[evlatests] C and X Wideband Tests

[Rick Perley]

    And, upon further review ...

    Antenna 18 is exceptionally unstable, from record to record (1 
second averaging) in both amplitude and phase, at C-band.  It looks fine 
at X-band. 

    Antenna 23 had major phase jumps between calibrator observations, at 
both bands and for both frequency tunings within c-band. 

   

Ken Sowinski wrote:
> On Sun, 1 Aug 2010, Rick Perley wrote:
>
>>    Problems common to all three tunings:
>>
>>    a) All 8 subbands from antenna 11, IF 'B' had a very incorrect
>> passband.  There are 'suckouts' appearing between the 2nd and 3rd
>> subbands, and between the 6th and 7th.
>
> No hint of this this morning using OSRO.
>
>>    b) All data from antenna 22, IF 'B' were integer zero.  (No data
>> delivered).
>
> This is a DTS problem under repair as I write.
>
>>     c) Antenna 27 requires a huge delay correction -- about 55 nsec.
>
> It was about 40 ns this morning; was OK on Friday.  What would
> change the delays by this much for all IFs?  Fixed as pad delay.
>
>>    Problem specific to C-band:
>>
>>    Antenna 16, IFs A and B (RCP) gave no fringes -- only noise.
>
> It looks dead.  RCP at X band is weak as well.
>
>>    Problems specific to X-band:
>>
>>    a) Antenna 7 gave no fringes (as reported by Ken, I believe).
>>    b) Antenna 9, IFs C and D (LCP) gave no fringes -- only noise.
>
> b) is a long standing problem.
>
>
> In addition, I note that ea17 has a large T_sys at C band,
> and ea05 at K band.
>
> ea20 still has a large pointing error after the encoder work
> last week.  Some pointing scans should be mined to find the
> correction.