Hi Scott,
I do understand the reasons that these users want this quality of output.  It's 
who these users are, what fields, industries, etc, that I didn't quite 
understand.
Bob -----------------------------------------------------------------
AE6RV.com

GFS GPSDO list:
groups.yahoo.com/neo/groups/GFS-GPSDOs/info

      From: Scott Stobbe <scott.j.sto...@gmail.com>
 To: Bob Stewart <b...@evoria.net>; Discussion of precise time and frequency 
measurement <time-nuts@febo.com> 
 Sent: Sunday, December 18, 2016 8:22 PM
 Subject: Re: [time-nuts] 1PPS users?
   
Part of the reason 1PPS needs to be so clean is because you are continuously 
integrating phase noise of the LO (hopefully an OCXO). While 10 uS is pretty 
trivial off a gps receiver. Without gps, 10 us over 24 hrs with a plane jane 
AT-cut crystal subject environmental dynamics becomes ludicrous. More than 
likely the short term stability of GPSDO is cleaner than it needs to be for 
many applications, but that is so holdover over an hour or day remains 
reasonable.
On Sun, Dec 18, 2016 at 6:16 PM, Bob Stewart <b...@evoria.net> wrote:

One thing I've never really understood is who actually uses the high-quality 
1PPS output from a GPSDO.  I have spent a lot of time, effort, and money on 
developing my GPSDO without a whole of thought to the user base.  It was just a 
quest for the best result I could obtain with a particular technology.  The 
frequency standard users was a no brainer.  Everyone who wants a frequency 
standard eventually understands they need to get a GPSDO, or an Rb, or a Cs.  
And that's all I thought I had: a good frequency standard.  And then Tom 
prodded me a bit and showed me the shortcomings of what I was doing, and I did 
something about it.  So, if an NTP user can get his time fix directly from a 
noisy receiver, who actually needs a time-accurate, low jitter 1PPS pulse?
Bob - AE6RV
 ----------------------------- ------------------------------ ------
AE6RV.com

GFS GPSDO list:
groups.yahoo.com/neo/groups/ GFS-GPSDOs/info
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