[time-nuts] Measuring ADEV using TBolt-Tic tester

ws at Yahoo warrensjmail-one at yahoo.com
Fri Oct 7 20:16:33 UTC 2011

What was the RMS and PP phase noise for your 8e-14 test?

Something to keep in mind is that although the Z3801 has a better Osc than 
the typical Tbolt.
Long term, really low noise is all about the quality of the GPS signal and 

The Z3801's GPS engine is far inferior and not even close to the 10 to 100 
ps, 1 sec noise that a Tbolt engine has.
So how much does that effect the mid term GPS Phase noise which is highly 
dominated by how good of antenna system one has.
Sounds like comparison is needed.


Some test like these are on my list for this winter.  I am planning to look 
at a Z3801A versus a couple of 5061 class units: one with a high stability 
tube that I think is in very good condition, and another with an FTS 
replacement tube of probably typical surplus quality.  I can also add a 
TBolt into the mix.  I'm hoping to lash up multiple 5334 counters in TIC 
mode so I can do several comparisons simultaneously.

In an early test of the 004 tube vs. Z3801A over a week or so, I saw what 
looked like a floor in the 8e14 range.


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