Monthly Archives: July 2023

1938 Dining Table Radio

1938JulPSEighty-five years ago, the July 1938 issue of Popular Science showed how to make this handsome radio to proudly put in the middle of your dining room table. The five-tube (really four tubes plus a ballast) TRF was said to be a good performer. The sides were decorated with mirrors, and it also had two flower holders. They were made of plywood, with a cut down tobacco tin inside to allow you to water the flowers.

Apparently, combination radio-flower pots are no longer a thing. The one at the left certainly looks pleasing, but it’s not really a radio. Apparently, the closest you can get today is the combination flower pot-bluetooth speaker shown below. In addition to using it as a normal bluetooth speaker, you can set it to make piano sounds whenever you touch the flower.

1938JulPS2



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1923 Distance Learning

1923JulPSDistance learning is nothing new, as shown by these New York high school students 100 years ago, pictured in the July 1923 issue of Popular Science. While the magazine identifies the school as “Haarken High School” in New York, this is almost certainly a typo, and it should read Haaren High School, as confirmed by this site and others reporting the same accomplishment.

This is the accountancy class at Haaren, and the students are listening to a series of accountancy problems broadcast by WJZ in Newark, NJ (now WABC New York). A receiver and loudspeaker had been installed, and the students are seated at their adding machines. Problems were read slowly and distinctly, and the correct answers were read a few minutes later. “The general correctness of the classroom work was testimony of the clearness with which radio waves carried.”

Witnessing the successful demonstration are officials of the city Board of Education, as well as more than 25 principals of city high schools.



1948 Safety Radio

1948JulPMSeventy-five years ago, this young man was safe listening to the radio unattended, thanks to the “safety radio”. As we’ve reported previously, most radios of that era had a “hot chassis“. One side of the line cord was connected to the metal chassis. The connection did go through a capacitor, but those were known to short out. Depending on which way the cord was plugged in, the result could be a 120 volt shock if you touched any metal on the radio and a grounded object. In this safety radio, the set was safely housed in a one-piece plastic cabinet. The description notes that there is ample provision for required cooling, and there was a handle for convenient portability.

I would be curious to know whether there are any screws on the bottom. And if one of the knobs fall off, the volume and tuning controls are probably made of metal and attached directly to the chassis. The magazine, July 1948 Popular Mechanics, doesn’t name the manufacturer or the model. Maybe one of our readers could identify it.



Movie Review: Sound of Freedom

SoundOfFreedom

Image, Angel Studios.

My wife and I just got back from seeing “The Sound of Freedom,” a thriller originally produced in 2018 but shelved by Disney. It was eventually picked up by independent Angel Studios, and is now in theaters.

It’s a movie about human trafficking. It follows the true story of two children kidnapped in Honduras and whisked away to Colombia. The younger brother was rescued by law enforcement in the United States, and the agent involved took it upon himself to rescue the older sister, still in Colombia. I’m sure this true story is embellished somewhat for the silver screen. But given the societal decay we are currently witnessing, it is very plausible. It’s a story where the good guys win.  And it should be noted that the good guys include Colombian law enforcement and military.

Variety’s review of the movie dismisses the veracity of the story as “insane nonsense.”  Nonetheless, the reviewer goes on to say, “let’s assume that, like me, you’re not a right-wing fundamentalist conspiracy theorist looking for a dark, faith-based suspense film….  You needn’t hold extreme beliefs to experience ‘Sound of Freedom’ as a compelling movie that shines an authentic light on one of the crucial criminal horrors of our time, one that Hollywood has mostly shied away from.”

I agree that the movie is worth seeing.  It’s an exciting thriller, and it carries a powerful message that I need to research further.  And it’s worth seeing now.   It was shelved by a major studio, and it doesn’t have the financial backing of the Hollywood Industrial Complex.  If it’s going to be successful, and it’s deserving of success, then it needs to make its mark at the box office now.

You can buy tickets online at angel.com/freedom.  Eventually, I’m sure it will be available for streaming, but I think it’s important to show that a movie like this can do well at the box office in first-run theaters.  There are a lot of crappy movies these days, and the way to make Hollywood change its tune is to show support for well made entertaining movies with an important message.

