[time-nuts] GPS Locked and Unlocked Performance Comparison

[John Miles]

> To me, the interesting part is that both the Thunderbolt and the Miller
> designs appear to degrade the performance of the OCXO in locked mode at
> short Tau compared to unlocked. The Z3801 does very well < 300sec, but
> degrades the ADEV at Tau farther out. The Fury does best, never
> worse locked
> than unlocked. The practical difference between the Fury and
> Z3801 at short
> Tau looks to be mostly in the OCXO, the Fury is the one that actually has
> the least degradation of the OCXO performance overall.
>
> Performance at short Tau cannot be better locked than unlocked, so it is
> driven by the OCXO and software, but the fact that two designs (we will
> forgive the Miller design, which looks to be mated to a very good
> OCXO

The interesting thing about the Miller example is that if you click on the
link that goes to his page, the OCXO that he shows is just a simple, cheap
Temex(?) part.  I bought 5 or 6 of these, or something that looks very much
like them, for about $20 each not long ago from a UK seller.  Nothing
special about it.

Tom, was this graph taken with his Isotemp 10.0 MHz OCXO, or the cheaper
one?  What was your reference... one of the masers?

-- john, KE5FX