[time-nuts] Cloudflare

[Karl Lautman]

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 <time-nuts-bounces at lists.febo.com> On Behalf Of Don Meadows
Sent: Friday, June 21, 2019 7:28 AM
To: time-nuts at lists.febo.com
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

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On Sat, Jun 22, 2019 at 3:00 PM -0700, "Hal Murray" <hmurray at megapathdsl.net<mailto:hmurray at megapathdsl.net>> wrote:



kb8tq at n1k.org 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 tree”.

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.