A2390: galfacts commensal survey with Igalfa
may08
Intro:
A2390 is galfacts running commensually with
I-GALFA. The telescope is scanning in za at the meridian (10 to
12 minutes per strip) while using the 25 hz winking low cal. At the
turn around, the winking cal is turned off and the high cal is left on
for about 3 seconds.
Data is being taken with the wapps at 4 millisecond
dump time and 100 MHz bw. The center frequency is about 1415 MHz.
01may08: high cals not firing correctly..
The plot shows the total
power (beam0a) vs
time for the first 30 minutes of observing (.ps) (.pdf):
- Top: 1800 seconds of total power vs time:
- The dashed red line is the first turn around, the dashed
green line is the second turn around.
- 2nd: blowup of the first second of data taking. The high cal is
winking at 25 hz for about .25 seconds.
- 3rd: start of first turn around.
- there is a dropout and 681.5 seconds (dashed blue line).
- the high cal winks for about .5 seconds and there are no
cals.
- 4th: the entire first turn around period.
- from the dropout to the restart of the winking cal is about 13
seconds.
Conclusions:
- The high cal is not on solid for 3 seconds at the turn around
- Cause: the calport 3 command was not sent to select the wapp
input at the cal multiplexer.
- The high cal winks for about .3 seconds
- the program is switching from low cal to high cal before
turning of the winking cal.
processing: x101/080501/a2390.pro
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