Retrotechtacular: 1970s Radio

Before YouTube, you had to watch your educational videos on film. In the 1970s, if you studied radio, you might have seen the video from Universal Education and Visual Arts, titled Understanding Electronics Basic Radio Circuitry. The video’s been restored, and it appears on the [CHAP] YouTube channel.

The video starts with a good history lesson that even covers Fessenden, which you rarely hear about. The video is full of old components that you may or may not remember, depending on your age. There’s a classic crystal radio at the start and it quickly moves to active receivers. There’s probably nothing in here you don’t already know. On the other hand, radios work about the same today as they did in the 1970s, unless you count software-defined varieties.

We expect this was produced for the “trade school” market or, maybe, a super advanced high school shop class. There were more in the series, apparently, including ones on vacuum tubes, the transistor, and the principles of television.

We were sad that the credits don’t mention the narrator. He sounded familiar. Maybe Robert Vaughn? Maybe not. A little research indicates the company was a division of Universal Studios, although the Library of Congress says it was actually produced by  Moreland-Latchford Productions in Toronto.

Maybe these videos were the next step in becoming a child radio engineer. If you like old radio videos, this one is even older.

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Retrotechtacular: Wire Splicing The Army Way

For those of us who started experimenting with electricity when we were very young, one of the essential first skills was learning how to twist wires together. It seems like there’s not much to learn, but after a few failed attempts with nothing but your fingers, you learned a few tricks that are probably still with you to this day. It’s not surprising, then, that there’s an official US Army way to twist wires together, as this Signal Corps training film from 1941 shows.

Considering that the Signal Corps had nearly 80 years of experience with wiring battlefield communications at the outbreak of World War II, their methods were pretty solid, as were their materials. The film mainly concerns the splicing together of rolls of type W110-B field wire, used by the Signal Corps to connect command posts to forward positions, observation posts, and the rear echelons. More often than not laid directly upon the ground, the wire had to be tough, waterproof, and conductive enough that field telephone gear would still work over long loop lengths. As such, the steel-reinforced, rubber-and-fabric clad cable was not the easiest stuff to splice. Where we might cringe at the stresses introduced by literally tying a conductor in knots, it was all part of the job for the wire-laying teams that did the job as quickly as possible, often while taking enemy fire.

The film also has a section on splicing a new line into an existing, in-service circuit, using a T-splice and paying careful attention to the topology of the knots used, lest they come undone under stress. It’s fascinating how much thought was put into something as mundane as twisting wires, but given the stakes, we can appreciate the attention to detail.

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