[time-nuts] Oscilloquartz S.A. BVA 8600 OCXO revisited..
kontakt at corallinks.com
Thu Dec 7 13:35:38 EST 2006
When I lately visited the research facility where I had worked in the
80ies*) I was told that the local timescale is still generated by the two
BVA oscillators I had installed back then. One is free running and the other
one is daily corrected against GPS time-scale. (The place is also
fundamental GPS station of Swiss Federal Topography). I havent't discussed
this further with my colleagues - it was a party and not a meeting on
As luck would have it, I was called a month later for a basement clearing at
Swisscom and found myself unexpectedly in possession of four time
distribution mainframes by Oscilloquartz S.A.! Of course, I immediately set
to open the PLL-module of one to check the type of OCXO - it was a 8600 var
02 serial 743!
One of the units is a 5540 model containing a digital PLL and 3 DMTD phase
comparators. Unsteered, it seems to be running with a daily drift well below
1e-11. I plan to keep this one and sell the other units (1987 model), which
are of analog PLL design but have splitters and amplifiers for 2.048/5 and
10 MHz. All units have double power supplies for AC and DC backup.
I measured a bare 8600 out of one of the latter units against the
beforementioned 5540 output; also compared it with a GPS-disciplined GPSTM
unit by Trimble. Some pics of the equipment and preliminary plots can be
seen at the link **) below.
I will sell - preferrably over eBay. Just email me in case you are
*) Zimmerwald Laser Ranging Station ZIMLAT by AIUB
**) bare BVA http://www.corallinks.com/tmbroker/detail1.asp?id=107
F3 timing unit: http://www.corallinks.com/tmbroker/detail1.asp?id=108
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