[evlatests] antenna 14

[Ken Sowinski]

Antenna 14 sort of works now.

14C is dead.  It wants about 40 dB of attenuation to
get the sampler RMS down to where we want it and that
seems like about 20 dB too much.  No correlated signal
at all, but the SD voltage seems normal.  I guess, but
have little evidence, that somethins is wrong in the 
downconverter.

In general the antenna performance seems somewhat worse
at the smapler input levels that Mike prefers.  A more
careful check will be made later.

It appears that with one gain parameter we can take our
choice of underdriving the T4 or overdriving the requantizer
in the transition module.  Three of the three working IFs
have the ALC pegged, or close to pegged, when the sampler RMS
is ~2.25.  Providing more drive to the sampler input helps,
but requantizer overflows are reported.  This too will have to
be looked at more carefully and checked with antenna 16.