[evlatests] Rubidium and L350 status

[Keith Morris]

Both L350s had their MIB software reverted and were rebooted and
resynchronized approximately 12:50pm.  We tuned the frequency of the
Rubidium standard such that no drift is apparent on time scales of 100s. 
I logged 1-minute averages of the drift over the past hour, and that hour
of drift data showed a trend of approximately 12ns/day (Rb slowing down
wrt GPS), which is on the order of the Maser drift, which was the goal.

I will continue logging for the next couple hours, before we depart the
site, and report any changes in this trend.  It is possible that the Rb
standard will be stable over hours but show an aging trend over days.  If
that is the case, I will either retune in a day or two, or else discipline
the Rb directly to the GPS.