[evlatests] An example of why we should apply switched power

[Rick Perley]

     In the switching tests, a spectacular case of how switched power 
can help has been found.

     At C-band, during the last 30 minutes of the test, ea02 developed 
large, sinusoidal gain variations.  Although both RCP and LCP showed 
this, the LCP is much the larger.  The period is about 1 minute, the 
power amplitude about 9%.  In RCP, the variations are much smaller, 
about 0.8%, and are *exactly* out of phase with the LCP variations.

    Blind application of the switched power was done, which completely 
removed the cyclical variations.

     Attached are the CALIB solution gains, the first without switched 
power applied, the second with.

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