[time-nuts] HP/Symmetricom 58535A and 58536A

[EB4APL]

SAIDJACK at aol.com wrote::
> Hello Magnus,
>  
> yes, interestingly enough the units I have seem to have the option to power 
>  them through port-1 removed by brute-force: the inductor on all my units 
> has  been ripped off the PCB by force!
>  
> This holds for the 1-2, 1-4, and 1-8 Agilent/Symmetricom splitters I have,  
> all of them have this rather rude modification made (and they are all from  
> different sources, and vintages).
>  
> Thus port-1 has no DC load at all, while all the other ports have a DC load 
>  to ground for the GPSDO.
>  
> Maybe this is the problem, I need to see if the Thunderbolt works with or  
> without a DC load..
>  
> I am glad I am not the only one having this issue with the Thunderbolt  
> though.
>  
> One more tidbit on the side: it is not a good idea to mix-and-match GPSDO's 
>  that have different antenna voltages (5V and 3.3V for example) on a 
> passive,  DC-coupled splitter. This will create a problem. And can also lead to 
> some  really interesting results:
>  
> I have a USB eval board from a Taiwanese company, and noticed that it  
> generated a 1PPS without the USB being plugged-in. Very strange.
>  
> Turns out the board is getting power and running perfectly well from  
> another GPSDO connected to the same passive antenna splitter, and being fed  
> power from it's own antenna input!!
>  
> bye,
> Said
>   
>   
Hi,

It reminds me when I was breadboarding a TVB divider for my Rb clock 
project.  Once I removed the power to the PIC, but the 10 pps led 
continued blinking at a very low intensity.  After minutes of  
stupefaction and a search for a charged capacitor or other power source, 
I realized that the beast continued working powered by the 10 Mhz signal !!!

Regards,
Ignacio Cembreros