Tickets in most theaters run about $12 per person, and we realize that for some people, that cost is simply prohibitive.  If you can’t afford it (or if you’re not sure it’s worth it), then millions of free tickets are available.  The movie is being promoted on a “pay it forward” basis.  Many people (including me) saw the movie for free because someone who had already seen it gave them a ticket.  They are then encouraged to buy tickets for someone else.  So if you’re not sure it’s worth it, the same link, (angel.com/freedom) allows you to get your tickets at absolutely no cost or obligation.  If you like the movie, and if you are able, then you can buy a ticket for some stranger, just like some stranger bought a ticket for you.  When you get to that site, you can click on either “Buy Tickets” or “Claim Free Ticket.”  After seeing the movie, if you wish, you can return to that site and buy tickets for someone else by clicking “Pay It Forward.”

If you are on the fence, here is the official trailer for the movie:

Image, Angel Studios.

Image, Angel Studios.

If you’re a right-wing conspiracy buff, then you’ll definitely like the movie. But even if, like the Variety reviewer, you’re don’t fit in that category, you will still find it a compelling film.  And if you’re like me, you’ll want to educate yourself on the problem of human trafficking.  The movie’s tag line (and the name of one of the Spanish-language songs in the soundtrack) is “God’s children are not for sale.”  Let’s make it so.

Rotten Tomatoes gives the film a tomatometer rating of 88%, with an audience rating of 100%.  The movie is rated PG-13, mostly for the violence (although not gratuitous violence), sexual content, and “smoking throughout.”  Most of our readers will chuckle at the capabilities of GPS tracking devices shown in the movie.  But they’ll nod in agreement at the capabilities of the VHF handheld radios used by both the good guys and the bad guys.

 

 



1948 One Tube Portable

1948JulPracWir1948JulPracWirFrontPicThe plans for this nondescript by effective one-tube portable radio appeared in Practical Wireless, July 1948. The set uses a 6K7 pentode, and uses a singl 4.5 volt battery as its power source. According to the author, F.G. Rayer, G3OGR, the set would pull in local stations with just a short piece of wire. With a longer outdoor antenna, it could pull in foreign stations, although lack of selectivity limited its usefulness. The power switch and band switching was accomplished with three terminals on the front of the radio. For longwave reception, terminals 2 and 3 were shorted out. For mediumwave reception, all three terminals were shorted, effectively shortening the coil. For mediumwave reception only, another coil could be substituted.

According to the author, “it should be unnecessary to point but that the receiver is intended mainly as a novelty, but that even so it is capable of surprising results under certain conditions.”

1948JulPracWirSchematic



1943 British Homemade Alarm Clock

1943JulPracMechWar meant shortages of many things in Britain, and one of those things was alarm clocks. But people had to get up, and the July 1943 issue of Practical Mechanics carried these plans for taking matters into your own hands. It was sent in to the magazine by one R.W. Lewthwaite of Plymouth.

It’s not a new idea. We’ve previously shown similar designs from 1911 and 1921.  The basic idea is quite simple. Since the metallic hour hand is going around anyway, you can set it to make electrical contact at a certain hour and turn on a bell or buzzer. In this case, it turns on both a lamp and buzzer, powered by two flashlight batteries. A switch is also included to turn it off when not in use.

Here, a thin brass extension is soldered to the hand so that it can make contact with a bolt mounted in the glass face. The article even includes instructions for the delicate process of drilling through the glass. The thin brass strap has sufficient slack so that it doesn’t slow down the clock. If that turns out to be a problem, then a thinner piece of brass should be used.

According to Mr. Lewthwaite’s letter to the magazine, there has been a lot of discussion lately about the short supply of alarm clocks. But fortunately, he was able to find an adequate supply of “eight-day car clocks” to press into service.  Presumably, lack of fuel meant that the market for automotive accessories had dried up.

As we noted in our earlier posts of similar ideas, young STEM enthusiasts can use a similar idea to make their own alarm clock.



Keep Your Radio Working: 1943

1943JulRadioRetailingEighty years ago, domestic radio production had been shut down for over a year, and there would be no new radios for the duration of the war. Therefore, it was every American’s patriotic duty to keep their current radio in working order.

In this ad in the June 1943 issue of Radio Retailing, the makers of Tung-Sol tubes was making available to dealers this display of booklets, containing hints for consumers on how to keep their radio working. The ad noted that many Tung-Sol tubes were available to dealers, so that if repairs were needed, they were probably possible.