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Old September 16th 09, 03:12 AM posted to rec.radio.shortwave
Mark Zenier Mark Zenier is offline
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First recorded activity by RadioBanter: Jun 2006
Posts: 237
Default Shortwave Time Signals - Where have they gone?

In article ,
Brenda Ann wrote:

You know what? It's strange, in a way, but my personal experience is that
when clocks went from analog to digital, they stopped keeping good time. The
old synchronous motors had more than enough flywheel effect that if the line
frequency DID happen to shift for a moment or two, the clock didn't change
speed with it. Now that everything is running off of a crystal (32.* KHz?)
that is mass produced by the billions and no two are alike, nothing keeps
decent time anymore. Were there ever AC operated digital clocks that simply
got their sync from the line?


Most of the LED clock chips with an alarm used in clock radios, from
20-30 years or so ago, used power line cycles. They had a 50/60Hz
configuration input. National Semi MM537x and Sanyo LM8500 series,
and probably some others.

Mark Zenier
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