Fred McKenzie ) writes:
1. Do quartz watches commonly have an adjustment for regulating them?
2. How can I pick up the signal from the quartz oscillator and count it?

So far I've been unable to pick up a signal with a simple loop. I assume
such a signal is at 32,768 Hz, and that it must be amplified to drive a
counter. The trouble I see, is that one Hz error at this frequency
corresponds to a significant error over time.

Fred

If you aren't coupling the signal properly, you won't get a good reading.
I've seen suggestions of getting the signal off the LCD backplane, which
is accessible and probably would work so long as it derives from the crystal
oscillator.

But what were you using for a frequency counter? Unless there is syncing
to the input signal, there will always be a plus or minus 1 on the least
significant digit, because there's no way of ensuring that the timing
gate in the counter will always fall on the same point of the waveform.

Measuring 10MHz, 1Hz is a small percentage of the total frequency, but
as you go lower in frequency the error becomes more significant. You
can increase the gate time, so you can get the .1Hz reading or even .01Hz
reading, which then makes the least significant digit 1/10th or 1/100th
of what it is previously, and thus making the plus or minus 1 error
less significant at 32KHz. But, increasing the gate time means it
takes more time to do the count, so you have to keep things steady for
longer (and with a noisy signal, the affect of the noise may increase
the count error).

Often when measuring low frequencies, they shift things around and
the counter becomes a period counter. Here the input signal becomes
the gate signal, and it is counting a much higher frequency. That
gives the period of the unknown signal, and all you have to do is
mathematically invert the number on the readout. But I'm not sure
how common the period function is on most frequency counters today,
and it would require modification to turn a counter into a period
meter.

Michael