> So far it seems to have good long term accuracy - maybe a minute
> or two in 6 to 12 months

Is that + or - ? I can imagine how extra pulses would get to the
counter - for example the fridge turning on in one house would
make a terrible pop in the stereo, and this PC will pick up lights
(filament) being turned off in this house, much to my annoyance
if recording audio

A minute-ish out in 6 months is quite a few pulses, perhaps 4,000 in
800,000,000. A small fraction though, ~ 0.0005% or 5ppm. An
average of 1 mains cycle per hour-and-a-bit

> same kind of accuracy as you might expect from the clock on your
> microwave oven etc

I have 2 VCRs with clocks. A much-loved Mitsubishi was a very good
time-keeper. The Panasonic is awful, perhaps 2 minutes fast a month.
The Digitor is a little slow. You'd think mains equipment would take
their timing from the mains, but I'm sure some must use a crystal. Not
having to configure them for 50Hz/60Hz markets (or countries with
sloppy frequency regulation) might be the reason, although they would
need NTSC/PAL/other models so it's not like they go in the box all the
same anyway

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