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
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?
Kettering Group, UK"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 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. 
Macquarie IslandI 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
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.
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/)
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.
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