Hal Murray wrote: >> The thing is watches rates are dependent on how you personally wear >> them. Some people's wrists are warmer than others, some people take >> the watch off at certain times of day, others don't... If you wear >> the watch normally, and measure your personal offset, you can adjust >> the crystal to compensate for that change. The watch won't be any >> more accurate at any given instant, but it will stay spot-on over the >> course of a week. > > What's the ballpark for a personal offset?
I am more of a mechanical watch guy, and there it depends on the quality of the watch. Usually less than a couple of minutes per day. After regulating for personal error, I typically can keep to within a minute per week on a good watch. The same is true for quartz. I have had some watches that were nearly perfect on, or off the wrist, and others that lost many seconds per day. >> If you don't have a reciprocal counter, such as a 5370B, you can also >> use a good fractional /N synthesizer, such as the 3666[a,b,c] and an >> oscilloscope. Put the 3666 on the horizontal axis, and the coil on the >> vertical axis. Adjust the synthesizer until you get a good stable >> circle. > > Would it be easier to see any drift if the phase was set to make a line > rather than a circle? Personally, I prefer to connect the synthesizer to the trigger, and set the timebase for 1 cycle of 32KHz, and watch the waveform slip. > > A small shift in a circle just makes a not-round circle. A small shift on a > line makes a slight opening. > > Or is the drift so huge that this question isn't interesting. (just wait a > bit and the picture will change) You are watching cycles slip by, so it moves pretty quickly. -Chuck Harris _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
