[evlatests] focus and antenna 14

[Kerry Shores]

I double-checked the various diagnostics for all of Ant. 14.  Only odd 
thing I could find is the bandpass shape (FFT window) for IF B is 
clearly different from the other 3 IF's.  In general, the bandpass 
shapes match fairly well.  Could find nothing wrong with IF D, even 
after more resets.  I had reset all DTS modules in Ant. 13, 14, 16 
earlier today and made sure they apppeared to be behaving.  They still 
seem to be behaving...

Ken Sowinski wrote:
> I verified that the methods put in place to deal with 
> focus offsets and the focus-elevation curve seem to  work 
> in a mechanical sense.  Both can be set and controlled from 
> the observe script.
> 
> subarray.setFocusOffset() works like subarray.setAz/ElOffset(),
> units are cm.  This can be used to implement a "focus finding
> mode" analogous to the existing pointing modes.
> 
> subarray.setRefocus() works.  The parameter is 0, don't,
> or 1, do refocus.  The coefficient of sin(El) comes from
> the database, is band dependent, but the same for all antennas
> at each band.  Currently X band is set to 0.55 cm and the rest 
> are unset.  We should be in reasonable shape if values are entered 
> for K and Q bands and the primary focus values for each antenna 
> adjusted.  Once a focus finding mode, and a version of telcal that 
> does focus are in place we can try an observation to measure the
> focus curve.
> 
> Something funny happened to antenna 14.  Fiber to all antennas was
> disconnected this morning, but antenna 14 did not come back properly.
> That was traced to a known L305 problem at that antennas which requires
> cycling power to the L305 to make it reacquire proper lock.  This was
> done, and the antenna sort of returned.  The problem is that the 
> delay changes for some IFs are much to large to be reasonable.
> A -106 ns
> B  -38
> C    0
> D  ???
> The change in IF D was so large that I did not take the time to try
> to find it.  If B, even with the -38 ns change is still down by about
> a half in power compared to IFs A and C suggesting that there might
> be something wrong with the BD IF pair.  The change to delays for IFs
> A and B were made only for X band.  Is it possible there is still 
> something not quire right in the DTS modules after all the resets done
> today?
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