[evlatests] antenna 24 returns

[Ken Sowinski]

Rob reported Friday that antenna 24 was usable again and that
L and C bands ought to work.

X band was examined first.  A large delay change of about -80 ns
was required.  This is rather more than I expect simply from
swapping D racks.  Perhaps all cables are not equal?

C band works.  Delays are set reasonably well for IFs A and B;
more work is needed for C and D.

L band works also, but the polarizations are reversed.  Delays
have not yet been set.

BD attenuator settings have been entered for L and C bands.
Focus has not been examined yet for L and C bands.