[evlatests] 3-bit update

[Vivek Dhawan]

A follow-up on switched power:

Last time we did 3-bit tests, in September 2010, there was no switched
power data. Now there is.

The bad news: Tsys for the 3-bit antennas was higher (80-180K) than when
the 8-bit path is enabled (~25-30K).

The good news is that as levels and gain slopes were adjusted toward
optimum rms, Tsys improved dramatically.

The other bad news: in every single one of the files we have run so far,
the switched power data disappear after 5-10 minutes. All antennas drop
at the same instant. Bruce did not see anything on the station board
outputs to indicate anything amiss, but will look into it more tomorrow.

onward.


Michael Rupen wrote:
> We spent most of the day on 3-bit testing.
>