This is an old revision of the document!
At this stage the antenna should still be in the stow position (Az = 1, El = 88).
Before moving the antenna, check that the area surrounding it is clear of obstructions. This is best done via the live web cameras so that you can be sure the image is current. The username is observer and the password is the usual one:
If you need to power cycle a web cam (to try and ressurect it), this can be done for Katherine and Yarragadee through their internet power switches (username is admin, password is the PCFS root password).
Click on the “Boot” radio button next to the device you want to power-cycle, which is “Camera”, and click on Apply. Be very careful that you boot the right device!
At Hobart and Katherine you can check the status of the backup generator via the System Monitor interface. The default mode is “In Auto, off” which means it's ready to turn on if there's a power failure but it's currently switched off. If it's in any other state, query it with the On Call person.
The antenna Controller (in the pedestal) gets its time from the NTP server on the local GPS CNS-II clock. If it doesn't know the time, it can't point the antenna. Check the System Monitor display and make sure “Controller clock” is OK. If not, there's a problem. Check the HMI interface on time[hb|ke|yg] and look for the “Current time” section half-way down the right-hand side. MJD should be correct and the seconds should be ticking over. You should also see CLOVK INITIALIZED and SNTP SERVER OK with green backgrounds. If this doesn't look right, consult the On Call person.
Check the System Monitor that the Drive control is in “Remote”. If it isn't you won't be able to move the antenna. Cann the local support person at the site for assistance.
In the field system:
proc=point initp
Then choose a source from /usr2/proc/point.prc (e.g. 1618m49, hydra, virgoa, etc). (The monan display can be started if you want to check the sidereal time.) Sources to choose from:
Source RA Dec pictora 05 19 49.7 -45 46 44 1921m293 19 24 51 -29 14 30 0857m43 08 59 27.1 -43 45 09 eso212 09 24 24.2 -51 59 29 1618m49 16 22 12 -50 05 51 0521m365 05 22 58 -36 27 31 virgoa 12 30 49.449 12 23 28.17
Just type in the name of the source you want. e.g.:
1921m293
When the antenna gets on source, start the pointing check:
fivept
Be prepared to wait for 5 to 10 minutes for a result. Fivept does step-by-step offsets (9 points each) in Elevation, the Azimuth. It will probably try again if it fails the first time. When finished, look for the third and fourth numbers xoffset. These are the pointing offsets in degrees. For a more detailed description of fivept
see Fivept Output: What does it mean? but briefly, you should see something like this:
Az El Lon_offs Lat_offs 2013.043.22:40:13.21#fivpt#xoffset 210.7833 5.4745 -0.00319 0.02518 0.01481 0.00850 1 1
Where Az
and El
are the antenna Azimuth and Elevation that the fit was done, Lon_offset
is the cross-El pointing offset in deg and Lat_offs
is the Elevation pointing offset in deg.
Total pointing offsets should generally be less than ~0.02 degrees. Offsets greater than 0.04 are considered to be critical and require immediate investigation. Pointing offsets less than this should be dealt with as soon as possible after the observation.
A SEFD check can be made using the new pointing offsets with a
onoff
Zero offsets with
azeloff=0d,0d
And revert to the nominal DBBC Conditioning Module target power levels with a
proc=<experimentcode><station> setupsx
At the moment the PCFS does a good job at pointing checks but not so good with SEFD (DBBC issues). Here's an alternative method that may produce more reliable SEFD estimates as it uses the broadband power meter.
On the pcfs machine, run /usr2/oper/prePoint.sh
. This script will automatically select a source and carry out a series of three grid-pointings on the source and report back some information on the measured offset and source amplitude. If the source is recognised as a standard flux calibrator, it will also report back and estimated SEFD at X-band. It will then select another source and carry on until instructed to stop.
An example of the output of the script is included below.
oper@pcfshb:~$ ./prePoint.sh Please note that the first scan is usually unreliable... Selected source is 0857-43 0857-43 2.54602558e+02 6.20529151e+01 -7.18278453e-03 -1.18138754e-02 5.71477606e-02 8.07570616e+00 2.54504080e+02 6.18303305e+01 -1.71352319e-03 -1.01823932e-02 5.24651895e-02 8.09241828e+00 2.54408601e+02 6.16153978e+01 -6.02304403e-03 -9.01833893e-03 5.38752057e-02 8.07611965e+00 Type a message & press enter to stop AutoPointing... Continuing... Selected source is 3C353 3C353 - X-band 6.87293690e+01 2.27332023e+01 -2.35926560e-03 -2.64216019e-02 -5.39766563e+02 -1.36228380e+05 3360 6.84840694e+01 2.29447284e+01 -1.24883255e-02 -4.65807716e-03 3.30921926e-02 8.45462290e+00 3403 6.82383931e+01 2.31555810e+01 3.51911062e-03 -2.47805389e-02 3.26169632e-02 8.47415431e+00 3460 3C353 - S-band 6.79819576e+01 2.33745982e+01 3.13166250e-02 -2.27306091e-02 -1.24692372e+01 -1.25976266e+03 4016 6.77250691e+01 2.35929034e+01 -3.30836441e-02 -1.97442791e-02 2.18987395e-01 2.15648178e+01 3915 6.74621249e+01 2.38152119e+01 -1.33919869e-02 -8.66837313e-02 2.09943492e-01 2.13562383e+01 4044 Type a message & press enter to stop AutoPointing... stop Continuing... oper@pcfshb:~$
After each source title, the three outputs of each pointing observation are reported. The columns are Azimuth, Elevation, Azimuth offset, Elevation offset, source amplitude, Tsys. The units are degrees for azimuth and elevation and both the source amplitude & Tsys are reported in units of the CAL. Total pointing offsets should generally be less than ~0.02 degrees. Total pointing offsets greater than 0.04 are considered to be critical and require immediate investigation. Pointing offsets less than this should be dealt with as soon as possible after the observation.
For sources which are recognised as calibrators (currently Virgo, Hydra, 3C348 & 3C353) there is a seventh column which reports the SEFD, estimated from the source amplitude. For these sources, there will be a second set of observations performed using the S-band system. The pointing offsets from these observations are best disregarded.