[email protected] wrote on 03/02/2010 04:51:15 PM: > From: > > "Bob Camp" <[email protected]> > > To: > > "'Discussion of precise time and frequency measurement'" <time- > [email protected]> > > Date: > > 03/02/2010 04:55 PM > > Subject: > > Re: [time-nuts] Vremya-ch Hydrogen Masers > > Sent by: > > [email protected] > > Hi > > Without doing a lot of digging, I doubt we'll find out just what they did > (or didn't) find and fix. They certainly started with a "from scratch" > design. They may have multiple points of departure from the US approach. > > Then again, it may just be a better brand of coating they spray on the > boards.
It does not take much moisture absorption in printed circuit boards and conformal coats to cause significant variation in electrical delay with variation in humidity, given that the dielectric constant of water is about 80. The solution may be no more complex than use of only low-absorption materials surrounded by hermetic metal enclosures also containing a cloth bag of moisture absorbing chemical granules. Joe > Bob > > -----Original Message----- > From: [email protected] [mailto:[email protected]] On > Behalf Of Magnus Danielson > Sent: Tuesday, March 02, 2010 3:05 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Vremya-ch Hydrogen Masers > > Bob Camp wrote: > > Hi > > > > I hear that the US ones look better than the Russian ones when you have > them > > spinning around on a frozen pond. Nether one does a very good > triple axle > > jump though. At least that's what I read on the internet.... > > > > --------------- > > > > There's always been a *lot* of debate about exactly what the source of > > humidity impact on the US built masers is. It's been talked > about for at > > least 30 years. It's not real surprising if somebody > somewhere has found > the > > answer and fixed it. > > Rather, what did the Russians figure out and fixed? > > Cheers, > Magnus > > _______________________________________________ > 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. _______________________________________________ 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.
