[time-nuts] LPRO-GPSDO

[Tom Van Baak]

Alfredo,

Your results seem correct; it is true that most Rb have worse
short-term performance than a free-running OCXO. I think
2.5e-11 is about right.

How did you measure yours?

Yes, the TBolt OCXO is quite good, short-term. The ones sold
by TAPR (tested here by me, last year) are 1 or 2 to 3 e-12,
so all are about 10x better than your LPRO's.

Short-term frequency stability, and long-term stability, and
hold-over timekeeping, or price are all different goals; no
one oscillator meets all goals.

One question for you -- do all your 4 LPRO drift in the same
direction over time?

/tvb

>I control my lpro101 with trimble thunderbolt .
> now is more then one month , work good very stable .
> But I am not happy , sure long time is more stable of original 
> thunderbolt with ocxo , sure is more stable in holdover ( we need in 
> holdover ? i never lost gps signal ) .
> But short time is worst then original ocxo . I have 4 lpro101 , all four 
> have short time as datasheet near 2.5 E-11 .
> Maybe I am not lucky and my all lpro are not the best in short time , 
> but because my primary interest is short time , I  need to drive my 
> spectrum analyzer and my microwave generator with clean and stable 
> reference , the lpro not respond to this needs .
> I may send plotting at 12.8 GHz with ocxo and with lpro , there are to 
> much difference.
> I think you need to control your LPRO only if you are interesting to  
> control the drift of your lpro and use it as reference only for compare 
> , but not for drive microwave instruments.
> regards Alfredo