[time-nuts] Source of Rubidium Lamp for Efratom FRK

[Mike Niven]

Would anyone know of a source of the Rubidium bulb fitted in the Efratom FRK (and probably other FRx) standards?  I have repaired and refurbished my Racal 9475, which is fitted with the older style FRK (not -H or -L) module.  It is working properly at present but the lamp voltage is down to 5.5V, which is below the stated minimum of 6V.  I have tried rejuvenating the bulb using a hot air gun, as described by Corby, but this has had no obvious impact.  Hence, I have little feel for how much life the existing lamp has left and a spare would be good for my peace of mind.

Many thanks.

Mike