Andy Wade wrote:

Derek ^ wrote:

The traditional approach assuming the outages were brief, was to use a
cheap oscillator (an astable mutivibrator) running from a back up
battery when the mains feed was down.

Yes, that's why I was careful to say "the biggest problem with using the
mains alone ..."

Cheap clock radios are the only things I've seen that have used crude RC
oscillators to cover mains outages, and their timekeeping is utter crap
- 5 min error in half an hour!

--
Andy


Of course they run fast. That way the alarm will wake you early
enough to reset the clock before you leave for work.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida