[evlatests] EA14 polarization and VLITE

[Paul Harden]

We swapped the polarization Thursday on VLITE antenna 14 and should now 
be correct.

Here's the problem.  Nomenclature for the low band linear polarization 
has been standardized such that:
Horizontal antenna = RCP
Vertical antenna = LCP

The input connectors on the VLITE module are labled "Ch. 1" and "Ch. 2." 
  There is no indication what polarization is assigned to what channel. 
  The 50/50 choice used was obviously wrong.

What polarization is assigned to Ch.1 and Ch.2?

When installed, RCP was connected to Ch. 1 and LCP to Ch. 2, which 
caused the reported swapped polarization.

LCP now goes to Ch. 1
RCP now goes to Ch. 2

This channel assignment needs to be standardized, and perhaps some "LCP" 
and "RCP" labels made to eliminate the channel references.

Also, there are two 30dB coaxial amplifiers on the Ch.1 and Ch.2 inputs 
on the VLITE module, amplifying the low band receiver output by 30dB. 
Typical LBR receiver output is about -75 dBm/MHz on the cold sky, 
meaning about -45 dBm/MHz input to VLITE.  I don't know how much 
internal amplification there, the ADC range, or the compression points, 
but seems this much amplification would seriously limit the dynamic 
range and gain headroom of the VLITE module.

Paul