reported power level jumps in beam5b on 12sep10. The tsys did not
The plots show pwr vs time for a2010
11sep10 to 14sep10 (.ps)
- All scans lasting 600 seconds between 11sep10 and 14sep10
(morning) were selected.
- The median power for each scan for each beam was then computed.
- the requested wapp attenuator value was also extracted for each
- Page 1: beam 5 power vs time
(averaged to 600 second scans).
- Top: bm5A median
scan power vs time. The dashed red lines show the start of each
observing run. The x axis is cumulative 600 second scans for the 4
days. The each point is the median power for a 600 second scan.
- 2nd: The wapp attenuator value for beam 5a. It remained at 4db
for the entire time.
- 3rd: bm5B median scan power.
- You can see the jumps in the power during 12sep10. During
this period the attenuator had been commanded to 4db.
- 4th: the bm5b wapp attenuator value.
- it was set at 5db for 11sep10. At the start of 12sep10 it was
set to 4db. after 12sep10 it returned to 5db.
- Page 2: beam 5 power vs
time. 1 second resolution for the first 2 hours of 12sep10.
- top: beam 5a.
- bottom: 5b
- You can see the power jumping and then drifting for first 2
- Each night at the start of observing, the wapp attenuators are
adjusted, and then left fixed for the entire observing run (about 6
12sep10 wapp 5b attenuator was set to 4db (all other days it was set at
- Initially the power was 1db higher than the 5db setting (.95 to
1.15). It then drifted and jumped until it ended up at 1.4 This was
about 2db above the 5db setting rather than 1db.
- It remained at this higher level for about 5 hours.