[evlatests] P-band checkup update

[Paul Harden]

On 7/18/2016 3:43 PM, Frank Schinzel wrote
 >  The worst from this observation are: ea06, ea27, ea17, ea15

 >  It would be great to look into the worst misaligned dipoles, of 
which none have the new style P-band dipole mounting jam nut and to 
identify the reason for the strong bandpass ripples on ea28X.

Sandra and I visited the above antennas to check the P-band dipole 
alignments.  Most are off by quite a bit.  A .pdf file is attached with 
photos of the above dipoles to show the degree of misalignment.  We'll 
attempt to realign these in the field next week.

For what it may mean, all of the worst above dipoles are on the north 
arm.  Coriolis effect from the Earth's spin? :-)

None of these antennas have the new style mounting jam nut.
Those are located on antennas 01, 08, 20, 22, 24

We could not detect any noticeable ripple on EA28 at the antenna on the 
receiver outputs.  We also pointed EA28 to the sun to plot bandpasses 
and still could not see any >1dB ripples on X (LCP). (Note: EA28 is also 
on the north arm!)

Lastly, Jerry fixed EA01 today such that the low band CAL is switching 
at 10 Hz again, vs. 20 Hz.  That should move Pdiff off of zero.

I will be gone through next Wednesday on vacation.  If any questions, 
ask Sandra.

Paul


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