[time-nuts] another Ebay mixup, 5370

[Dr Bruce Griffiths]

SAIDJACK at aol.com wrote:
> Hi Tom,
>  
> this was the recommended setup (by HP) for checking the internal  noise. Feed 
> the 10MHz output back to the input using a short cable, and set the  unit for 
> "COMMON" input, setting 50 Ohm impedance etc.
>  
> In the meantime I did some more tests, and found the following:
>  
>    1) The sine-wave output is crappy. The sine wave has some sort  of 
> "Class-B" cross-over distortion, and it measures a whooping 200ps RMS jitter  on my 
> Wavecrest jitter analyzer (>400ps pk-pk). Compare that to 2.7ps RMS  jitter I 
> measure on our Fury 10MHz output. Definitely the crystal got damaged,  or 
> something else.
>  
> The unit has about 2x better jitter performance (around 50ps RMS) if I feed  
> a clean Fury 10MHz into it. I think the 10811 OCXO or the internal driver  
> circuit may have gotten damaged.
>  
>  
> thanks,
> bye,
> Said
>   
Said

Can you send an image of the rear panel sinewave output waveform?

Bruce