[evlatests] Bad Tsys and Tcal values

[Rick Perley]

    A quick review of the reported system temperatures reveals a few 
problems, mostly with the tabulated Tcal values.

    Q-Band:  Tsys is claimed to be 20K on the A and C IFs. (We wish!).  
The problem is in the Tcal values, which are listed as 1K.  (Curiously, 
the Tcal values for the BD side are find). 

    X-band:  Tsys is between 750 and 1000 K on ea05.  These look like 
the truth, based on system noise. 

    U-band:  Tsys is claimed to be 10K for ea12.  The problem is with 
Tcal, which is listed as 1.0 K. 
                    Tsys for ea21 is between 50 and 60 -- looks like the 
truth.  This is two times too high. 

    S-band:  Lots of problems here. 
                  ea07 has a (probably real) Tsys of 100 to 250 K. 
                  ea15 has Tcals which are clearly 3 times higher than 
they should be (except for IF 'A', which is 300 times too high).
                  Antennas 16, 18, 21, 23, and 26 all have listed Tcal = 
1.0.  I guess these are newly installed receivers, and nobody has 
updated the Tcals from their default numbers.
                  ea22 has a claimed Tsys of 10K.  Here the problem is 
that the Tcal values are listed as 0.75 K or so -- clearly a factor of 2 
to 3 too low. 
                  ea08 has a Tsys of about 50 on the BD side. 

    L-band:  ea07 has a (real) Tsys of 75K. 
                  ea18, on IFs A and C have Tcal values of 1.0  Seems 
unlikely, given the derived Tsys = 20K.