This simple code practice oscillator appeared 75 years ago this month in the December 1944 issue of Radio Craft. The idea was sent in to the magazine by William McGee of Baltimore, MD, who noted that the idea required fewer parts than most other oscillators. The idea was self-explanatory, as it used “the principle of feedback which all sound men have to combat.” It consisted of a microphone set in front of the speaker of a radio. If the set had a phono jack, it could be connected there. If not, the submitter showed where to wire it into the radio.

No, this is not the scene from a horror movie of giants attacking a radio store. These women are working out a modern store layout, shown on the cover of the December 1944 issue of Radio Service Dealer. With the war still going, radios and appliances were not available. But the end was in sight, and the magazine admonished dealers that it was time to think about how best to display those items when they became available. These women are working out the best display thanks to a demonstration scale model of an average radio-appliance store, commissioned by the Admiral Corporation, 444 N. Lake Shore Drive, Chicago, and realized by George Locks, a “Chicago specialist in miniatures.”

The four by ten foot scale model store represented a store measuring 35 by 90 feet. It came complete with scale models of radios, appliances, fixtures, and furniture.

USS Shaw at Pearl Harbor. Defense Department Photo.

Today marks the 78th anniversary of the Japanese attack on Pearl Harbor, December 7, 1941. Here are links to some of our earlier posts marking that event:

• Broadcasting and Pearl Harbor.
• Pearl Harbor Radio Coverage.
• More Pearl Harbor Audio Clips.
• Keep indoors. Lie down. Turn off the lights. Turn on the radio.
• Remember Pearl Harbor, 1942

Shown above, in front of the Manitoba Legislative Building, are three members of the Women’s Division of the Royal Canadian Air Force. They are Airwomen Elsie Flynn of St. John’s, Newfoundland, Ricky Swedesky of Vancouver, and Dorothy Kidd of Winnipeg. They were all stationed at the No. 8 Repair Depot, Stevenson Field, Manitoba.

Elsie served as a cook in the sergeants’ mess. Ricky was a fabric worker, and repaired the skin covering the airframe of training aircraft. She also packed parachutes. Dorothy was en equipment assistant.

The photo appeared on the cover of the November 1944 issue of Manitoba Calling, the program guide for CKY Winnipeg, pointed out that the Women’s Division slogan was, “they serve that men may fly.” The appearance of women in the air force meant that men were freed up from various ground duties and moved to air training. The magazine pointed out that the Women’s Division included not only girls from every corner of Canada, but also from the United States, Newfoundland, and the West Indies.

Shown at left are Airwomen Olive Carlson of Nanaimo, B.C., Joyce Urie of Windsor, Ont., and “Petie” Houston of Hamilton, Ont. They are at the controls of radiotelephone equipment and tasked with maintaining contact between the ground and Canadian aircraft aloft.

The war plant worker shown here is conducting perfomance tests on a piece of military equipment. She is in a copper-screened booth at RCA laboratory. The picture appeared 75 years ago this month, November 1944, on the cover of Radio News.

This compelling testimonial appeared in Radio News 75 years ago this month. Somewhere in the Pacific, a soldier found a crate washed up on shore, with a National receiver inside. He and his buddies checked it out, cleaned it up, grounded it (probably a good idea), and fired it up. Despite its time spent in the brine, it functioned flawlessly.

The young man shown here is pulling in the short waves thanks to a simple receiver designed around wartime parts shortages. The set used three tubes, which could be types 30, 199, or 201-A, obsolete tubes used by older battery sets. It featured two stages of audio amplification, and could drive either headphones or a small speaker. It pulled in shortwave signals from 160 to 10 meters with homemade plug-in coils. The detector was regenerative, with a variable capacitor controlling regeneration.

If B batteries were unavailable (a likely scenario given wartime shortages), then the transformerless battery eliminator shown here could be used.  The set appeared in Popular Mechanics 75 years ago this month, November 1944.

Shown above, from the November 1944 issue of Popular Mechanics, is one of the operators at an FCC Radio Intelligence Division monitoring stations. He was rotating an antenna capable of narrowing down the incoming signal to one degree, in order to track down a clandestine transmitter somewhere in the U.S., or even abroad.

The majority of operators were hams, and they had the procedure down to a science. They scanned the bands looking for unfamiliar signals. As soon as an unknown station was heard at one station, other stations were immediately notified by teletype and took bearings. Those bearings were then sent to Washington for a fix. At that point, one of 50 mobile units was notified, and would sniff out the transmitter. Finally, an RID man would find the exact location on foot. And as shown below, they would then raid the offending location, presumably with FBI men accompanying with the machine guns.

Before the war, there was little need for such extensive monitoring. But from 1940 to the date of the article, over 9000 cases of unlicensed and subversive transmitters had been spotted. Over 200 spies had been rounded up in South America thanks to RID bearings.

Some transmissions were high speed code, but the stations were equipped with recording devices, and transmissions could be played back at a lower speed. The stations were also invaluable for locating downed aircraft, both military and civilian.