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AVR Power Supply

DonH56

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beefkabob

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It's cool. What is the value, though? How many devices are 3 phase but have such low power demands? The only thing I'd want to run that's 3 phase is a motor for woodworking or the like.
 
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DonH56

DonH56

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It's cool. What is the value, though? How many devices are 3 phase but have such low power demands? The only thing I'd want to run that's 3 phase is a motor for woodworking or the like.

Three-phase power is sometimes used for instrumentation and some gear to reduce noise. I suspect many users will use it as a low-ripple DC source (after rectifying the output). But I wasn't thinking of any particular practical application, just thought it was a neat idea. Every now and then I accumulate knowledge just for the sake of knowledge, I can certainly skip sharing it here.
 
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DonH56

DonH56

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That's very cool. Wasn't there stories of Crown amps being used as variable power sources years ago?

Indeed there were, and for "real" applications, not just arc welding soft steel at audio shows.
 

restorer-john

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I'm pretty sure the AV receiver won't last long driving the low impedance secondaries. The output stage would definitely need flyback diodes to prevent device destruction IMO.

I did a similar thing years back to drive an US made belt drive turntable using an old integrated amplifier, a PA line transformer and a variable frequency oscillator (wein bridge derived) to give me 110V/60Hz for a synchronous motor over here. (we are 240/50Hz).

Cool post Don. :)
 

restorer-john

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Wasn't there stories of Crown amps being used as variable power sources years ago?

Didn't they use them for shaker table actuators or something? Transducers for industrial applications etc.
 

RayDunzl

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Industrial

https://www.aetechron.com/pdf/service/7520.pdf

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beefkabob

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Three-phase power is sometimes used for instrumentation and some gear to reduce noise. I suspect many users will use it as a low-ripple DC source (after rectifying the output). But I wasn't thinking of any particular practical application, just thought it was a neat idea. Every now and then I accumulate knowledge just for the sake of knowledge, I can certainly skip sharing it here.
I wasn't attacking you. Just wondering the usefulness of it.
 

LTig

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That's very cool. Wasn't there stories of Crown amps being used as variable power sources years ago?
In the 80's and 90's NAD2200 power amps were used to drive room temperature gradient coils in superconducting magnets of NMR microimaging instruments. They were modified for better DC stability though.
 
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