I bought one of these (https://www.ebay.com/itm/GPSDO-10M-Output-GPS-Disciplined-Oscillator-Clock-Sinusoidal-Wave-RS232-US-SHIP/172933685909?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649) a couple of months ago. I only have a 9-digit frequency counter to measure it with, and the counter only has a 1 ppm TCXO, but, subject to those constraints, it's been rock solid. Lot less expensive than a Trimble. Interior photos here (https://www.eevblog.com/forum/testgear/bg7tbl-gpsdo-master-reference/msg2457417/#msg2457417).
Karl -----Original Message----- From: time-nuts <[email protected]> On Behalf Of Don Meadows Sent: Friday, June 21, 2019 7:28 AM To: [email protected] Subject: [time-nuts] GPSDO 10MHZ Splitter I don’t have a GPSDO yet, I just can’t decide on one. I am leaning to the Trimble, but it’s still undecided. Could anyone comment on buying a “Refurbished by Seller” GPSDO on E-bay. They are a few dollars cheaper, but I really want one I can have trust and confidence in. Sorry for the long post. Thanks, Don Sent from Mail for Windows 10 _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there. On Sat, Jun 22, 2019 at 3:00 PM -0700, "Hal Murray" <[email protected]<mailto:[email protected]>> wrote: [email protected] said: > Given the relatively low cost of a GPS based “Stratum 1†NTP, it’s not > real > clear why (at the end of the paper) they go off and “exchange emails > individually with the organizations that run stratum 1 servers, as well as > negotiate permission to use them.†to source the root time for the system. > I > would have thought that some sort of combo of on site and off site sources > would be at the “top of the treeâ€. I have no inside information... Maybe reading between some lines. It's a tangled mess. Some of their 180 sites do not have stratum 1 servers and/or they may want to use external stratum 1 servers for sanity check and backup. Many sites with stratum 1 servers do not want the load they would get from general public access but are happy to allow access for a good reason. Negotiating that access would probably involve email. They are using (old) shared key authentication. (probably because the servers they want to talk to don't support NTS yet) That requires out of band communications to setup the shared key. Email is probably the most convenient way to do that. -- These are my opinions. I hate spam. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
