"msg" wrote ...
Richard Crowley wrote:
"jack" wrote ...

National Semi still makes a "frequency to voltage" converter chip,
so does Analog.

But here's a link to using a PLL -- from National Semi --
Application Note 210
http://www.national.com/an/AN/AN-210.pdf


Note that publication is 29 years old and I don't think any
of the mentioned ICs are still in production any more.

Since when has that stopped real homebrewers? Ahh, I see a slew of
cross-
posted groups (reading from r.r.a.h)

Don't get me wrong. I am working on a couple of projects
that could use circuits like that, but they are simply not
produciton-worthy anymore. :-(