[sdiy] Software to log frequency every x seconds?

[Mike Beauchamp]

Thanks for the info Ian, definitely bookmarked.

What I wanted to do is measure existing VCO designs to see how stable
they are in typical situations, and to see how long they take to "warm
up" and become stable. So I was hoping there was a program that could
record the frequency every x seconds and just save that for me, then I
could graph it and see how many minutes they take to become stable..
or if they still manage to drift despite a controlled temperature.

This is more of a curiosity rather than any tests I'm running to
attempt to make changes to a design right now.

Mike



On 10/2/07, Ian Fritz <ijfritz at comcast.net> wrote:
> 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
>
>