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THE AM BULLETIN BOARD => Technical Forum => Topic started by: John K5PRO on October 15, 2015, 03:13:38 PM



Title: Spellman HV power supplies circa 1960
Post by: John K5PRO on October 15, 2015, 03:13:38 PM
This was in the 1960 Radio Electronic Master catalog. Spellman is still a reputable maker of high voltage power supplies, and they still use high frequency inverters with transformers and rectifiers. Glassman and others also make similar units. Imagine then, gettin 90 kV out of a lightweight unit, no oil filled tank with three phase AC primary.

At the now-closed Black Hole junkyard in Los Alamos, I saw a stack of HV power supplies from the 1940s, up to 30 kV, in wrinkle finish and all. Beautifully built, they were tube oscillators with RF transformer, similar to these. They were engraved LASL Electronics Group
Model xx Power Supply

The one I bought eventually crapped out, maybe just needs a tube. It made a nice hi pot tester with meter and all. I should have bought them all, museum pieces.



Title: Re: Spellman HV power supplies circa 1960
Post by: W7TFO on October 15, 2015, 04:06:42 PM
Interesting similarity of the HV RF coils shown to the usual Tesla coil...

73DG


Title: Re: Spellman HV power supplies circa 1960
Post by: Opcom on October 15, 2015, 11:22:39 PM
Those are slick. I have a few supplies from the BH, none of the RF type. Two are large rack mount units of the rectifier-and-oil-cap type. One has four Eimac rectifiers. Very nice. not sure the brands on them.
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