1939 One Tube Loudspeaker Receiver

Screenshot 2024-09-05 12.52.18 PMEighty-five years ago, this young man is making the final tuning adjustments for the one-tube radio he built from plans in the October 1939 issue of Popular Mechanics.

The set was simplicity itself, but it boasted a loudspeaker and AC power, so there was no need to mess around with headphones or a B battery. It was really a crystal set, with a fixed crystal detector. The single tube was a 25A7GT, which combined a pentode AF amplifier with a rectifier. Of course, it had a hot chassis and the familiar “curtain burner” cord to power the filaments.

It was best suited to tune permanently to the same local station. It wouldn’t tune the entire broadcast band without changing the fixed capacitor in parallel with the tuning capacitor, and tuning was very broad. But if you wanted to listen to a local station with loudspeaker volume, the simple design couldn’t be beat.

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Happy Birthday, President Carter

CarterToday is the 100th birthday of the 39th President of the United States, Jimmy Carter, the first former president to become a centenarian.

I never voted for Jimmy Carter.  In 1976, I was too young to vote, and if I had been able to vote, I would have voted for Ford.  And in 1980, I proudly cast my vote for Ronald Reagan, and would do so again.

But we have long admired President Carter.  He is clearly a patriot and loves his country.  He was appointed in 1943 to the Naval Academy, making him a veteran of the Second World War and the Korean War.  He went on to serve honorably.  He was undoubtedly the most intelligent person to ever serve as president, his credentials including that of a nuclear engineer.

In addition to being the oldest living former president, he is also the oldest living former governor.  He achieved that position upon the death of former Minnesota Governor Al Quie (another statesman we admire) in 2023.

Happy Birthday, Mr. President.



1939 Three Tube Receiver

1939SepRadioCraftEighty-five years ago this month, the September 1939 issue of Radio Craft carried the plans for this receiver, which the magazine dubbed the tiniest ham receiver.

The three-tube (including rectifier) set had a regenerative detector and one stage of audio amplification to drive a set of headphones. It tuned 9.5 through 700 meters with a set of six coils, meaning that it tuned the entire shortwave spectrum, the broadcast band, and could even pull in SOS calls on 600 meters (500 kHz).

As with many of these designs, it featured a hot chassis, so care must be taken before plugging it in to the power socket.

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1924 Underground Antenna

1939SepAmazingStoriesA hundred years ago this month, the September 1924 issue of Amazing Stories carried this ad for an amazing product, namely this underground antenna from the Curtan Mfg. Co., 154 E. Erie Street, Chicago, the Ground Antenna promised loud and clear reception, regardless of static conditions. You would get better long-distance reception, freedom from static, far greater selectivity, and marvelously clear and sweet tone.

NatlRepBy writing to the company, you would get more details of their risk-free trial offer. It seems like a safe bet. If you decided it wasn’t living up to the promises, you probabaly had to go outside and dig it up to get your money back. This was probably safer for the company than its earlier endeavor, shown in the 1927 ad shown here from National Republic magazine. That miraculous product promised 120 miles on a gallon of gas, as well as instant starts in zero degree weather.



1939 Portable Ten-Meter Station

1939SepQSTShown here, on the cover of QST for September 1939, is the portable/mobile ten-meter station of Harold Bowen, W1DQ. According to the magazine, at the microphone is his unnamed assistant operator.

The details of his station aren’t given, but since the unit on the right has a dial, it’s undoubtedly the receiver, with the transmitter being in the middle.  The unit on the left is unmistakably a dynamotor power supply.

According to this family history, Bowen was a World War 1 veteran, having been in charge of communications on the U.S.S. DuPont.  He died in 1973, according to this obituary.



1939 British One Tube Receiver

1939SepPracMechWhen the September 1939 issue of Practical Mechanics was on the newsstands, Britain was already at war. But if someone needed a radio, this simple design was perfect for wartime austerity. The only manufactured components needed were the tube, one variable capacitor, one fixed capacitor, one resistor, and the headphones.

