This woman appears to have a high level of admiration for her lamp. And the admiration is well deserved, since it’s not just a lamp. Instead, it has a four-tube radio receiver in its base, with the loudspeaker at the top. A single plug-in cord provided power to both the radio and the lamp, and the lamp was available in several color combinations.
It was shown 85 years ago this month in the January 1939 issue of Popular Science.
Eighty-five years ago this month, the January 1939 issue of the British magazine Practical Mechanics carried the construction plans for this two-tube shortwave receiver. The exact circuit is a little hard to follow, since the magazine included no schematic diagram. Instead, only the pictorial diagram below is shown. But the left knob served as coarse tuning, with the center knob for fine tuning. The control on the right appears to control regeneration.
Eighty-five years ago, the January 1939 issue of the British magazine Practical Mechanics predicted that, someday, appliances will be equipped with three-prong plugs to avoid the situation shown here. In the meantime, I hope British housewives kept one hand in their pocket while ironing.
Eighty years ago this month, the January 1944 issue of Radio Craft carried this circuit for a receiver to run directly from 32 volts. Specifically, a reader requested a circuit that would “work from a 32-volt lighting system.” The circuit used three tubes, 1T4, 1S5, and 1S4. The filaments were in series with a 550 ohm resistor, and 32 volts was sufficient for the B+.
The “32-volt lighting system” was undoubtedly a Delco Lighting Plant, designed for lighting up the farm. It consisted of a motor generator which charged 16 2-volt batteries. The generator would kick in automatically when the batteries needed charging, and shut off when they were fully charged.
The only mystery here is the reader’s return address, New York City. While some parts of the city had DC power at the time, it was 110 volts. He must have been designing the circuit for someone on the farm without electric service.
I remember this colorful receiver on the cover of Elementary Electronics for January 1974. It was a basic regenerative receiver, and used an audio amplifier module to drive the speaker. But it was more than a radio, it was a circuit for the electronics experimenter to play around with something new, the varactor diode.
As the accompanying construction article noted, even though most radio components had gotten quite small, the tuning capacitor was the limiting factor, since they couldn’t get much smaller. For radios to be as small as they are today, something different was needed, and that ws the varactor diode. When reverse biased, many diodes act as a capacitor, with the capacitance varying with the voltage. Some varactor diodes were on the market, but this circuit allowed you to swap out random diodes and see how they performed. To get the circuit working, you could put a 100 pF capacitor (or maybe a standard 365 pF variable) between J3 and J4, and make sure the set was working. Then, you could try out various diodes and see how they perform.
I also remember the cartoons below, from the same issue. In this case, there was no capacitor to capacit, but the varactor took the honors instead.
Sixty years ago this month, the January 1964 issue of Electronics Illustrated noted that it had been just over six decades since Marconi bridged the Atlantic without wires or ships in 1901. In the intervening years, the job had been done with satellites such as Telstar I and II.
But on July 26, 1963, a new experimental satellite, Syncom, had been launched from Cape Canaveral. The satellite was new in that it was synchronous. Its orbital period was 24 hours, so it seeming hovered at the same longitude. Since it was launched from 33 degrees north, it actually did a figure 8, hovering between 33 north and 33 south. But that was good enough to be continuously visible from both America and Europe and 22,300 miles.
The magazine noted that if such a satellite were launched from the equator, then it would stay above a single point on the earth’s surface. The magazine didn’t use the word, but this is what we know today as a geosynchronous orbit, although most geosynchronous satellites are today launched from other locations, first into a geostationary transfer orbit before being maneuvered into geosynchronous orbit. According to the magazine, the satellite’s two transmitters put out about 2 watts on 1915 MHz.
Happy New Year from OneTubeRadio.com!
It’s that time of year again, when the Big Calendar Companies take part in a conspiracy for you to hand over your hard-earned money to buy a new calendar. But 2024 is a leap year starting on Monday, just like 1940 was. So save your money, and feel free to print out the 1940 calendar shown here, which will work just fine in 2024. This one appeared in the Oregon Almanac for 1940, and it also works just fine outside of Oregon.
Just about any profession can benefit from adopting the latest in technology, as illustrated by this self-explanatory picture in the December 1923 issue of Popular Mechanics.
According to the magazine, this gentleman’s profession, somewhere in Europe, was a mendicant. That’s a word you don’t hear very often today, but it sounds a lot better than “beggar.” He had previously operated as an organ grinder (the article didn’t say whether or not he had a monkey), but constantly having to turn the crank proved too hard. Also, the hand organ was very heavy. Therefore, he invested in the phonograph shown here, which required cranking only occasionally after a few songs. Armed with a satchel full of records, he could share his entertainment and eek out a living much more easily.
Here is a snapshot of which TV stations were on the air 75 years ago. The coasts were where most of the action was, but it was clear that TV would soon blanket the nation, as there were stations on the air in places like Wisconsin, Minnesota, and Texas. This listing appeared in the December 1948 issue of Radio News, and lists the stations on the air as of November 1.
For a snapshot of grocery prices in 1954, this ad for Red & White Food Stores appeared in the Tabor City (NC) Tribune, December 29, 1954.
Sirloin steak for 49 cents a pound sounds like a bargain, but there’s been a lot of inflation in 70 years. According to this online inflation calculator, that works out to about $5.59 per pound in 2023 dollars. You might decide to eat the 33 cent bologna instead, but even that works out to $3.77 per pound.
If you were shopping for dinner in 1954, what would you buy?