April 9, 2010

Colpitts Mania! Two Rigs Under Construction

I'm really into Colpitts oscillators lately. I blame Gene, W3PM. He reminded me of the fact that these little one transistor stages can pump out the 7 dbm needed to drive a diode ring mixer. Gene sent me a note warning that I'd have to take special precautions to ensure stability, but I found that this circuit never strayed more than 20 hertz in the course of a full day of oscillating.

Above you can see my version of the Colpitts circuit that Gene has in his very nice WSPR transceiver. You can see the SBL-3 diode ring mixer above the oscillator in this picture. I still haven't decided on the audio amplifiers.

I'm working on a second Colpitts circuit. This one is for a QRSS transmitter, also for 30 meters. Here I took my inspiration from Michael, AA1TJ, who has been working DX with power levels similar to that of this little oscillator. Long-time blog fans might recognize this board, or at least the device that it was used in. This is the board from my "DaVinci Code" 30 meter frequency standard, so called because I used a paperback copy of the Dan Brown novel as insulation for this weird piece of test gear. With my Kempton Park Frequency counter working, I had no need for the DaVinci device. But the oscillator was a Colpitts, capable of pumping out 10 mW all by itself... I plan on building a Hans Summers-style multivibrator circuit to put a distinctive pattern on my QRSS sig. It should fit nicely on the same board. I have a case and a power source in mind: see below. See if you can figure out where I'm going with this.

Tuesday, March 30, 2010

AA1TJ on Polyakov, Scrounging Parts from a Wehrmacht Tank, QRPp Success

Caro Bill, FB on your 20mW DSB WSPR DX! I've never actually been on the air during the upside of a solar cycle. This is wicked exciting! Thank you for the nice write-up on your Soldersmoke Blog, OM. I heard back from Fabio this morning; he seems to be as excited as I am (please see his message below). Italy is my fourth DX contact and third country with 10mW. Two weeks ago I worked F5NBX twice and FM5LD once. Again, all great fun... I'm glad to hear of your interest in the Vladimir Polyakov's mixer. I can attest to Vlad's claim about its resistance to SWBCI. So far, I've used silicon and germanium diodes, MOSFETS, and even a saturating inductor for the subharmonic, commutating switches. I haven't mentioned it till now, but leading up to my Gigi regenerodyne receiver, I built Polyakov reflexed 40m receiver that was lots of fun. The RF input signal first passed through a simple BPF on its way to the cathode of a triode, grounded-grid RF amplifer. The amplified signal next passed through the Polyakov anti-parallel diodes. The resulting AF signal was then re-injected into the grid of the same triode (now working as a common-cathode amplifier). In typical "reflex' fashion, the same tube amplifies first at RF and again at AF. Looking at my notebook entry, I was able to "plainly hear" a 1.0uVrms signal and in a week of operation I hadn't noticed any SWBC breakthrough. Actually, the subharmonic mixer was well-known by 1976, but I'd never seen it used by hams at HF until Polyakov popularized the idea. Our Eastern European comadres took a liking to it right away but it took some time before it finally caught on in the West. By the way, I had a short email exchange with Vladimir a few months ago. I'm pleased to report he's a really nice fellow. He happened to mention that his first amateur radio transmitter was built using parts that he salvaged from an abandoned Wehrmacht tank. It seems radio components were extraordinarily hard to come by in those days. Amazing... Have fun, Bill! Mike, AA1TJ ---------- Forwarded message ---------- From: Fabio Ventrone Date: Sat, Mar 27, 2010 at 9:16 AM Subject: Re: IZ0PEC de AA1TJ/QRPp To: Michael Rainey Dear Michael, Many many compliments for your qrpp station! Really exciting to have qso in this conditions... It's actually the first time I can connect qrpp oversea... Unbelievable, something we can tell our friends forever!!! I was transmitting with 4 el antenna and something more than 100w. I will have to take back my 817 and try to call dx as you bravely did!!! Best 73 qsl Fabio de IZ0PEC 2010/3/26, Michael Rainey > Dear Fabio, > > Thank you for your patience in copying my signal on 20m CW this evening. I > had been calling DX stations for several hours but you were the only one to > answer. My homebrew rig has an output power of only 10mW (0.010 watts). The > distance between us is 8793km; nearly one million km per Watt!. The antenna > here is simply an end-fed wire. > > I am amazed that you heard my 10mW signal in Rome. It's fantastic! > > Again, thank you for patiently listening for my weak signal, OM. It would > not have been possible without your very kind efforts. > > Ciao, > Mike, AA1TJ

Thursday, March 25, 2010

Sunspot 1057 Doing Good Work for US!

