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

John Miles jmiles at pop.net
Sun Jun 26 00:40:10 UTC 2011

The C. S. Stong 'Amateur Scientist' anthology included a 110V 60 Hz
telescope-tracking drive generator project that used a reversed filament
transformer.  It was a bleeding-edge design for the time, using a CK722 Wien
bridge oscillator (complete with HP-style pilot lamp AGC) and a couple of
early germanium power transistors.  The author found that he had to rewind
the transformer to cut down on saturation loss, but he was otherwise able to
get it to work OK with the crude solid state technology available at the

The author didn't say as much, but I wonder if transformers sold as
'filament' transformers were designed to saturate intentionally, to limit
the inrush current they would otherwise apply to cold heaters.  I would
expect modern transformers to work better, just because their manufacturers
are more concerned with minimizing losses than they were back in the day.

-- john, KE5FX

> -----Original Message-----
> From: time-nuts-bounces at febo.com [mailto:time-nuts-
> bounces at febo.com] On Behalf Of Neville Michie
> Sent: Saturday, June 25, 2011 5:03 PM
> To: Discussion of precise time and frequency measurement
> Subject: Re: [time-nuts] No more 60Hz, How do I discipline 120VAC 60Hz
> from a UPS
> An interesting question about making a 50/60 hertz source,
> Does a 120 to 12 volt transformer have enough inductance to use as a
> 12 to 120 volt transformer?
> Remember, the inductance is proportional to the square of the no of
> turns, where as voltage is proportional.
> cheers,
> Neville Michie
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to https://www.febo.com/cgi-
> bin/mailman/listinfo/time-nuts
> and follow the instructions there.

More information about the time-nuts mailing list