I only see a page of descriptive text. Was there more? -John
==================== > I have attached a low res scan of Robert J. Carpenter's paper NBS > Technical Note 235, issued April 6, 1964. Its a rubidium standard that > was made for NBS. Its the technical specs on the lamp. I'm sure they > probably do it a little different now, but it should give an idea about > what went into the lamp. > > Brian - KD4FM > > > > Bob Camp wrote: >> Hi >> >> The exact "fill" in the lamp is one of those things the Efratom does not >> like to talk about. Best guess is that there is more than just Rb in >> there. >> >> Bob >> >> -----Original Message----- >> From: [email protected] [mailto:[email protected]] On >> Behalf Of Neville Michie >> Sent: Tuesday, September 29, 2009 12:19 AM >> To: Discussion of precise time and frequency measurement >> Subject: Re: [time-nuts] Can anyone spare an LPRO lamp? >> >> >> The lamp in the LPRO may have a significant difference from the other >> lamps. >> The pictures of lamps on Tom's ? page show that each of them has a >> side arm >> which is most helpful for filling. >> The side arm is left out in the cold so any excess rubidium condenses >> there >> as a reserve supply. The vapour (vapor) pressure of rubidium is then >> determined >> by the temperature of the side arm. >> The LPRO does not seem to have a side arm, at least I did not see one >> when >> I looked at mine, and if it has it does not seem to protrude out of >> the oven. >> I can not guess how they filled it. Remember it is mainly empty, I >> think, although >> it may have an inert gas in it besides the rubidium vapour. With >> the right amount >> of rubidium in the tube the pressure will always be right, the only >> problem is that >> alkali vapours are infamous for diffusing into warm glass, and with >> no backup supply >> of rubidium the vapour pressure will drop and the fire will go out. >> Can anyone tell me what the lamp looks like? Mine seems to be a >> simple glass >> sphere. >> >> cheers, Neville Michie >> >> _______________________________________________ >> 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. _______________________________________________ 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.
