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 In a message dated 11/1/2009 03:19:14 Pacific Standard Time, [email protected] writes:
> The amp is followed by a resistive splitter, and possibly a resistive > attenuator (on the 2-port version). Then a cavity filter, then the N-Connector, > very simple, not much that can go wrong. They do have DC load on the non-DC-thru ports. Check the open/short status on the thunderbolt. It's very easy to see with the Thunderbolt monitor program. Cheers, Magnus _______________________________________________ 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.
