On 6/27/11 5:09 PM, threeneurons wrote:
A typical crystal has 30 to 50 ppm accuracy, or between 15 to 26 minutes off, in a year. You'll get no improvement with a common crystal. You might just as well just stick with the line sync, and just occasionally hit that minute button, to correct the time.
I use cheap crystals for my clocks and watches. But I get 2 PPM accuracy by adjusting them with a variable capacitor. The capacitor costs 50 cents.
I did have to buy an HP counter, the 5245L Nixie tube model, at surplus for $20 to have a suitable test instrument. Now and then it needs servicing, so I have a parts box on hand whose oven blew out.
I also had to work out the proper settings and offset to adjust the Nixie watch crystal, since it runs at 32768 Hz and is rather sensitive to the capacitance of the scope probe I use to measure the frequency, even when I probe it on the chip side of the 510k ohm drive-reduction resistor.
-- David Forbes, Tucson AZ -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To post to this group, send an email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
