From: Chris Carlen
User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.0.1) Gecko/20020826
X-Accept-Language: en-us, en
Subject: Better than 2ppm TCXO for <$25?
Date: Mon, 28 Oct 2002 04:38:09 GMT
NNTP-Posting-Date: Sun, 27 Oct 2002 20:38:09 PST
I'm putting the Dallas Semi. DS32KHZN/DIP 32.768 kHz TCXO on my parts
list, as the most likely candidate for the clock that will periodically
prod my future Nixie clocks into flipping digits.
It seems to offer a decent 2ppm accuracy over 0 to 40C, so I'll probably
even get about 1ppm since it will be at room temp all the time.
I'm just wondering if there are any other clocks that might provide
somewhat better accuracy, in the $10-$25 range, let's say.
Let's not go off on tangents like Rubidium standards and stuff like
that. I know all about it. But that is $1000, not $25. My
specifications are clear: <= $25.
I suppose there are approaches using standard crystals, and implementing
the temp compensation myself, but that would require a detailed study
into Xtal oscillators, which I am not prepared to do right now, as well
as probably requiring some very accurate instrumentation that I don't have.
Thus, it seems advisable to select the best off the shelf clock that can
maximize accuracy for the price required.
I also am aware that one could use other methods, like interfacing to a
radio controlled clock, GPS, the internet time RFC, etc. Those things
are very interesting, but I'd like to have a clock on my desk before the
end of the decade. Even with a basic Xtal, that will be a challenge for
my slow-going self.
Good day! (well actually, night.)
Christopher R. Carlen
Suse 7.3 Linux 2.4.10