Tag Archives: Signal Corps

From Raw Crystal to Crystal Oscillator: Crystals go to War in 1943

Many thanks to SWLing Post contributor, Mark (AE2EA), who shares the following AWA video about crystal production during WWII:

Click here to view on YouTube.

Thank you so much for sharing this, Mark. I posted the original film of this a few years ago, but it appears that the YouTube account has been deleted. I’m grateful the Antique Wireless Association has published this. Thank you for the tip!

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“Crystals Go To War”: A 1943 film about the production of Signal Corps radio crystals

Many thanks to SWLing Post contributor, Charlie (W4MEC), who shares this fascinating film which documents the production and calibration of crystals in 1943. I had no idea of the amount of labor and attention to detail this process required–an absolutely fascinating process:

UPDATE (08/09/2022): the YouTube account associated with this film has been deleted by the owner.

Click here to view this same film now hosted by the Antique Wireless Association.

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US Signal Corps: Horseback mobile


Source: Time Magazine; BETTMANN / CORBIS

Yesterday, I stumbled upon this 1940 photograph of the US Army Signal Corps communicating via radio in the field.

I bet that radio kit weighs almost as much as or more than the typical soldier!

Does anyone know what model of Signal Corps radio that would be?


Richard comments:


The original photo is at the site below.

At the link, https://tinyurl.com/hxp5akx

It’s a Radio Set SCR-203 (Phillip pack saddle mounted). Consisted of:
BC-228 transmitter – Transmitter, 2.1-3.1 MHz, 2 ea VT-25 & VT-50, Part of SCR-203
BC-227 receiver – Receiver, 2.1-3.1 MHz, Part of SCR-203
BC-235 control box – Control box, Part of SCR-203

The unit was powered by various battery packs and a GN-35 hand cranked generator and used a 25 ft whip antenna (Image: W.J. Schweitzer collection)

Thanks so much for identifying the equipment, Richard!

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Want a “new in box” Signal Corps BC-454-B?

BC-454-BMy buddy, Eric (WD8RIF) noticed a rather unique find on eBay this morning: a “new in box” Signal Corps Western Electric BC-454-B receiver. While BC-454-Bs are far from rare, it is certainly a treat to find one with its original box and in mint condition.

I have no plans to bid on this unit–I’m sure the ending bid will be a little too rich for me–but it will be fun to see how high the price climbs. Some day, I hope to acquire a functioning BC-454 of my own. (Santa…are you listening?)

Click here to view on eBay.

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