[evlatests] 2GHz-wide 3-bit wideband data

[Michael Rupen]

Rick, is your impression that the noise is the same (high value) for
all subbands?  i.e., sb 12 is representative, and it's not that we were
previously looking at (say) sb 04 and that is less noisy than sb 12.

               Michael


> Michael/Ken took 40 minutes of full wide-band data with the 3-bit
> samplers.  Data quality looks very nice, with uniform delays, continuous
> amplitudes/gains across all 16 subbands.
>
> But the rms noise is far higher than it should be.  In subband 12 (6928
> MHz -- same as the simple test done by Ken a little earlier), we have
> for our 'noise matrix':
>
>             12            15              22               28
> ------------------------------------------------------------
> 12         XX          .41            .75             .51
> 15         .32           XX           .74             .50
> 22         .38           .45            XX            .99
> 28         .43           .49            .57               XX
>
>    The matrix entries (says here) should be 0.15!  So we are a factor
> of 2 to 6 too high.
>    Perhaps more interesting is that the entries for the baselines
> amongst 15,22,28 are three times higher than they were for the simple
> 1-subband test done by Ken a little earlier.  It's as if all noises have
> been multiplied by three.
>
>
>
> Michael Rupen wrote:
>> The file name should be C3tune_3bit2GHz_000.
>>
>>                   Michael
>>
>>> We have a full 2 GHz of 3 bit sampelr data with four antennas:
>>> 12, 15, 22, and 28.
>>>
>>> 2132 UT  Start script
>>> 2135     finish adjustments
>>> 2207     finish script
>>>
>>>
>>> Ken
>>>
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