I got up early this morning, and so did 30 meters. Take a look at the WSPR signal reports that greeted me (below). My 20 mW DSB signal was making the trip to Norway and the UK through most of the night. And at 0256 W1BW picked it up. A visit to the excellent spaceweather.com website reveals that this is probably the work of sunspot 1057. Rogerio Marcon took this picture of that sunspot on March 24 from his backyard observatory in Brazil. (This and a recent thread started by Chris Trask on QRP-L make me think that I NEED a solar telescope.)

My e-mail inbox also had evidence of good HF conditions. Take a look at this from AA1TJ:

IZ0PEC de AA1TJ/QRPp

Thursday, March 25, 2010 9:52 PM
From:
To:
f.ventrone
Dear Fabio,

Thank you for your patience in copying my signal on 20m CW this evening. I had been calling DX stations for several hours but you were the only one to answer. My homebrew rig has an output power of only 10mW (0.010 watts). The distance between us is 8793km; nearly one million km per Watt!. The antenna here is simply an end-fed wire.

I am amazed that you heard my 10mW signal in Rome. It's fantastic!

Again, thank you for patiently listening for my weak signal, OM. It would not have been possible without your very kind efforts.

Ciao,
Mike, AA1TJ

Wednesday, March 17, 2010

G.W. Pierce and the AA1TJ GiGi

Mike, AA1TJ, continues to provide the global solder-melting fraternity with large doses of QRP/homebrew inspiration. And, as usual, his latest series of messages to QRP-L contain interesting references to the radio pioneers who laid the ground work for his low power exploits. This time, it was G.W. Pierce.
-------------------------------------------------------
From AA1TJ on March 8, 2010:
Fellers,

It was an exciting QRPp afternoon here on 20m. It started off well
with a ten minute contact with G3MJX. Tony was running 5w to a dipole.
I'm still using the breadboard, two-tube, 250mW (Gigi) station that I
wrote about last week.

KB0PCI in Minneapolis was my next contact. Wayne was using 5w to an
indoor loop. I thought that was pretty cool.

Things seemed to be going so well that I felt the urge to further
reduce my output power. Dropping back to 56mW, I soon snagged Jack,
W7CNL. He's out in Boise with 5w and a five-element Yagi. It was a
great contact with 579/539 reports.

After we signed I resumed calling CQ. Sometime later I heard my call
coming back at me; always a happy moment when you're running QRPp. But
wait...he's signing DH1BBO...Holy Toledo!

With a pounding heart I sent off a 559 report. Olaf came back with a
529 for me, and get this...he says he's running 300mW to a windom! The
first round was an easy copy for both of us, but thing got a little
rougher after that. Still, we were able to hold it together through
the finals for a complete QSO.

Again, my transmitter circuitry is right out of 1928; a
crystal-controlled, push-pull oscillator using a single, 3A5 (a
twin-triode introduced by RCA in 1942). The receiver uses a second
3A5. The first triode forms a crystal-controlled autodyne converter.
The second stage is a standard regenerative detector driving the
headphones directly. My antenna is an end-fed wire at 35'.

Anyway, it was one of those QSO's that I dream about; QRPp on both
ends from start to finish, wire antennas at both stations and an
ultra-simple rig from the days of yore. It was Olaf's first QRPp DX
contact ever, and 57mW now stands as my lowest USA-to-Europe contact
power (230mW was my previous best).

As for working a 300mW German station with a receiver made from a
twin-triode; I think it's a testament to what these little
regenerative detectors are capable of. I was awestruck at the age of
12 or 13; having built my first genny. I love 'em no less some forty
years later as they truly are a beautiful technology.

73/72,
Mike, AA1TJ


From AA1TJ on March 3, 2010:
Bill,

Gigi worked AA7VW (running 5w to a Moxon) in Oregon today with 250mW.

I've been reading a bit of history here in preparation for my
presentation at MassCon next week. For example, I've traced the
crystal-controlled, push-pull transmitter (used in Gigi) as far back
as 1928. Cady and Pierce did their ground-breaking work on quartz
crystal-controlled oscillators in 1923, so it didn't take long for
hams to jump on this one. BTW, Professor George Washington Pierce
("G.W." to his friends) was a real character!

I send my best wishes to you and the family, Bill. The sap has just
started flowing here this week. It's Maple sugaring time in Vermont
again. Spring can't be far away now.

73/72,
Mike, AA1TJ

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

Here is a bio on Pierce: http://profiles.incredible-people.com/george-washington-pierce/

This all makes me want to reconsider my opposition to regens... Maybe they are NOT possessed.

