Digital clock 101 question

I am a fiend about clock accuracy - my computers synch up with a time server on startup, and all the clocks in our house are synchronized to the second. And I notice almost immediately when any of this changes.

Last night, I was awake in bed and noticed that the clock by my bed said

4:28 when a downstairs windup clock was bonging 4:30. The windup clock isn't perfectly accurate, but when it slips by a minute, typically once a month, I just reset it and it's acceptable for another 30 days.

When I woke up this morning, I noticed an interesting phenomenon: EVERY electric digital clock in the house (five in all, not counting VCR) was two minutes slow.

So my question: Could this somehow be related to the northeastern US power failure? Our house didn't lose power. But if the local utility was somehow "cycling down" its output as a conservation technique - I have no idea if such a thing is possible of course - could THAT have caused my clocks to all lose two minutes?

No other scenario is possible:

- Virtually every night, I notice if the bedside clock matches the windup clock. It did Wednesday night; it didn't Thursday.

- No one else in the house reset the clocks.

- The oldest digital clock has no battery or memory - cut power to it for a nanosecond, and it resets to 12:00 and starts flashing.

- My watch, the computer clocks, the windup clock, and the two battery-powered clocks in the house, along with the clocks in our cars, all had the same (correct) time, two minutes ahead of the one shown on the digital clocks.

Reply to
dakota7
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"dakota7" wrote ....

Time to call Mulder and Sculley.

My understanding was that they shed loads before letting the frequency slip. If you are not at the exact frequency (and PHASE), you can't interconnect to your regional grid. Hard to believe that any area could slip frequency to that extent. Mr. Dakota7 doesn't reveal where he is, either.

Reply to
Richard Crowley

Imagine putting your finger into a running fan. If you don't insert and remove it at exactly the right moment, bad things happen.

Similarly, power generators on the electric grid of the US & Canada have to be synced EXACTLY or bad things happen.

My sense of it is, you DID lose power.

When clocks switch over from the precise 60Hz power line as a timebase to internal (usually cheap) oscillators, they generally gain or lose time.

Reply to
JeffM

Most likely the chimes on the wind up just went off early? Did you check against an outside source?

Who was it who said "A man with a watch knows the exact time, but a man with two watches is never quite sure"

Reply to
CWatters

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