Hi Bruce, the 1ns performance per second was mentioned by someone else in the previous threads. When you lock a BVA OCXO to carrier phase, I would still expect the PLL loop time constant to be >>20s, thus the 8E-014 / 2s you mentioned is very likely the performance of the BVA Crystal, not likely the carrier phase real-time system output. For example, our Fury with double oven has an ADEV of a couple of parts per E-012 1s to 20s, but that performance is entirely generated by the OCXO, not the M12+. I would expect the carrier phase to improve things at the point where the BVA starts having a rising ADEV. Maybe around a couple 100s? If for example the phase comparator has 1ps resolution (that's really quite a high resolution) to compare the OCXO and carrier phases (1E-012) then it would take >12s averaging intervals in the PLL just to prevent the measurement errors from affecting the system performance above 8E-014. It's late, and I may just be wrong about all this. bye, Said In a message dated 4/24/2008 17:51:25 Pacific Daylight Time, [EMAIL PROTECTED] writes:
They can be almost 2 orders of magnitude better than you assume for short time intervals. 8E-14 performance from 2 to 20 s with 1E-14 at 1 day has been claimed when carrier phase disciplining a BVA OCXO. **************Need a new ride? Check out the largest site for U.S. used car listings at AOL Autos. (http://autos.aol.com/used?NCID=aolcmp00300000002851) _______________________________________________ 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.