Thursday, January 28, 2010

QRSSing again, AA1TJ's new page



As I mentioned earlier, computer problems have delayed the SolderSmoke podcast (don't worry, parts are on the way).  They have also knocked me off the WSPR system.  So I switched over to QRSS mode and am now pumping out about 20 milliwatts of upside down sloooooooooow FSK on about 10140050 Hz.  (Don't you like how in QRSS you find yourself giving the frequency not in kilos or megas, but in just plain Hertz?   If I get into a retro mode I may start giving them in cycles.) During daylight hours in Europe you should be able to watch my little signal arriving at ON5EX's station in Belgium.  Just look down on the right on this page for a live view of Johan's receive screen.


VA3STL has some good QRSS stuff on his blog:  http://va3stl.wordpress.com/



I noticed this morning that Mike, AA1TJ has moved and updated his very fine site.  Check it out: 
http://www.aa1tj.com/radio.html
Be sure to click on the link that lead to info about Mike mountain-top work site.  Like I said, truly the kind of job that Knack victims dream about.

Rumor has it that Dan's Small Parts is back in operation after a winter break.

Tuesday, January 12, 2010

AA1TJ: Reggies Rule! Diode Amps! QRP to the Max!



Whenever I find myself in need of some radio-inspiration, an e-mail from Mike, AA1TJ, seems to pop up in my inbox. This morning's message and the associated video (above) were especially inspirational. Mike was e-mailing Steve, WA1HFF.

Hi Steve,
Thanks for the message and the great QSO! I was running my one transistor transceiver that I call the Reggie. You can read about it on my webpage at

http://mjrainey.googlepages.com/reggie

My antenna is nothing to write home about; just an end-fed half-wave wire bent into an "EL" at 35 feet.

I've made just over 240 contacts with my Reggie in a little more than a year's time; working 19 states. My best (and only) real DX was the Bahamas. All of these contacts were made with no receiver gain on this end; just a pair of diodes fed by a one-transistor BFO, and onto the headphones.

A couple of fellows have built their own Reggies, so you might run into one on 80m now and then. I've made three Reggie to Reggie QSOs thus far.

Steve, last night I was trying something new; I ran a loudspeaker from an audio amplifer connected to my Reggie. What's unusual is that my audio amplifer was made from three, common power supply rectifiers (1N5401's). I'm not kidding! It's a nearly forgotten circuit from 1954 that I (re)stumbled upon a couple of weeks ago. It uses the phenomenon of PN junction charge-storage to produce amplification.

Last week I used two diode gain stages for a total power gain of 48dB to drive my headphones. Yesterday, I added a third diode gain-stage and connected it to a loudspeaker for shack-filling audio volume.

I made a video of last night's setup (the same setup I worked you with). You can see it at

http://www.youtube.com/watch?v=3DA07A6BLDg

Thanks again for the nice contact last night, Steve. You were armchair copy here! :o)

Best wishes,
Mike, AA1TJ

Here's a question for Mike: Can you build that kind of amplifier with homebrew point-contact diodes? If so, you'd be opening up the possibility of a homebrew solid state receiver with homebrew solid state devices. Oh man, this stuff makes me feel like such an APPLIANCE OPERATOR.

Friday, November 13, 2009

Final Report from the Maine Code Talker/160 QRP Rexpedition

Rex, W1REX, has a really nice article on this week's historic QRP expedition to the Maine coast. As you have read in this space, Michael, AA1TJ, challenged the mighty Atlantic with nothing more than the 15 milliwatts generated by his own voice. No joy this time, but we are sure that Michael will soon experience the same thrill felt by Marconi when that first, faint S was heard on the other side. Seab, AA1MY, overcame serious kite problems and fulfilled a long-held QRP ambition by working across the pond on 160 meters with less than 5 Watts. Congrats Seab! Congratulations to all the Rexpedition team members. It has been really fun to follow your adventure.

Read all about it here: (The link to the Rexpedition article is near the top of the page, but don't miss the wonderful kits that Rex is offering further below!)

http://www.qrpme.com/

Wednesday, November 11, 2009

AA1TJ Code Talker on the Maine Coast



Apparently no voice-powered transatlantic joy yet, but we all know it is just a matter of time. And I think this will be something completely new in radio history! Great try guys! Keep at it!

From W1REX last night:

We started about 8:45 am this morning, because AA1TJ was too excited to
wait any longer! He shouted into his #2 can for a couple of hours until
I thought he was going to burst a vessel....and I'm not talking about
one of the many passing by out on the ocean. We thought that we had a
2-way QSO a couple of times but the returns were simple lost in the
noise. Michael ran out of steam....or breath...and none of us old-timers
could cut the mustard..or soup...or whatever was in the can.

Seab, AA1MY, launched the kite last night prepping for an attempt at a
160m record. He intended to operate on 1.811 and cross 'the pond' with a
minuscule signal but the bridle broke on the kite and it sailed away....
It could be on the other side of the pond for all we know, as it was
never seen again. He launched a back-up kit tonight and had it up there
into the lower stratus-sphere but needed just a little more height as
there was still some antenna wire on the ground...but alas, the wind
came to an abrupt stop and the flying kite came to an abrupt just a
short time later.

