Regens: A Complex Relationship; AA7EE's WBR

Bill -

I've been following your blog for a while now and am moved to let you know of my recent experience with regens, a subject that I know is dear to your heart or perhaps, more accurately, the basis of a complex relationship!

Anyway, the last time I built and owned a regen was as a teenager in the UK in the late 1970's when I had a one-tube HAC Model DX one tube regen. Recently I've been looking for a fairly simple receiver to build that would

receive CW and SSB on 40M, as well as AM. I'm developing an interest in AM on 40, a rather impractical mode in some ways, but one that I have an attachment to. A regen seemed an obvious choice, so after seeing the

reprint in "More QRP Power" of the QST article describing N1BYT's WBR regen, I decided to have a go at it.

In short, I'm so glad this was the first regen of my adult life. It is sensitive, suffers no hand-capacitance effects, has very little radiation from the antenna port due to the oscillator tank circuit being in a Wheatstone Bridge arrangement,

no microphony and to make things even better, is very stable in frequency. I can set it to a net or long-winded CW QSO and it stays there with no easily discernible drift (after a short warm-up period of course).

I know you're probably aware of this receiver, but have you tried building one? I think you'd be pleasantly surprised.

The blog post about my version of this great little receiver is here:

http://aa7ee.wordpress.com/2011/http://aa7ee.wordpress.com/2011/07/24/the-wbr-a-simple-high-performance-regen-receiver-for-40m-by-n1byt/07/24/the-wbr-a-simple-high-performance-regen-receiver-for-40m-by-n1byt/

Yours,

Dave Richards

AA7EE

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics"
http://soldersmoke.com/book.htm
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The Dish

Our man in Dayton, Bob Crane, W8SX, sent us a really beautiful picture of my favorite antenna (not the one above). Check it out: http://apod.nasa.gov/apod/ap110721.html

We talk about "The Dish" from time to time on SolderSmoke. That's the name of the movie about the role of this antenna in the reception of the TV signals for the Apollo 11 moon landing. This is -- without a doubt -- the best movie ever made about an antenna.

You can get the movie at the Gadgeteer Book Store:
http://astore.amazon.com/contracross-20?_encoding=UTF8&node=8

Check out "SolderSmoke -- Global Adventures in Wireless Electronics"
http://soldersmoke.com/book.htm

Steve "Snort Rosin" Smith: Silver-Tongued Devil! Dual-band "Vlad the Inhaler" RX

You'll see in the comments attached to my last blog post that our man on the left coast, Steve Smith, gave that cute little Doug DeMaw/Vlad Polyakov receiver a name that might set American-Russian ham relations back a bit: He called it "Vlad The Inhaler." Good one Steve! (But you might want to stay out of the diplo game!)

It occurred to me that with the installation of one little switch in the diode part of the circuit, we could turn this into a dual-band RX. Take a look here:

http://soldersmoke.blogspot.com/2010/03/polyakov-plus-dual-band-receiver-with.html

Check out "SolderSmoke -- Global Adventures in Wireless Electronics"
http://soldersmoke.com/book.htm

Doug Demaw and Vlad Polyakov

I was looking through W1FB's Design Notebook the other day and I came across the above schematic for a direct conversion receiver (page 111). Note the Polyakov detector. One strange thing though: Doug was running the oscillator at the operating frequency. I thought the big advantage of the Polyakov design was that you ran the oscillator at half the operating frequency (that's why it is sometimes called a "subharmonic" detector). Any ideas on why Doug did it this way?

Check out "SolderSmoke -- Global Adventures in Wireless Electronics"
http://soldersmoke.com/book.htm

Royal Order of the Sputnik Clone Chasers

Kettering Group, UK

From the Chief Designer (AA1TJ):

Fellas,

I came across an online blurb for the recent book, Sputnik: The Shock of the Century, by Paul Dickson; a worthwhile read, judging from the introduction and first chapter.

http://www.sputnikbook.net/intro.php

"Someone brought out a shortwave radio, and soon a beeping noise filled the room. A Russian scientist, Anatoli Blagonravov, confirmed it was Sputnik. "That is the voice," he said dramatically. "I recognize it." John Townsend Jr., one of the scientists at the party, recalled watching Blagonravov: "I knew him quite well, and I could tell that he was a little surprised and quite proud. My reaction was 'Damn!'"

And so an abstraction now had a voice. It also had a name - Sputnik.

