[time-nuts] Time from power lines
Hal Murray
hmurray at megapathdsl.net
Sun Oct 5 21:08:08 UTC 2008
(I forgot what the subject of this thread was, but it's not time-nuts Digest)
> The suggestion of using the mains frequency as a reference is not
> practical. There will be no certainty, even after counting for a week
> that the mains frequency will give you a reliable reference. You said
> it yourself - "the instantaneous frequency of the mains is not always
> spot on".
That doesn't sound quite right. I think there are several parameters, and
some combinations might be interesting.
Here are the ones I can think of:
How stable is the clock you are trying to measure?
How accurately are you trying to measure it?
How long are you willing to wait?
> If you want a cheap and cheerful 50Hz reference in NZ, use the frame
> frequency of TVNZ's TV1 or TV2 transmissions.
Is that exactly 50 Hz? US TV is slightly off 60 Hz.
--
These are my opinions, not necessarily my employer's. I hate spam.
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