1973 National Scout Jamboree Arts & Sciences Competition

1973MarBLI remember seeing this notice (or possibly one like it from another source) fifty years ago in the March 1973 issue of Boys’ Life magazine.

As an aspiring scientist and Tenderfoot Scout, I was, of course interested in this opportunity to showcase my scientific knowledge before a national audience. The quadrennial National Scout Jamboree was to take place that year, and I was going. Normally, mere 12-year-old Tenderfoots did not participate in this event, but 1973 was an exception. That year, the Jamboree was being held at two separate locations, in Pennsylvania and Idaho. 1973 was the only year it was split that way. And 1973 also had the distinction of being open to regular troops. Normally, individual scouts sign up and are assigned to a provisional Jamboree troop. But in 1973 the BSA made the good decision, never repeated unfortunately, to open it up to all scouts to attend along with their normal troop and leaders. (Among the other events was the “wide game”, about which I’ve previously written.)

By March of that year, we were already signed up, and this announcement showed another opportunity.  The Jamboree was to host an “Arts and Sciences” competition–a science fair combined with an art exposition.  I don’t even remember the art part of the event, but I did sign up right away for the science fair.  My exhibit was Atomic Energy, and I cobbled together a few interesting objects to put on display on my assigned 2-1/2 by 4 foot table.  I remember borrowing a Geiger counter from the county civil defense department, and I had an illustrated brochure from the Monticello nuclear power plant.  It was set up in a tent somewhere on the Jamboree grounds.  After setting it up, I did visit a couple of times, although there wasn’t a lot of traffic.

I didn’t come home with a blue ribbon, but I did earn a red ribbon.  In retrospect, it was probably a participation trophy, but it’s still a prized possession.  Interestingly, this was before I got my ham license, and I never did run into KJ7BSA, the Jamboree’s special event station.



First Amateur Radio Lunar Echoes: 1953

1953MarQSTShown here, on the cover of the March 1953 issue of QST, are W4AO and W3GKP, carefully aligning the W3GKP antennas in preparation for bouncing their 144 MHz signals off the moon.

The feat had been accomplished by the U.S. military a few years earlier, but it was much more challenging with amateur power levels of 1000 watts. The first echoes came in 1950, but the two hams kept the early results under wraps and continued until a definitive echo was shown, which happened in early 1953, on 144 MHz.

The details of the operation were carried in that issue of QST. That first EME (Earth-Moon-Earth) or “Moonbounce” signal required a great deal of technical expertise, but both technical innovation and collective experience have made the feat much more achievable, with many stations logging more than 100 countries. For an idea of the relatively minimal amount of equipment now needed, see W5RZ’s 2016 article about portable EME from a park, in which he made contacts with Europe by bouncing signals off the moon from an antenna strapped to a charcoal grill.



Uncle Fester: The Early Years

Screenshot 2023-03-07 11.53.17 AMShown here, a hundred years ago today, in the Washington Evening Star, March 9, 1923, is film star Jackie Coogan, talking from WGY radio in Schenectady, NY.  The device shown is the pallophotophone, used for recording sound on film.

Jackie Coogan as Uncle Fester (The Addams Family, 1966).jpg

Uncle Fester. Wikipedia image.

If the actor’s name rings a bell, it’s because he went on to play Uncle Fester in the Addams Family.  Perhaps his trademark image with the lightbulb in his mouth was inspired by the pallophotophone.



1943 “Little Giant” Broadcast Receiver

1943MarPM3The March issue of Popular Mechanics typically carried the plans for a receiver dubbed the “Little Giant,” and despite the war, the March 1943 issue was no exception.  The couple shown above are putting the finishing touches on the set.

Wartime parts shortages were taken into consideration, and the set could be constructed with many parts found in the junk box. For example, the coils were wound on the cardboard forms retrieved from an old flashlight battery.

The circuit was a simple 3-tube TRF set, using a 12K7GT as RF amplifier, 12J7GT detector, and a 70L7GT AF amplifier driving a PM speaker. With a good antenna, the set would pull in stations a thousand miles away, but still had good selectivity for use even in a city with many stations.

1943MarPM4



Power Outage Preparedness: 1953

1953MarPMSeventy years ago, the power was out, but this family was safe and warm thanks to following the helpful pointers in the March 1953 issue of Popular Science. The general advice is the same–you should make some basic preparations for power outages.  We’ve previously covered the subject in general, as well as specific provisions for cold weather.

If you have a gas stove today, you can (in most cases) use the burners on top if you light them with a match.  But today, unless you have a very old oven with a pilot light, the article’s advice about using the oven won’t work–on modern gas stoves, the oven requires electricity to operate.  And unless you have an absolutely ancient gravity furnace, it won’t work without electricity.  But letting the faucets drip is still a good idea.

I wouldn’t improvise some kind of burner on your furnace, and there’s no need for an army-style stove.  Today, there are safe propane and kerosene heaters certified for indoor use, as we previously reviewed.

 



1923 Variable Capacitor

Screenshot 2023-02-24 2.50.19 PMA hundred years ago this month, the March 1923 issue of Popular Mechanics carried this self-explanatory idea for a homemade variable capacitor. A glass test tube serves as the dialectric, and the “rotor” is a brass tube sized to just fit over the tube. The stator is foil lining the inside of the tube.

With the dimensions shown here, the capacitance was said to be about 500 pF, which would prove useful for many radio circuits.



Today’s Quiz

1963MarPE

Today’s quiz is from 60 years ago, the March 1963 issue of Popular Electronics. Can you match up the names with the drawings?

Answers will appear tomorrow.



The Importance of Polarized Plugs

1952Mar2LifeThis picture appeared 70 years ago today in the March 2, 1953, issue of Life magazine.

The gentleman in the center is A.W. Shackleford, the mayor of Lethbridge, Alberta. He is demonstrating the importance of using grounded outlets, or at least polarized plugs. He was speaking into one microphone, addressing 800 Valentine’s Day dancers. A local radio station was covering the event, and being a politician, he grabbed that microphone as well.

Unfortunately, a “difference in grounding systems” between the two systems caused there to be a difference of 50 volts through the two mike stands. Undoubtedly, one or both of the two systems had one lead of the power connection attached directly (or through some resistance, hence there only being 50 volts present) to the chassis. All is well if that’s the neutral lead of the electric wire. But one of the two systems had the hot side of the power lead hooked to the chassis.

A radio announcer (left) and alderman tried to pull His Worship the Mayor away from the mikes, but the current froze him in place, and he was not freed until the power was disconnected. He survived the incident, and went on to win future terms as mayor.



1923 Radio Listings

23Feb1923For a snapshot of what was on the radio a hundred years ago today, here’ the radio page from the February 28, 1923, issue of the Washington Evening Star.  Click on the image for a larger version.

If you ever had an old radio with a switch marked “marine band,” then perhaps you could have heard what was being played on NAA at 8 PM, namely, a concert by the U.S. Marine Band, concluding with the National Anthem, right before the 10:05 PM weather report.

If your set could pull in Philadelphia, then there was a bedtime story at 7:10 PM. If you missed that one, maybe you could get the one from Chicago at 7:50.