); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] RETRY Hi Bruce:
I've also looked into drilling a hole (garden hose, 90 deg fitting & pipe with end smashed flat to make a nozzle will easily drill as deep as the pipe is long). Then using a short length of capped copper pipe at the bottom and the rest PVC. Like I think here in California wine country 4 feet would be plenty deep. But this method only works at your home location. Not too good for a clock that will be sent to someone else. I think the long time constant method can be done in a few cubic inches. Have Fun, Brooke Clarke http://www.PRC68.com http://www.precisionclock.com http://www.prc68.com/I/WebCam2.shtml 24/7 Sky-Weather-Astronomy Cam Bruce Griffiths wrote: > ); SAEximRunCond expanded to false > Errors-To: [EMAIL PROTECTED] RETRY > > Brooke Clarke wrote: > >>Hi: >> >>Something I've been thinking about is attaching a large thermal mass of >>aluminum to the crystal and it's oscillator then surrounding that with >>insulation. Then surround that with a thin copper layer. Temperature >>sensors >>on the copper and aluminum. If the thermal time constant could be made very >>close to 24 hours, or integer multiples of that, it might be possible to >>predict the inner temperature allowing compensation. >> >>Has this already been done? >> >> > > Brooke > > Why stop there? > Try burying the oscillator under 6ft or so of soil. > The daily temperature fluctuations at this depth are very small. > > Bruce > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
