A hundred years ago, these students at Junior High School 61, Bronx, NY, were on the cutting edge of technology as they tuned into a program. The five-tube set was bought, installed, and operated by the students. The photo appeared in the April 1924 issue of Radio News.
Eighty-five years ago, both daughter and Fido were helping Dad install a lightning arrestor for the family radio antenna. Dad noticed that the spark plug from a Model T Ford could screw directly into a 3/4 inch water pipe fitting. So he added a tee to an outdoor tap, screwed the spark plug into the other end, and attached the antenna.
The magazine noted that the same thing could be done with a section of pipe driven into the ground.
This item appeared in the April 1939 issue of Popular Mechanics.
Eighty years ago this month, the April 1944 issue of Radio Craft carried this circuit for a shortwave receiver said to have “brought in those far-off, hard-to-get stations.” It had been submitted to the magazine by one Jerome N. Seibert of St. Paul, MN. He noted that he used the 27 tube as a rectifier, because that was what he happened to have on hand. The use of a power supply rather than batteries is probably because batteries were hard to come by during the war.
The editors of the magazine suggested swapping the 27 rectifier with the 45 tube used as an audio amplifier. They noted that the 27 would provide more audio, and the 45 would be able to supply more power. Some modifications of the circuit were required.
It appears that the author was this Jerome N. Seibert, who would have been 19 years old when he submitted the circuit to the magazine. His gravestone indicates that he served in the U.S. Army Air Corps in World War II, meaning that he was drafted or enlisted shortly after graduating from high school and sending his circuit to the magazine. He died in 1994.
Eighty-five years ago this month, the March 1939 issue of Radio Retailing asked the question of whether radios of that era were good enough. The accompanying article has an interesting discussion of the state of the art of sets of that era. But the short answer to the question was yes, yes they were.
Seventy-five years ago this month, the March 1949 issue of Radio News included pointers for those interested in getting started in Amateur Radio. In just a few years, it became easier to get started, with the introduction of the Novice license, which required code at only 5 words per minute. But in 1949, to get on the air, you needed to pass the test at 13 WPM. But the magazine gave pointers on how to do it, and reminded readers that hundreds of thousands of hams had managed to do it.
The plans for this handsome two-tube set appeared 80 years ago this month in the March 1944 issue of Radio Craft magazine. The author had a broken midget set with a cracked case, one bad tube, and some loose connections, but he was able to use the parts to make this portable TRF set.
For a cabinet, he found some clear plastic. The result, despite wartime parts shortages, was a radio almost as good as the donor.
A hundred years ago this month, the March 1924 issue of Radio News showed the holy grail of crystal sets: One that would provide the elusive loudspeaker volume without any tube amplification. It didn’t require any electrical power, but as the hand crank indicates, it did require mechanical power.
The device was dubbed the Frenophone, and was invented by S.G. Brown of the company S.G. Brown, Ltd., of England. It worked as follows, referencing the diagram at left:
An ordinary Brown telephone receiver, A, with adjustable magnets, is attached to a metal arm pivoted at B, and weighted at the end with counterbalance C. To the reed D and the receiver are attached the steel needle E to whose end is fastened a small disk F covered on the bottom with cork. This small disk is directly above a perfectly level glass plate G. The glass plate, in turn, is mounted on the shaft of a phonograph motor so that it may be slowly revolved. The disc F, as shown in Fig. 2, is suspended by threads H near the edge of the glass plate G. The two threads terminate at the center of the diaphragm L which is the diaphragm of the loud speaker.
According to the magazine, the instrument required very fine adjustment. But once it was set up, it worked satisfactorily, and frequent adjustment was not necessary. If you want to see one in person, you can do so at this London museum.
Eighty years ago, these gentlemen are disassembling an old radio to salvage the parts within. There was a war going on, and those old parts would provide many useful materials. The March 1944 issue of Popular Mechanics reminded them to unsolder all fixed resistors and capacitors, rather than clipping the leads. It also reminded them to save the coils, sockets, and screws in separate compartments in their junk boxes.
The fashionable headgear shown here from a hundred years ago is being donned by an engineer at WDAP in Chicago. The station had these so that the quality of the station’s transmission could be checked at any time anywhere in the studio. The crystal set was mounted on a pair of headphones, which meant that there was no need to sit down at a standard receiver.
Later that year, the station was purchased by the Chicago Tribune, which changed the call letters to WGN, for World’s Greatest Newspaper.
These images appeared in the March 1924 issue of Popular Mechanics.
Eighty-five years ago, radio repairman Lewis P. Evans of Chicago’s Evans Radio Laboratory brought along a camera on every service call. He would snap a picture of the house, or if he was lucky, a picture of a child, or even the family dog.
He would hold on to the pictures for a few months, and then send them to the woman of the house, with the shop’s address on the back. He reported that a woman can’t resist a picture of her own home or someone in her family. The picture would be saved, or perhaps placed in the family photo album. And when the radio needed service, they would know exactly where to find the shop’s address.
This feature appeared in the February 1939 issue of Radio Retailing. According to this 1936 newspaper advertisement, the shop’s address (presumably the one on the backs of the photos) was 7152 S. Exchange Ave.