Lots of info here: http://www.quartzdyne.com/white-papers.html Em 16/03/2016 20:53, "Daniel Mendes" <dmend...@gmail.com> escreveu:
> Quartzdyne makes pressure and temperature sensors for the oil industry > based on quartz xtals: > > http://www.quartzdyne.com/quartz.html > > Daniel > Em 13/03/2016 01:04, "jimlux" <jim...@earthlink.net> escreveu: > >> On 3/12/16 7:35 AM, Bob Camp wrote: >> >>> Hi >>> >>> The conventional MCXO uses an AT cut crystal rather than an SC. It >>> runs on the fundamental and the third overtone. You can build one >>> with just about any normal fundamental crystal. There are also people >>> doing OCXO’s sort of the same way. Back when the MCXO came out, it >>> was about the only way to get a TCXO that had < 1x10^-8 sort of >>> stability. Now you can get that with a cheap (as in not $5,000 each) >>> commercial IC based TCXO. >>> >>> >>> And heck, if you can tolerate the 1.5W warm up power, you can get ppb >> sorts of accuracy in a OCXO at 250mW. (Vectron EX421) They're a few >> hundred dollars. >> >> The Qtech MCXO is about 100 mW, and somewhat bigger than the EX421 (not >> much bigger) >> >> The vectron MX-503 is in the 50 ppb range at 40 mW (I don't know how it >> does the internal compensation.. maybe it uses some other kind of >> temperature sensor) >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
