[evlatests] switched power issues

[Ken Sowinski]

On Thu, 26 May 2016, Barry Clark wrote:

> That was a bad suggestion.  Rick sees an actual decrease in pdiff,
> not just a change of slope.  But, another question.  Do we need to
> worry about the receiver noise from the P band receiver leaking into
> S and raising the Tsys?

I asked myself this question when I read Paul's message and decided
the answer was we don't care.  As long as the extra contribution
is constant in time, and independent of total power in the
receiver in use.  The increase in T_sys is mo more than 0.1*0.05/2,
about a quarter of one percent.  Does that matter?