Many of those at the party adjourned to the Soviet Embassy's rooftop, attempting to view Sputnik with the naked eye. Several of the American scientists drifted over to the American IGY headquarters in Washington, where they began speculating on what impact the satellite would have. They feared that the American people would be disappointed.

It also dawned on them that they had better start tracking the satellite's orbit. They got in touch with the American Radio Relay League in West Hartford, Connecticut, asking its 70,000 members-all "ham" radio operators-to lend a hand and help track the Sputnik. In less than twenty-four hours, reports on the satellite were coming back to the National Science Foundation, where a temporary control room had been established. Eventually, these hams and other amateur and professional trackers would consider themselves part of a great international fellowship known as ROOSCH, or the Royal Order of Sputnik Chasers."

That's right guys...ROOSCH...the Royal Order of Sputnik Chasers. And to think that fifty four years later a second great international fellowship would rise from the ashes...ROOSCCH, or the Royal Order of Sputnik Clone Chasers! ;o)

(BTW, October 4, 1957 is an important date in American history for a second reason. On that evening the first episode of Leave it to Beaver made its debut.)

...............................................

I thought we should also at this point remember the intrepid lads of the Kettering Group, pictured above. (Some of those dudes look like they would have been right at home in "Leave it to Beaver.") For more info on their amazing Sputnik adventures go here:
http://www.svengrahn.pp.se/trackind/getstart/oldcyts.htm
and here
http://www.svengrahn.pp.se/trackind/trackin1.htm#KEttrack

Check out "SolderSmoke -- Global Adventures in Wireless Electronics"
http://soldersmoke.com/book.htm

Sputnik QSL from the Soviet IGY Committee

I like the reminder of Sputnik's IGY connection. This is from an article by John Foley. W7ETS, in the October 2007 issue of QST. Be sure to read the translation in the caption.

Yesterday Billy and I were at the Smithsonian Air and Space Museum's Dulles Airport center. (We volunteer to take visiting relatives to the airport IF we get to go to the Smithsonian afterwards.) We checked for Sputniks. Nyet. I think they have one on display in the main Air and Space building.

I was thinking that listening to a signal from a spacecraft should be part of the Sputnik event. The packet 2-meter signals from the International Space Station are probably the easiest to receive these days.

Check out "SolderSmoke -- Global Adventures in Wireless Electronics"http://soldersmoke.com/book.htm

Australian Antarctic Antenna Archeology

Macquarie Island

Bill,

I caught half of a report on “The 7:30 Report” on Australia’s public broadcaster ABC TV. Not knowing the full Mawson expedition story, I found this interesting. A conservation group is working to conserve the old halfway point radio repeater mast and whatever other bits have survived on Macquarie Island.

The links are to the transcript and the actual report video.

Story Transcript:

http://www.abc.net.au/7.30/content/2011/s3268909.htm

Vodcast videos. They are about 26MB in size. Theyr’e both the same video. Just two different formats.

http://mpegmedia.abc.net.au/730report/video/podcast/r799754_7027600.m4v

http://mpegmedia.abc.net.au/730report/video/podcast/r799754_7027588.wmv

John Dowdell

Yet to do the test

Sydney Australia

Cutting Edge Spectrum Analyser Video

From Alan, W2AEW. That's some great test gear! We'll have to watch our steps with Alan around -- he can ID us from the moment we hit the PTT! I hate to think what some of my creations would look like on that screen. I'd probably be immediately arrested by the FCC!

"The Early Days of SSTV" by Copthorne MaDonald

The Early Days of Amateur Radio Slow-Scan TV

by Copthorne Macdonald

I got my ham license in 1951 at age 15, and like many hams of that era, the bug hit hard. I worked my way through the University of Kentucky's engineering school, taking 5 years to go through, working nights and weekends out at the transmitter of a local 5 kW AM station. Naturally, I was hamming on the way to and from work in my oil-guzzling 1948 Chrysler. The rig was a 15 watt surplus WWII AM rig that took up most of the leg room under the dash.

One day in 1957 I was in the engineering school's library, thumbing through the Bell System Technical Journal, when I came across an article on some Bell Labs signature transmission experiments using ordinary phone lines. For the first time I realized that picture transmission didn't necessarily mean extremely wide bandwidth. And being the ardent ham I was, I instantly wondered if some sort of practical SSTV system could be worked out for ham radio.

