Differences

This shows you the differences between two versions of the page.

--- beamformer:20180817_obsnotes [2018/08/18 15:53] – bbarott
+++ beamformer:20180817_obsnotes [2023/10/28 18:36] (current) – external edit 127.0.0.1
@@ Line 14: / Line 14: @@
 *** S-Band ***
 [BF1]  1ax,1ay,1dy,1fx,1fy,1gy,1hx,2ax,2ay,2bx,2by,2dx,2dy,2ex,2ey,2fy,2jx,2jy,2kx,2my,3ex,3ey,3jy,3lx,3ly,4gx,4gy,4jx,4jy,4kx,4ky,4ly,5cx,5cy,5ex,5ey,5gx,5gy,5hx,5hy
 [BF2]  1ax,1ay,1dy,1fx,1gx,1gy,1hx,2ax,2bx,2dx,2dy,2ex,2ey,2fy,2jx,2jy,2kx,3ex,3ey,3jy,3lx,3ly,4gx,4gy,4jx,4jy,4kx,4ky,4ly,5cx,5cy,5ex,5gx,5gy,5hx
@@ Line 19: / Line 20: @@
 Beamformers #2 and #3 displayed many link errors that were not cleared by firmware reinit or hardware reinit. Further attempt was to drop all antennas on related iBobs from the hookup (i9,16,22,24). This appears to have cleared the link errors on the main nodes; did not clear link alarms on B15.bfa (recently repaired unit), which shows ERCS alarms on three FPGAs. However, this might be sufficient for Foxtrot obs (doesn't use b15). After some time link error also showed on BF3 link to i21. Was not pursued further.
+New antenna lists are:c
+(BF1) 1ax,1ay,1bx,1by,1dx,1dy,1fx,1fy,1gy,1hx,2ax,2ay,2bx,2by,2dy,2ex,2ey,2fy,2jx,2jy,2kx,2lx,2my,3ex,3ey,3jy,3lx,3ly,4ex,4gx,4gy,4jx,4jy,4kx,4ky,4ly,5cx,5cy,5ex,5ey,5gx,5gy,5hx,5hy
+(BF2/3) 1ax,1ay,1bx,1by,1dx,1dy,1fx,1fy,1gy,1hx,2ax,2ay,2bx,2by,2ex,2jx,2jy,2kx,2lx,2my,3ex,3jy,3lx,3ly,4ex,4gx,4gy,4jx,4jy,4kx,4ky,4ly,5cy,5ex,5gy,5hx
 #========== CASA Stability
 Took 30 snapshots each of crosses and outputs on CASA with all 3 beamformers.
-Activity directories are about 8:41am...
+Crosses activities:
+-8-18-8-41-4-BF1:
+-8-18-8-41-5-BF3:
+-8-18-8-41-7-BF2:
+Out activities are
+-8-18-8-57-52-BF1
+-8-18-8-56-34-BF2
+-8-18-8-56-24-BF3
+BF1: 5gx, 3ex,B2F4, showed significant drift over the integration. However, could be CASA.
+BF3: B1F3 very noisy. B2F4 some drift. B3F4 some digital - comb noise? B4F3 possible solar. Again, CASA?
+BF2: Similar
+Autos on BF1 and BF2 showed the comb seen in previous data and attributed by suggestion of Jon to the new feeds, but are otherwise unremarkable. Autos on BF3 show very poor roll-off response and are indicative that BF3 is at present unusable.
+Cross correlation results on 3c84, showing some solar interference, but otherwise maybe usable:
+-8-18-9-32-44-BF1
+-8-18-9-32-46-BF2
+Back to CASA as a sanity check:
+-8-18-9-53-47-BF1
+-8-18-9-53-48-BF2
+Have noticed in this and other runs that 5cx autos on casa in particular change amplitude significantly; network issue (soft start/stop, but ought be calibrated out with memtimers) or antenna issue?
+Phase calibration was difficult. During phase cal gave BF2 to Janusz to do hunt for 8 MHz comb. Eventually tried 5 minute calibration on 3c48 while setting; useful, but not totally enough to completely beat down the solar interference. Final cal used +0.2 caloffset, but probably mistake at this tuning (1660).
+Daytime calibration moving up to 6 GHz did show W3OH and g188.95m, but very weakly and didn't appear to be a good cal.