Monthly Archives: August 2024

1939 Code Practice Oscillator

1939AugPM3Eighty-five years ago, this gentleman is teaching himself Morse code thanks to a one-tube code oscillator shown in the August 1939 issue of Popular Mechanics.

It used a single 12A7 tube, and for the filament, it used a “curtain burner” line cord to drop the voltage to 12 volts.  The article suggested learning the code by sending from the attached chart, and then having someone else, preferably someone already skilled at the code, to send faster and faster.



ATR Power Inverters, 1954

1954AugRadioElec4We’ve previously featured AC power inverters from American Television & Radio Co., of St. Paul, Minnesota. This ad for their products in the August 1954 issue of Radio-Electronics stresses their usefulness in an emergency situation. In addition, it points out how they can be used to power a tape recorder, allowing the busy businessman to dictate memos right from his car, boat, or plane.



Jeri Sullavan, CBS Radio, 1944

1944AugRadioMirrorEighty years ago this month, the cover of the August 1944 issue of Radio Mirror featured singer Jeri Sullavan, who, according to the magazine, was known by GI’s as the girl with the pin-up voice.

She was born in Jersey City, NJ, but the family moved to Bremerton, WA, when she was in her teens. Her first singing job was at a Bremerton ballroom, which paid $1.50 per evening, but she was discovered in San Francisco when some friends asked her to sing with the Bernie Cummins band, and she sang “I’ll Never Smile Again.” Her start in radio came on WSM in Nashville, and at the time of publication, she was a regular on CBS. She was in demand as a performer at camps and canteens. According to the magazine, she lived alone in an apartment two blocks from the studio with her four dogs.



Press Wireless Transmitter Manufacturing, 1944

1944AugRadioNewsEighty years ago, this New Jersey war worker was doing her part to assemble a 2-1/2 kilowatt transmitter for the U.S. Army Signal Corps. Her factory, Press Wireless, made these large transmitters, which were too large for mass production. Each unit was put together by hand, and the guiding principle was to make them rugged. The photo appeared in the August 1944 issue of Radio News.



Separated at Birth? 1954 Solar Cell

1954AugElecWorldAShe has an uncanny resemblance to Ted Baxter’s girlfriend Georgette, played by actress Georgia Engel.

But it’s actually Margaret Bagley, an employee of Bell Laboratories, and she’s showing off a light-powered transmitter on the cover of the August 1954 issue of Radio Electronics. The FM transmitter is being powered by an electric light bulb thanks to 39 silicon solar cells which had recently been developed by Bell Labs. The two-transistor transmitter circuit is shown below, and it’s being modulated by the RCA turntable, which is presumably running on AC power.

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1954 Two Transistor Regen

1954AugRadioElecSeventy years ago, the August 1954 issue of Radio Electronics showed how to make this two-transistor regenerative receiver. It used two CK722 transistors, one for the detector, and another for one stage of audio amplification. It was said to provide ample volume on stations hundreds of miles away.

The set was billed as a preparedness device, as it made “a reliable receptor for emergency use during a power failure should a sudden air attack occur.” Since it was an emergency receiver, the antenna requirements were flexible. Two separate antenna connections were provided, one for a long antenna, and one for a short antenna. The short antenna could include “the shell of a floor lamp or table lamp, the shell of a telephone box, or to one side of an a.c. outlet. No ground connection is made if any of the above antenna substitutes are used. This precaution is necessary because of the possibility of a short in C1.”

The author noted that there was some variation in transistors, and for that reason, it was a good idea to hook the circuit up breadboard style to test them in operation before final assembly.

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1924 Novelty Crystal Sets

A hundred years ago this month, the August 1924 issue of Science and Invention offered these variations on the crystal set. One was built into a teapot, one into a coconut shell, and one was a ring. They had been demonstrated in Chicago and were found by experts to pull in the stations.



Pelmanism, 1939

PelmanismMost of our readers will recognize the figure shown in this ad from the August 1939 issue of Practical Mechanics as Lord Baden-Powell, the founder of the Scouting movement. But the ad reveals that B-P was also a proponent of Pelmanism, what the ad calls the Science of Success. It was a system of brain training, which was said to develop the mind just as physical training strengthened the body.

The ad invited you to write in for details of the course in Pelmanism. But thanks to the magic of the Internet, you can now download the entire course for free. If you prefer hard copies, reprints are available at Amazon.



Some links on this site are affiliate links, meaning that this site earns a small commission if you make a purchase after using the link.

1924 British Radio Workers

1924AugWirelessWorldA hundred years ago, these British workers (other than the watchful foreman standing at the rear, all women, as far as I can tell) are assembling tuning coils at the works of Igranic Electric Co., Ltd. The photo appeared in the August 1924 issue of Wireless World.



1944 British Wartime Civilian Receivers

1944AugPracWirEighty years ago, the August 1944 issue of Practical Wireless announced the introduction of the bare-bones Wartime Civilian Receiver. With British industry concentrated on wartime needs, civilian radios were getting hard to find. And since the government recognized the need to be able to provide information and entertainment to its subjects, it authorized this design.

Two sets were available. Since domestic longwave broadcasting had been suspended during the war, they tuned only medium wave. The plans were made available to all manufacturers, and the sets were dubbed Utility Radios.  In fact, “Utility” was almost a brand name, since they got that moniker from the government’s earlier venture into clothing, which used the Utility brand name,

The mains-powered set retailed for just over thirteen pounds, with the battery set selling for just under twelve.