Comparison of beam-formed signal, before and after
Day 245, 2001
log of Nov. 4 2001
Data from one 2-hour data file from day 245 (September 2), 2001. The upper plot
shows the signal, digitized at 1000 Hz, from the VLA. The four channels
have been averaged, giving some horizontal directionality to the array.
The lower plot shows the signal after filtering through a pass band
centered at 260 Hz, about 2 Hz wide. There are Webb
signals at 245.1912 days (SS1) and 245.2325 days (SS3),showing up clearly in the
filtered signal but not at all apparent in the unfiltered signal. The
filtering also does a fairly good job of rejecting the various signal
spikes seen on the upper plot.