The coil was homemade, and regeneration, or “reaction” as the British liked to call it, was courtesy of a moving tickler coil, which could be moved in and out of line with the main coils. For mediumwave reception, the top half of the coil was used. To pull in the longwaves, the bottom half was added in by unhooking the clip shoring out the lower coil. Of course, by the time the magazine came out, the domestic longwave service of the BBC was off the air for the duration, although the set probably could have picked up programs from the Continent.

The article doesn’t specify what tube is used, although probably just about any triode would work just fine. It called for 60 volts of B+, although the article noted that there would be an increase in signal strength with 70-80 volts.

The “S.S.” in the name stands for the “simplest of the simple.”

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2 October 2024 Solar Eclipse

NYEclipseThe next solar eclipse is coming soon! On October 2, 2024, an annular eclipse will cross the Pacific Ocean, Easter Island, Chile, and Argentina. We won’t be able to make it to the path of annularity, but our official headquarters for the event will be in Hawaii.

In Hawaii and much of the Pacific, the eclipse will be “just” a partial eclipse. While interesting, it’s hardly worth traveling for a partial eclipse. But there’s an exception, and that is if the eclipse occurs at sunrise (or sunset). And in Hawaii, the eclipse will take place at sunrise. Instead of a normal sunrise, it will be a crescent sun that rises over Hawaii, and we’ll be there to see it. You can read more about the phenomenon at our sister site, SunriseEclipse.com, and, of course, there’s still time to get eclipse glasses from MyEclipseGlasses.com.

The picture shown above, without any special lenses or filters, was taken of the sunrise eclipse of June 10, 2021. That’s the view we’ll have in Hawaii (but without the Statue of Liberty).  We were rained out for the 2021 sunrise eclipse over Lake Superior, but we’ll be making up for it in Hawaii.

Sunrise eclipse. Be there. Aloha.

Photo credit: Wikimedia Commons photo by Anthony Quintano from Mount Laurel, United States – Statue of Liberty Annular Solar Eclipse, CC BY 2.0.



June Travis, NBC Radio, 1939

1939Sep22RadioGuideEighty-five years ago, the cover of the September 22, 1939 issue of Radio Guide showed actress June Travis and her primate friend listening to a favorite program on their portable radio.  Travis was heard on NBC radio in the series “Affairs of Anthony” and “Waterloo Junction.”

The magazine carried a guide to the then-available portables, which noted that these sets had swept listeners off their feet.



Mrs. Jones’ Wartime Chipped Teacup

1944SepRadioCraftTeacupAdDuring World War II, according to this ad in the September 1944 issue of Radio Craft, one Mrs. Jones proudly used this chipped teacup to serve her guest, no matter the guest. She was proud of it because it showed that she was doing her patriotic duty to keep prices under control. She didn’t know the complicated economic theories about inflation, but she knew that she could do her part to stop it by giving up unnecessary spending for the duration. She saved the money instead, and bought war bonds, and after the war, she could buy a lot of things that weren’t currently available.

She also knew to pay no more than ceiling prices, and to follow ration regulations scrupulously.

The ad was sponsored by the War Advertising Council, now known as the Ad Council. It was approved by the Office of War Information.



1928 Grocery Prices

1928Sept20WashStarFor a look at grocery prices in 1928, this A&P ad appeared in the Washington Evening Star, September 20, 1928. Even considering inflation (according to this online inflation calculator,
one dollar in 1928 was the equivalent of $31.77 in 2024) some of the prices look reasonable. For example, 12 pounds of flour would only set you back 47 cents, the equivalent of about $1.20 per pound in today’s money. And grapes were only about 8 cents a pound, or about $2.40 in today’s money.

But eggs were 47 cents per dozen, or almost $15 in 2024 dollars. What would you make for dinner in 1928?