[time-nuts] No more 60Hz, How do I discipline 120VAC 60Hz from a UPS

Bill Hawkins bill at iaxs.net
Sun Jun 26 16:40:58 UTC 2011


My plan for precision 60 Hz was to use a Caesium standard and
an HP 3320B synthesizer. At about that time, some 200 watt
amplifiers became available on eBay. They were designed for
public buildings to do elevator music or emergency announcements.
Accordingly, they ran on 120 VAC 60 Hz or 28 VDC. 24 VDC was fine
but wouldn't quite deliver 200 watts. I bought two. The
transformers are large, and have 70.7 volt line outputs. Low
voltage boost transformers can get closer to 120 VAC if turning
up the volume won't do it.

Never got around to it, and need to lighten the load on the
basement floor. The Caesium standard has been sold. Please write
to bill at iaxs.net for details. I'm in Minneapolis, MN.

Also have a Liebert 2 KW sine wave UPS that requires 96 VDC.
Bought eight 12V 33 AH batteries for it to keep the time rack
running. Six of them died with shorted cells after 6 years, so
the Liebert is available.

Bill Hawkins

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