[time-nuts] The home time-lab

[Bob Stewart]

Hi Bob,
They're spikes.  So, what I'll do is just keep a test like this running for the next few days as I do other things.  I'll go ahead and put it back on internal clock, just in case.  If I see nothing, I'm going to have to conclude it's the power line.  If bad weather comes back and they happen again, once again I have to conclude it's the power line.  

I haven't taken the time to go through either unit.  I'll try to make some time for that in the next few weeks.

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

      From: Bob Camp <kb8tq at n1k.org>
 To: Bob Stewart <bob at evoria.net>; Discussion of precise time and frequency measurement <time-nuts at febo.com> 
 Sent: Thursday, July 7, 2016 10:17 PM
 Subject: Re: [time-nuts] The home time-lab
   
Hi

Have you been through the full alignment process on one or both of the 5370’s ? They are as much
an analog beast as they are digital. They *do* drift out of calibration / alignment / adjustment. When 
they go it’s usually not all of a sudden. They just gradually get worse and worse as the adjustments bake
away inside that hot box. 

===========

35 ns pops are pretty big. Are you seeing spikes or are you seeing steps? Spikes can be just about 
anything, including the next door neighbor’s bug zapper. Steps are a bit more indicative of something 
actually wrong. In either case, a counter with far less resolution than a 5370 can be used to help “triangulate”
the problem. A free running OCXO (or three) is also perfect for this sort of thing. 

Bob

> On Jul 7, 2016, at 10:16 PM, Bob Stewart <bob at evoria.net> wrote:
> 
> Tim,
> There is one variable that I neglected to mention in the first response.  I've been unhappy with the stability of the 10811s in both 5370s.  So, for this test, I'm using the 10MHz output from another one of my units to supply the clock.  In the past 71,000 seconds of the retest, I'm seeing a phase variance of only +60ps to -80ps in timelab with an "averaging window" of 0.
> 
> Bob
>  -----------------------------------------------------------------------------------
> GFS GPSDO list:
> groups.yahoo.com/neo/groups/GFS-GPSDOs/info
> 
>      From: Tim Shoppa <tshoppa at gmail.com>
> To: Bob Stewart <bob at evoria.net>; Discussion of precise time and frequency measurement <time-nuts at febo.com> 
> Sent: Thursday, July 7, 2016 8:16 PM
> Subject: Re: [time-nuts] The home time-lab
> 
> 1/35ns is about 30MHz. Is there anything in your clock chains that is ticking at 30MHz, such that a false count or slipped count induced by inductive disruption, would cause a 35ns phase jump?
> Related thread: https://www.febo.com/pipermail/time-nuts/2016-May/098028.html
> 
> Tim N3QE