Beam5a dropout 27sep11
- The observer asked the operator to turn off beam5a.. which the
Project A2010 (alfalfa) reported rfi in beam5a
on the evening of 27sep11 using alfa. The problem looks
like a dropout of signal power. The setup was:
The bad data was seen in file:
- alfa receiver centered at 1385 MHz.
- Drift scans for 601 seconds (with cal at the end).
- wapps at 100 MHz bandwidths, 3 level.
- 1 second integrations
the plots showfile 0022. the total
time for this scan (.ps) (.pdf):
- started about second 540 in bm 5a.
- It finished the integration around 22:00 27sep11.
This could be alfa or it could be the wapps (maybe the programmable
attenuator on wapp3).
- Page 1: total power vs time for 600 second scan
- top pola, bottom: polB
- Colors show the different beams
- Bm5a drops out at the beginning and around 435 seconds.
- polB has no problems.
- the 12 second blibs are the faa radar at 1350 MHz.
- Page 2: Blowup of total power vs time for the dropouts.
- Top: dropout at the start
- Bottom: dropout 435 to 526 seconds.
- Moving up and down, there is a 1 second integration with 1/2
- This could be from a slow transition , or a rapid transition
at .5 seconds.
- Coming back up at 526 there were a few seconds at the top
before it leveled out.