[sdiy] Software to log frequency every x seconds?

[Ian Fritz]

At 06:35 PM 10/2/2007, Mike Beauchamp wrote:
>  I'd like to graph the frequency
>drift over time of VCO's to see how accurate they are, etc. I've been
>using just a chromatic tuner program on my downstairs computer, and
>running down and writing down the frequency every hour or so.

Characterizing drift as a function of time is -- IMO -- a waste of time and 
effort.  Drift is due to temperature changes, so you should measure the 
temperature drift directly.  Complete instructions at my website:
http://home.comcast.net/~ijfritz/sy_cir9.htm

Basically, you need a means to vary temperature (a drugstore heating pad 
works well), an IC thermometer mounted on the board and accurate frequency 
and voltage measurements.

Ian