[evlatests] Bad SPW

[Rick Perley]

The situation is a bit less clear than I originally communicated:

There is a difference between the polarizations:

a) In LCP, SPW44 (in Ku-band) has no signal at all, while adjacent SPWs 
are fine.

b) in RCP, SPW44 is also without signal, but adjacent SPWs (from 33 to 
48) are highly attenuated.  Calibration recovers the signals in these 
other SPWs, without apparent loss of SNR.

Rick

On 7/1/23 15:30, Ken Sowinski wrote:
> On Fri, 30 Jun 2023, Rick Perley wrote:
>
>> And I can confirm the problem (no correlations in SPW44, in Ku-band, 
>> for ea17 only, on all polarizations) is still with us.
>
> Just to be clear, does "all polarizations" means both pols of all If 
> pairs
> or just both pairs of one IF pair?
>
> Ken
>
>
>> On 6/30/23 12:03, Ken Sowinski wrote:
>>>  On Thu, 29 Jun 2023, Rick Perley via evlatests wrote:
>>>
>>>>  In reducing some data  taken over the past week or so, I note that a
>>>>  single spectral window, at Ku, K, and Ka bands, gives only noise 
>>>> -- no
>>>>  coherent signal visible in either polarization.
>>>>
>>>>  The SPW is:  #44 in Ku band
>>>>
>>>>  and              #21 in both K and Ka bands.
>>>>
>>>>  The problem is not need in the low frequency bands (L though Ku).  
>>>> Q-band
>>>>  was not observed.
>>>>
>>>>  The problem was in every database taken since june 22.
>>>
>>>  This didn't get as much attention as your complaint about ea27.
>>>
>>>  If, as it appears, this affects all antennas then it sounds like
>>>  a bad, or misconfigured, baselineboard.  Other possibilities are
>>>  the network switch or CBE, but a bad blb is much more likely.
>>>
>>>  Ken
>>
>>