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Re: 220v/50hz power rig
--On Thursday, 06 September, 2001 10:47 AM -0700 Sean Donelan <firstname.lastname@example.org> wrote:
Actually, its not being clever, its being cheap.
Some do both (or their spec sheets lie). I was about to recommend a unit to Randy, until I downloaded the PDF and thought 'how the hell do you set the frequency'. Further investigation revealed something very like: Input frequency: 47Hz-53Hz, or 57Hz-63Hz Output frequency: 50Hz +/- 0.1%, 60Hz +/- 0.1%, autosensing I guess that has a crystal with two dividers, a PLL, and no obvious way to turn the autosense off. Most units have some reasonably accurate oscillator or it makes regenerating the output hard when there is no input to sync to :-) Some good ones have a PLL to minimize cutover disruption if you take the electronics out of band. -- Alex Bligh Personal Capacity