Category Archives: Radio history

1939 Mobile Rig

Screen Shot 2019-11-14 at 11.50.46 AMShown here in the November 1939 issue of Radio News is a mobile installation dubbed the “Diplomatic,” which could be used by hams, or also for other mobile applications such as police radio. It is shown here in a 1939 Pontiac, but the same equipment is also shown mounted in a Chevy. The receiver, a Howard 438, is tucked away in the glove compartment, and most of the transmitter is located in the trunk. The dial on the dash is hooked to a stepper relay in the trunk, and is used to turn on the filaments and turn the bandswitch.



BSA – NBC Hook Up, 1939

1939NovBLEighty years ago this month, the November 1939 issue of Boys’ Life shows Boy Scouts lending a hand at NBC radio stations. The images here are taken from network headquarters in New York, as well as WMAL Washington. The magazine shows scouts with Lowell Thomas. And Scout Stan Groner of Troop 248, Bronx, NY, is shown with Charlie McCarthy wearing a scout uniform, although it’s unclear whether McCarthy could pass the Tenderfoot requirements.



FCC Radio Intelligence Division: 1944

1944NovPM1Shown 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.

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1969 Universal Remote

1969NovElemElecThe universal remote control is nothing new, as shown by this photograph from 50 years ago, in the November-December 1969 issue of Elementary Electronics. The accompanying article dealt with some of the finer points of operating a public address system, such as dealing with hum and feedback. Sometimes, the remedy for feedback was just shutting off the offending speaker. This ceiling speaker in a hotel banquet room had a convenient on-off switch, and this hotel maintenance man is shown shutting it off with what those in the industry called a “skyhook.”

Today, remote controls are typically electronic rather than mechanical, but there are some jobs where having a long stick is what you need. For those jobs, having a golf ball retriever or a painter’s pole can quickly save the day, and you can order them from Amazon. They are telescoping for easy storage, and once you get one, you won’t know what you did without it. In addition to being useful for extending your reach, they can be used for applications such as supporting an antenna or being a tent pole.

 



1939 Wired Broadcasting

1939NovRadioRetailing2Eighty years ago this month, the November 1939 issue of of Radio Retailing, carried this description of what it called a “community record player. ” The system was operated from a studio in a New York office building operated by the Wire Broadcasting Corporation of America. The company provided two channels, each free of commercial advertising. One channel provided dance music, with the other carrying concert selections. Broadcasting took place from 11:00 AM until 3:00 AM the next morning. The signal was sent out by leased telephone lines.

The subscribers to the service were apartment buildings, such as the Essex House apartment hotel shown in the picture.

1939 Four Tube TRF

1939NovPSThe young woman shown here is on a weekend jaunt, but that doesn’t stop her from tuning in her favorite radio programs, thanks to the four-tube set described in the November 1939 issue of Popular Science. The set was specially designed for overnight travels, since it nested inside an overnight luggage carrier. The entire piece of luggage could be built according to the plans in the magazine, or it could be made up at the local luggage shop. Both the radio and the baggage were attractively covered in airplane-luggage fabric. When she arrived at her destination, she simply took the radio out of the top of her case, plugged it in, and she was again connected with the world.

The receiver itself was a four-tube TRF design.  A curtain burner cord provided the filament voltage.

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A Vision of Postwar Appliances

1944NovRadioCraftThis wistful look at the possibilities for postwar home appliances appeared in Radio Craft magazine 75 years ago this month, November 1944. The idea had been sent in to the magazine by George Predential of Schenectady, NY, and penned by cartoonist Frank Beaven. One wonders what they would think of modern bread machines, some of which are shown below.

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1944 Two Tube Broadcast Set

1944NovPMShown here is Sgt. Donald L. De Velder of Rochester, NY. He was stationed in Panama, and spent fruitless months trying to find a radio. After finding nothing but the opportunity to spend a fortune on an old beat up piece of tin, he decided to take matters into his own hands and build his own.

Together with Staff Sergeant Emmet Ellis of Nigara Falls, NY, he was able to assemble this two-tube set. It ran off the 110 volt line cord, and a short antenna running down his foot locker allowed him to pull in the local Armed Forces station, as well as other Panamanian stations. The cabinet was made of plywood, and almost all parts were scrounged up from junk heaps. The only expense was for the 32L7 tube, which set the Sergeant back $2, although he was quick to point out that he could have found it for 69 cents back in the States.

The set used two dual tubes. A 12B8 served as RF amplifier and detector. The 32L7 provided audio amplification to drive a PM speaker, with the other half of that tube serving as rectifier. The set was written up in the November 1944 issue of Popular Mechanics.  Sgt  DeVelder died in 2007 at the age of 83.

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1959 Novice Receiver

1959SeptPE21959SeptPE3The young man shown here is doing some code practice in anticipation of getting his novice license, using this receiver described sixty years ago this month in the October, 1959, issue of Popular Electronics . The magazine showed how to construct this simple two-tube receiver designed especially for the novice. It tuned the 80, 40, and 15 meter bands using plug-in coils, and those coils were carefully designed to give maximum bandspread over the CW bands, allowing the new novice to tune in the crowded novice bands.

The set was regenerative, but according to the article, it would give most superhets a run for their money.

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1939 Radio Sound Control Studio Set

1939OctBLEighty years ago this month, the October 1939 issue of Boys’ Life carried this ad for two extremely interesting products from RCA, more specifically, the RCA “Electronics and By-Products Division.”  The first is the RCA Sound Control Studio, which enabled aspiring young radio producers to make their own radio programs at home, with a complete selection of devices to make sound effects.

With the set, they could make train whistles, slamming doors, horses’ hoofs, howling wind, driving rain, and many others. And if they also added the “RCA microphone and radio coupling unit,” the program could be heard on the radio in an adjoining room. The set included a book with drama dialogues with certain sound effects specified. The set sold for a mere $5.95.

The other set, which apparently included the microphone and transmitter, was the RCA Electronics Labs kit. The projects contained therein allowed youngsters to build a real radio receiver, transmitter to talk from another room, realistic telegraph set. The electronics labs started at $7.50.