[evlatests] S&R failure statistics

[Bryan Butler]

What are the dates of the three observations?


Rick Perley wrote on 5/9/18 2:07 PM:
>      Ken asked if the 'set and remember' (= S&R) failures repeated from 
> one day to another, and how these failures were distributed over bands 
> and IFs.
> 
>      I've done the numbers, from my recent three science runs, all using 
> X through Q bands.
> 
>      1) Distribution over bands/IFs.
> 
>              Although these failures (defined here as the power to the 
> sampler low by a factor of two or more) occur at all bands and IFs, they 
> are uncommon *except* in the 10 -- 12 GHz IF band. (Uncommon is defined 
> as five failures or less out of the 27 antennas).  In the 10-12 GHz 
> band, more than half the antennas fail.
> 
> 
>      2) Distribution over time.
> 
>              The statistics failures are the same over time for the thee 
> runs.  However, it is not true that the same antennas fail each time. 
> Indeed, there is little to no repeatibility in which antennas fail to 
> have their powers set.
> 
>      One other point -- Xband Hi (10 -- 12 GHz) not only fails far more 
> frequently than any other, but the severity of the failure is also very 
> much higher.  I have an example of an antenna whose power was low by 
> nearly a factor of 10,000!
> 
> 
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