General thread of obscure old tech

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metasonix
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Re: General thread of obscure old tech

Post by metasonix » Fri Jun 26, 2020 6:27 pm

jesus it's 104 degrees outside.....
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Re: General thread of obscure old tech

Post by metasonix » Tue Jun 30, 2020 5:57 pm

Circa 1932, DeForest put out one of the first power oscillator tubes intended for UHF use: the 525. It appeared on one sales list and vanished -- when DeForest went under. So now the 525 is not Googleable. Sylvania took over their factory and workers, and put out a better version, the 825. Beautifully made, a total sales disaster, and extremely rare today. Too early.

"Now the one question remains, what was the 525 and 825 used in? "

"They weren’t used in anything. deForest went bankrupt before they could promote the 525. After Sylvania picked up many of the folks from the deForest organization, Sylvania marketed the 825 towards the amateur market. However, there is no known factory radio it was designed for.

"This list is a good example of new knowledge adding to old and needing to reread and revisit references, As it appeared on the list, I had no idea what the 525 represented when I first saw it so long ago. Even after I learned of the 825, it still did not “click”. It was only after I figured out that the Sylvania Clifton plant was born partly from deForest engineers coming out of the deForest bankruptcy that it all fell together. From that same list, the deforest 520B and 520M became the Sylvania 820B and 820M."
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Re: General thread of obscure old tech

Post by metasonix » Thu Jul 02, 2020 1:50 am

In 1933, $10 was a LOT of money. Roughly equivalent to $200 today.
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