So to sum up todays results: ZILCH!

We want to thank EVERYBODY who kept an ear out for us today and hope you
have the time and patience to try it again tomorrow morning!!

TOMORROW'S ITINERARY:

We have more wire up on 20m and will attempt another across the pond QSO
starting at 8:00AM local time or 1300 Zulu. Mike has to pick up his wife
at the airport in NH so the attempt will terminate long about 9:30AM
local time. So we have another 90 minutes to try for the record and YOU
have another 90 minutes to be a part of it. Listen in at 14.055 MHz
starting at 1300 hours. Put your good ears on and listen sharp... Hope
you hear us AND we hope to hear you hearing us...

Seab will take another stab at the 160m record (MAINE weather
permitting) probably around 700AM local time 1200 Zulu. He is
heartbroken that his dead-cert kit took a powder and dashed his dream.
Little back-up kite and a sightly altered antenna farm hopefully will
come through for him. Give a listen over there on the other side of the
Atlantic.

Monday, November 9, 2009

Transatlantic Team Heads to the Coast!

When it comes time to cross the pond, it seems only natural to head to the beach. That's what Marconi did (above we see his team struggling with a kite at Newfoundland). And that is what AA1TJ, W1REX, AA1MY and W1PID are doing today and tomorrow. Here is Michael's message to QRP-L describing the expedition. Good luck guys!

Some of the lads are heading over to the Maine seacoast on Monday
morning for what we're calling a "Rexpedition." W1REX was kind enough
to secure the use of his family's beachfront camp for us for a couple
of days. He explained the urgency to them, saying, "...a bunch of
radio-heads want to talk to Europe with the equivalent of a cellphone
with a dead battery."

Rex, Seab, AA1MY and Jim, W1PID, are going to arrive early on Monday
to begin putting up the antennas. I plan to show up in time for lunch;
hopefully after all the hard work is done. Seab wants to erect a pair
of half-wave phased verticals on 20m. I think the plan is to lift a
160m antenna using one of Seab's big kites.

Our hope is to cross the pond on both 160m QRP and with my
voice-powered 20m transmitter. The weather forecast looks great at
least through Tuesday. My "Code Talker" will be rockbound on
14.055MHz; same as last Thursday. We'll begin the voice-powered 20m CW
attempt the first thing on Tuesday morning (11/10/09). Again, the goal
is to span the Atlantic, but as always, I'll be very pleased to work
anyone that hears me.

By the way, last Thursday's voice-powered operation on 20m was a great
success. Altogether, I worked four stations and received one SWL
report. The best DX was W4FOA in Chickamauga, GA; a distance of
923miles. Tony reported that my 15mW signal was "an honest 579". W4OP
- located one hundred miles to the north of Tony - handed me the same
report and followed up with an amazing recording (you can hear it on
my website). Later in the day I received an email from AD5VC. Dana
reported that he clearly copied my callsign while listening on the LSU
club station (K5LSU) in Baton Rouge; a distance of 1375miles (nearly
half the distance between the Maine coast and London, England).

I thought these were remarkable results for 15mW into an endfed wire
at 35 feet. It makes next week's attempt from a saltwater QTH, coupled
with the low-angle of radiation with a spot of directional gain all
the more exciting.

So please keep us in mind come next Tuesday morning. I'm guessing Seab
will be operating 160m QRP on both Monday and Tuesday evenings.

Thank you,
Mike, AA1TJ

Sunday, November 1, 2009

Crossing the Pond... with the power of your voice

Michael Rainey, AA1TJ, has his eye on the North Atlantic. He's been thinking about maritime horns, and how far they could reach. He's built another kind of horn. I'm pretty sure that this one will soon take his voice and -- using ONLY the power of that voice -- send it across the mighty Atlantic. That's a pretty astonishing horn!

Yesterday Michael put a really nice message up on the QRP-L list. This is the kind of message that has earned him the title "Poet Laureate of QRP." Here is an excerpt:

I'm currently sitting at a desk on top of Vermont's highest mountain.
In the far distance I can see the Presidential mountain range of New
Hampshire
. Roughly twice as far away is the Atlantic Ocean. The other
night I spoke into a tin can, and the power of my voice carried a
message to the Maine seacoast where K1MPM heard me as clear as a bell.
I think this is absolutely magical. The present prospect of blowing
into a tiny horn and having this pittance of exhaled energy carry a
message back to England - when the bone shaking horn on the old Queen
Mary
couldn't carry to the horizon - is nearly beyond comprehension. I
know this is how everyone of us feels when we operate QRP.

Read the rest of Michael's message here:
http://mjrainey.googlepages.com/lavoixdesoc%C3%A9ans
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