Thursday, April 7, 2022

The Vacuum Tube's Forgotten Rival: The Magnetic Amplifier

The video above shows one application of the principal, but be sure to check out the IEEE article:  

https://spectrum.ieee.org/the-vacuum-tubes-forgotten-rival

5 comments:

  1. Indeed this is really interesting! Another nice application is featured on this (http://sparkbangbuzz.com/mag-audio-amp/mag-audio-amp.htm) page where a magnetic amplifier is suggested as an audio amplifier for a crystal set!
    Andreas DL1AJG

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  2. So for a give core, the AC winding will have a maximum Amp-turns before saturation, the DC control will have Milliamps-kiloturns. Increase the Milliamps and you saturate the core proportionally, blocking the proportion of AC permitted to flow. Neat! The near-rectangular hysteresis of ferrite cores gives near-instant switching - and directional flux retention in the AC winding in the 'switched-off' state,the reason Computers' early magnetic memory sizes were measured in cores. Nowadays that term denotes the number of Pentium processors on a given silicon 'chip.

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  3. This is very interesting and I notice in the spectrum article they say to inhibit AC feedback into the DC part of the circuit to use 2 cores wound in opposite directions...The big question is could this be used to amplify RF??

    de M0TFY

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  4. We used Westinghouse designed MagAmps in control circuitry of for utility scale power plant boilers. Specifically in big pumps with 4160 volt motors, used for boiler circulation. They were extremely rugged and reliable devices. I spent a lifetime in electric power generation where proven technology is essential, and flavor of the month designs never become reality.

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