danrae@verizon.net said: > Maybe, but simply by adjusting mine by measuring the 32 kHz output with an > accurate counter I can get them to keep to within about one second a month. What did you adjust? I assume it's software. How well do typical VCO adjustments work with tuning forks? My sample runs about 2 ppm fast but it's stable with 0.2 ppm peak-peak. http://users.megapathdsl.net/~hmurray/time-nuts/Temp-tcxo32khz-a.png danrae@verizon.net said: > I doubt that any of the fancy schemes being proposed for measurement will > improve the basic accuracy much. I assumed the discussion was for the fun of measuring something rather than than trying to make it significantly better. -- These are my opinions. I hate spam.