[time-nuts] homebrew counter new board test result

[Magnus Danielson]

Tom,

On 02/27/2015 01:18 PM, Tom Van Baak wrote:
>> 2) Does any one have the test data of 12 digit/s counter when DUT=REF?
>> I want to know the gap between mine and a  commercial counter.
>>
>>
>> Thanks
>>
>> Li Ang
>
> I did a lot of testing of 53132A counters a while back to research how well the interpolators worked and to measure the interference when CH1 gets too close to CH2. There was some discussion on the list about this at the time.
>
> For the context, see: https://www.febo.com/pipermail/time-nuts/2014-April/084670.html
> For the plots, see: http://leapsecond.com/pages/53132/
>
> A good paper to read about the trouble when DUT is close (or "equal" to REF) is:
> http://literature.cdn.keysight.com/litweb/pdf/5990-9189EN.pdf
> "Isolating Frequency Measurement Error and Sourcing Frequency Error near the Reference Frequency Harmonics"

Nice reading and illustration of the problem. It does not go into 
explain where these errors come from.

I especially like that he worked on an offset frequency to handle source 
issues and that he elaborates with both time-base time and frequency 
offset, as well as average and peak-to-peak values.

Have you seen any papers going into depth about that?

Enrico have been looking at post-processing filtering, and it's effects.

I just haven't seen any paper giving much about how cross-talk and such 
affects non-linearity and post-processing such as frequency reading and 
ADEV. I have my own model from experience and various sources, but not 
seen anything comprehensive.

Cheers,
Magnus