[evlatests] Abnormal reported Tsys values

[Barry Clark]

Rick Perley wrote:
>     The system temperature is calculated from the following (which 
> presumes a linear response with zero offset):
> 
>     Tsys = Tcal * Poff/(Pon-Poff)
> 
>

[snip]

>     Antenna 7 at L-band.  Tsys ~ 70K, which I am sure is real. 
>     Antenna 15 at L-band:  Tsys ~ 150 K, which is certainly real. 
>     Antenna 24 at L-band:  Tsys ~ 5 K, which is certainly *not* real!  
> This antenna is known to have an unusually (and deliberately!) high 
> Pcal, so it seems clear that the problem is the Tcal listing is about a 
> factor of 5 too low. 

Error in TcalLoad procedure - fixed.

>     Antenna 28 at L-band:  Tsys ~ 20K, which seems too low to be 
> believed ...
Serial number 26, Tcals measured 2008-10-28 I think.

>     Antenna 8 at S-band, in A/C only:  Tsys ~ 10K.  This must be a Tcal 
> listing error.
>     Antenna 9 at S-band, in AC only:  Tsys ~ 110 in A, and 66K in C -- 
> clearly a Tcal error.
>     Antenna 10 in S-band, in AC only:  Tsys ~ 50K.  Again, a Tcal error.
>     Antenna 15 in S-band, in AC only:  Tsys ~ 90K, again a Tcal error.
>     Antenna 24 at S-band, in AC only:  Tsys ~ 10K.  ditto
>     Antenna 27 at S-band, in AC ony:  Tsys ~ 15K, ditto. 

For all the S band antennas mentioned, the tcals in the database agree
with the ones in the techdocs area.  Something is screwy somewhere
(swapped identities perhaps?)
Data base says antenna 8 has receiver 004
                        9              p02
                       10              009
                       15              006
                       24              003
                       27              005
>     Antenna 16 at C-band in BD ony:  Tsys ~ 14K, clearly at Tcal error. 

Old receiver - nothing sensible out of here.

>     Antenna 2 at X-band in all IFs:  Tsys ~ 13K (AC) and ~20K (BD) -- 
> probably Tcal error.
>     Antenna 9 at  X-band in all IFs:  Tsys ~ 20K, which is likely a bit 
> lower than real. 

Tcals were measured a long time ago for antennas 2 and 9.

>     Antenna 16 at X-band in all IFs:  Tsys is very high:  180 in A, 650 
> in C, 130 in B, and 220 in D.  These are correct, as the elevation 
> effect is completely drowned out in the receiver noise. 
>     Antenna 22 at X-band, all IFs:  Same situation as antenna 16, but 
> not as severe:  Tsys ~ 70 in AC, and 130 in B/D.
>    
> 
[snip]
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