This woman is providing civilian defense communications as part of the War Emergency Radio Service, using a 112 MHz transmitter-receiver shown in the December 1942 issue of Radio News.
The set was completely self-contained. It’s transmitter section put out a hefty ten watts, and the batteries and dynamotor were built in to the cabinet. Both the transmitter and receiver could tune the entire 112-120 MHz band.
A hundred years ago, Santa was getting ready for Christmas. When it came time to make his list and check it twice, he made sure he got the most current information by radio, as shown in this illustration on the cover of the December 1922 issue of Radio Age.
A hundred years ago today, the December 19, 1922, issue of The Rock Island Argus and Daily Union carried this ad for Franc’s Furniture Store, featuring a complete radio set for only $15, which could be paid just $2 down and $1 per week. It was assembled and guaranteed by the S&M Radio Shop of neighboring Davenport, Iowa.
The set, the “Little Aristocrat,” featured a mahogeny case, and included detector, headphones, antenna wire, and insulator. It was touted as having a range of 100 miles, and would pull in station WOC, which was then licensed to the Palmer School of Chiropractic. The set was billed as an ideal eleventh hour Christmas present.
A hundred years ago, it was going to be a Radio Christmas, as shown by this advertising feature in the Washington Herald, December 18, 1922. Various dealers had completed sets starting for $11, and one of the ads noted that Santa still had plenty of time to set up a radio.
One of the ads mentions the “Literary Digest Hookup,” which is probably the set shown here, which we previously featured. The plans for that set appeared in the April 22, 1922, issue of the magazine, and the girls shown here were later featured for having constructed it without assistance.
The newspaper noted that December 23-30 was to be Radio Week, a time for promoting the new art and putting more sets into American homes.
Sixty years ago, the December 1962 issue of Radio-Electronics showed how to make this converter to listen to TV sound in high fidelity. Of course, one way to do it would be to simply tap into the audio detector of the TV set, and feed that to the hi fi. But that, according to the article, left a lot to be desired, since it usually resulted in buzz, distortion, and background noise that would stand out like a sore thumb in a good audio system.
The solution was to build this converter, and feed it into the FM receiver. And most of the circuit was available off the shelf, in the form of the TV tuner. When these needed repiar, the local repairman typically removed them and traded it in for a rebuilt unit, making the rebuilt units readily available. Ads in the same issue of the magazine showed complete tuners for about $9.95. This tuner had a 44 MHz IF, meaning that the sound IF was 41.25 MHz.
To be able to tune this in on an FM receiver, the builder first tweaked the slugs and trimmers inside the tuner to bring it up to 44 MHz. This was fed into an amplifier-doubler, with the grid tuned to 44 MHz and the plate tuned to 88 MHz. The result was that the output showed up on 88 MHz, at the bottom of the FM dial.
With a reasonably good antenna, the little converter was said to provide good sound reception for stations up to 75 miles away.
Seventy-five years ago today, the December 15, 1947, issue of Life magazine carried this RCA Victor ad showing some of the company’s offerings for the Christmas season.
It featured first the model 63E phonograph, which featured both plenty of volume for dancing, but also fine tone for the more serious music.
The handsome model 68R3 radio tuned in both AM and FM bands, and included the ability to plug in a record player.
Finally, the model 75X11 was only 10 inches long, and the dial face and pointer glowed when the set was on, making tuning of the AM band easy. It also came as model 75X12 in ivory-finish plastic.
Shown here from a hundred years ago is the 7th place winner in the “Simplest Radio Outfit Contest” shown in the December 1922 issue of Science and Invention magazine.
The self-explanatory set was designed by one George Goga, who took home a $25 prize for his entry. The magazine noted that almost all of the parts, with the exception of the headphone, could be found ayt no cost in the home junk box. A pencil forms the chassis. The eraser is removed and a galena crystal inserted in its place. The coil is wound along the pencil, with about 3/16″ of the insulation cleaned off so that the slider can contact the wire.
Mr. Goga reported that he lived several miles from station KDKA, and was able to pull in concerts clearly with a 50 foot long antenna 10 feet high.
Eighty years ago this month, the December 1942 issue of Popular Science showed how to put together this two-tube AC-DC set. The miniature set used two midget tubes, types 9001 and 9002. The 9002 pentode served as a sensitive detector, and the 9001 triode was used as a rectifier.
The filaments were wired in series, and since they required a 600 ohm dropping resistor, not one but two “curtain burner” cords were used, wired in series.
With a short antenna lying along the floor, the set could pull in local stations with good selectivity. Out in the country with a 75 foot antenna, it boasted a range of 600 miles.
These workers at Hytron‘s plant in Newburyport, Mass., are aging tubes to ensure long life. An incandescent lamp is wired in series with each tube element to limit current. This process of seasoning and degasifying the tubes ensures more uniform tubes.
The photo appeared on the cover of Radio News, December 1947.
Today’s quiz comes from the December 1962 issue of Popular Electronics. You have to match up the number associated with each diagram. Answers will appear here tomorrow.