[evlatests] Phase vs. elevation; phase jumps.
Vivek Dhawan
vdhawan at nrao.edu
Mon Nov 27 17:01:40 EST 2006
Results from the 'baseline' run, Nov 27, X-band, 5 hours.
Phase variation with elevation:
EA 13, 14, 16 still cannot fit an improved position.
EA 23: only one IF, A. Amplitudes about 50% or lower.
and phase vs. el. worse than the others.
EA 26 (Durand was particularly interested) worked pretty
well - fringes of the right strength on all 4 IFs.
Phase vs. elevation is poor - like many EVLA antennas.
EA 18 and 24: continue to behave well re phase vs. elevation.
But see next item.
Phase jumps:
There are 3 occasions when the phase jumps by over 100
degrees, then jumps back again some minutes later.
The jumps are on all IFs, and are very clear on 18, 24.
They are partly masked by the elevation variation on
13, 14, 16; and completely masked on 23 and 26.
The data are consistent either with all EVLA antennas
OR all VLA antennas having the jump.
Vivek.
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