[time-nuts] WTS: Efratom PTB-100 Precision Timebase

[Gregory Beat]

At the 38th Annual Symposium on Frequency Control (1984), a presentation was given on the “Lifetime and Reliability of Rubidium Discharge Lamps for Use in Atomic Frequency Standards” by Aerospace Corp., Efraton-Ball, and EG&G.
https://ieeexplore.ieee.org/document/1537723/

The spattering of Rubidium on the lamp’s inside glass is discussed.

greg, w9gb
Sent from iPad Air

> On Jul 7, 2018, at 5:30 PM, Gregory Beat <w9gb at icloud.com> wrote:
> 
> In 2008, G Molenkamp, VK3UM noted that of the 20 Efratom model FRS-C units he restored, component failure due to long heat exposure caused most of the failures. 
> http://www.vk3um.com/Rubidium%20rejuvination.pdf
> He notes that some lamps had Rb splattered over the inside wall of the glass.  
> In these cases, the Rb material was not consolidated in the “pinch of the glass lamp”.
> Using the “heat gun process” he was able to rejuvenate those Rb lamps.
> 
> w9gb
> ==
> >Time-Nuts Group,
> >For someone interested in working on the Rb package which I believe is the
> >FRK series. Worked great in my lab for years and recently started being real
> >slow to lock during power cycles and now won't lock at all. Not sure what
> >the fair asking price would be in this condition. Maybe someone has
> >repair/refurb experience with the Efratom FRK.
> >Contact me if interested.
> >Don
>