I spent my spare time during the next few months looking into the feasibility of the idea. What sort of display tubes were available? (Ans: P7 phosphor.) How did you get frequency response down to DC if ham rig audio response cut off at 300 Hz? (Ans: Modulate an audio subcarrier.) I kept waiting for the fatal flaw to appear, but I saw none. The idea looked feasible.

I took my paper feasibility study to the head of the EE Department, and asked him if I could design and build such a system as part of an independent problem course. (This would give me a few credits as well as legitimize my use of school facilities for the project.) He agreed, and I ordered surplus CRTs and power transformers and such from surplus houses like Fair Radio Sales in Lima, Ohio. During the next 6 months I designed the unit stage by stage, built a "tank" of a flying-spot scanner in the school's machine shop, and put it all together. I still kept waiting for the fatal flaw to appear, but it never did. The system worked!

What is now the Citizen's Band was at that time the 11 meter ham band. All sorts of strange emissions were allowed on 11 meters then, and the first on-air tests were conducted on that band. Since only one set of SSTV equipment existed, audio tape recordings of the SSTV signal were transmitted on the air by one ham station. At the receiving station we listened to this weird sound coming out of the receiver's loudspeaker as we watched the transmitted pictures being painted in light on the screen of the P7 (long-persistence phosphor, radar-type) cathode ray tube.

I wrote a paper describing the system, and entered it in the American Institute of Electrical Engineers (now IEEE) student paper competition in 1958. It won national first prize that year. The ham community first heard about the system in articles that appeared in the August and September 1958 issues of QST magazine.

Shortly thereafter we hams lost the 11 meter band to CB, and had no long-distance HF frequencies on which to use SSTV. I spent the next 10 years working with hams like Don Miller, W9NTP, and Robert Gervenack, W7FEN in specially authorized on-air tests to convince the FCC that slow-scan would cause no problems to regular ham activities and should be permitted in the 75- to 10-meter voice bands as a regular operating activity. In 1968 the FCC finally authorized SSTV operation on a regular basis in the HF bands. In the 1970s my interests shifted to the USES of ham radio -- to "New Directions Radio" -- ham radio for personal growth and social change. Since 1985, I've been spending most of my time writing -- some of it for rent and food money, some on dear-to-my-heart subjects like the development of wisdom, and strategies for living the most effective life possible.

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

Please Put Drake 2-B Serial Numbers Here!

Let the count begin! Folks have been sending in Drake 2-B serial numbers. They've been coming in via the blog, via e-mail, twitter tweets, Facebook messages, carrier pigeons, etc. I'm afraid I might miss some precious numbers. So let's put them here. If you have some, and I don't have them below, you can post them as a comment to this blog post. When we get enough, we'll turn them over to Scott, K6AUS, for analysis using the same mathematics used to determine the number of German tanks during WWII.

Mine: 11976
Aramand's three (scandalous to have THREE!): 2599, 5149, and 12038
WB4NCT's: 8682
From Rogier's e-bay search: 8069
Another from Rogier: 5153
More from Rogier: 11222, 9041, 9180
From WB4HFN's web site (thanks Rogier!): 2008, 4025, 9289, 11059, 12060
WA5DJJ's: 5254
N5JKY's: 10616
Stephen NM7J / HS0ZHB 12955, 10328
Pete, VE2XPL's: 8873
WA5BDU's: 4950

Armand's 2-B (X3)

Good morning Bill!,

Let me start of by letting you off the hook (a little anyway), by saying that I no longer hold you responsible for the escalating values of the Drake 2B. After acquiring one, cleaning it , recapping and tweaking it, it's pretty clear that the 2B doesn't need anyone to sing its praises. It sings pretty well all on its own! Having said that, I really have to thank you for nudging me into finally getting one for myself. After a lot of searching I finally found one that was in not too bad shape for its age. I also found two others that were in less than working condition. For a while I was troubled as you were about having more than one Solid State Design. Is it really ethical for someone to have more than one 2B? Fortunately I can rationalize with the best of them. It's obvious that I will only own them for a while and am saving them from the scrap heap. Maybe we could start a 2B rescue organization?

Also thanks for the WARC and 160M tuning template - much appreciated!
The serial numbers for these sets are

2599, 5149, and 12038

Will be neat to get an estimate for the final count. Good luck!

Also wanted to mention that I really enjoyed SolderSmoke "the book". Will there be a second volume? Enough for now.

Keep the solder flowing and the podcasts and blogs comming.

Thanks again,

73's

Armand WA1UQO

p.s. If you have an extra set of crystals for a 2B that you would be willing to part with, let me know.