1937 Disco Ball

1937DecPSWhat we know as the “disco ball” has a long heritage, as shown by this depiction 85 years ago in the December 1937 issue of Popular Science. The magazine featured a number of ideas on what to do with a broken mirror, and assured readers that it needn’t signify seven years of bad luck.

1937DecPS2The magazine noted that one use was to provide spectacular color effects for parties and dances. This was done by focusing colored spotlights on a mirror-covered globe. This was made by cementing small squares of mirror on a large ball or toy globe. This was attached to a spindle which could be spun by hand or with a small geared-down motor.

According to Wikipedia, what is now known as the disco ball dates back to 1917.

If you have a piece of mirror left over after making your disco ball, you can mystify your friends with the magic trick shown below:

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1942 Miniature 2 Tube AC-DC Receiver

1942DecPS1Eighty 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.

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Tube Aging, 1947

1947DecRadioNewsThese 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.



Electronics Numbers Quiz

1962DecPEquizToday’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.



1942 Expedient Chassis

1942DecPracWirThe December 1942 issue of the British Practical Wireless carries this self-explanatory hint sent in to the magazine by one J.M. Firth of Beckenham. He noted that there was a great shortage of aluminum and sheet iron for making chasses for radios. Quite possibly to Mrs. Firth’s chagrin, he found a suitable replacement in the kitchen in the form of a tinplate baking tin. He noted that the pan would take solder easily.



1947 Five-Tube Radio Kit

Screenshot 2022-11-18 12.51.08 PMThere’s a reason why this young woman seems particularly cheerful about pulling in a station on her broadcast radio. It’s because she put the radio together herself from a kit.

The kit is described in the December 1947 issue of Popular Mechanics, and from the description, it sounds like an “All American Five” of the type manufactured by the millions. Curiously, though, the magazine doesn’t mention the source.  If any of our readers can identify the brand of this kid, please let us know.



1922 British Frame Antenna & Variable Capacitor

Screenshot 2022-11-18 10.09.13 AMA hundred years ago, this young British woman was pulling in some signals from her garden at 1276 Leeds Road, Bradford.  She is undoubtedly the daughter of one Mr. C.R. Land, who constructed the set and sent the picture to Practical Wireless, where it appeared in the November 1922 issue.

The issue also showed an interesting method of constructing a variable capacitor, as shown below.  The magazine noted that they could be expensive and difficult to make, but this version was relatively easy to construct at home.  It consisted of two sheets of zinc carefully rolled into tubes and soldered together.  The dielectric consisted of waxed paper.

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Science Fair Ideas: 1937 Electric Motor

OnPaste.20221114-100337If Junior wants to impress the judges at the science fair with attention to detail, skill with hand tools, and a generally spectacular project, then this 1985 project is sure to fit the bill. It’s a small electric motor, capable of providing some motive power to other projects.

The diagram shows old-fashioned dry cells, but modern alkaline D cells will work just as well, especially if you get battery holders to keep them in place.

The November 1937 issue of Popular Science shows the complete blueprints for the motor, but without too many verbose instructions. So as long as Junior can read a set a blueprints, the blue ribbon is pretty much assured.

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Book Review: War Diaries by Volodymyr Gurtovy

My friend Volodymyr “Wlad” Gurtovy, US7IGN, has published a book about his experiences living in Kyiv, Ukraine, in the middle of a war. Wlad, like me, is an attorney, and lived a middle-class existence similar to mine, until Russia invaded eastern Ukraine in 2014. He and his family then relocated to Kyiv, but with Russia’s 2022 invasion, he was once again in the middle of the war. His wife and teen son and daughter evacuated to Poland, where they were able to find an apartment, thanks in part to the generosity of friends in America and elsewhere.

He remained behind, partly because he was prohibited by law from leaving, but mostly because he felt the need to stay behind and defend his native land.

The most compelling part of his book is his account of the mundane details of life in the middle of a war. Wlad lives in a fifth-floor apartment building in the middle of a city of 2.8 million (prewar population). Some days, the supermarkets are open, and some days they are not. The mail continues to go through, but some days, it’s too dangerous to go to the post office to pick it up.  Power, water, and heat are sometimes turned on, but they’re often unavailable. When he needed dental work, he was surprised to find the dental office near his home open, staffed by dental students.  There are even a few accounts of his visits to court on behalf of some pro bono client.  To me, the descriptions of how he navigates this dystopia are fascinating, especially since his life prior to the war wasn’t too different from mine.  Many who follow this blog have an interest in emergency preparedness, and I’m sure they will also find this book compelling.

Of course, since Wlad is a ham, radio is a main character in the story. He gets much of his information from the broadcast radio, and one of his main roles has become that of radio repairman so that others can remain in touch when their radio has problems. He also recounts listening in directly to Russian pilots and both Russian and Ukrainian troops.

As the title suggests, it’s written in chronological format, and you’ll have a hard time putting it down, wondering what’s going to happen the next day.

The book is available at Amazon, as a paperback, hard cover, or Kindle.

If you feel moved to provide additional assistance to Wlad’s family, please see our crowdfunding campaign to help with their needs at GoFundMe or GiveSendGo.

 



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