The driver circuit for the cal diode was modified to get rid of a cal instability (more info).  The cal deflection was remeasured on 14oct05.  The stability was checked, and the average Tsys was computed. The setup was:

• The telescope was parked at az=37 (dome side) ch=8.8 degrees (the lst was around 16:20 Hr).
• The cal was toggled on 1 sec, off 1 sec. This continued for 1050 seconds.
• 1 Mhz around 430 was detected with a 2 millisecond time constant and sampled at 1 khz.
• The median value for each 1 second was then used for the cal on, off

• Fig 1 top: Total power vs time for the cal on. These are the 1 second medians. The units are linear in power (A/D counts). The spikes are caused by  rfi.
• Fig 1 2nd plot: Total power vs time for the cal off.
• Fig 1 3rd plot: (CalOn-calOff)/(median(calOff). This shows the variation of the cal deflection in units of Tsys.
• Fig 1 bottom:Tsys vs time using 42.1 for the cal Temperature.

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