ATNF VLBI Wiki

Notes on Mopra operation for VLBI - From Tasso for the run of May 8, 2001

Will edit for notes soon:

1. Scheduled runs Mopra has C-band on Mon 7

        L-band on Tue 8

Mopra and ATCA have C-band runs May 13 (Sunday) and 14 (Monday).

The schedules for 7 & 8 are in the system. Others have not arrived yet from VSOP.

Robina should be able to do all but the 8th. For the 8th she will setup, help you gain control and go. Then WEW will change the tapeset at 9:40pm.

2. Schedules Only pitfall is the SCHED-type schedules for the ATCA and Mopra. At L-band they are identical. However, at C-band you MUST have 1Band=64 MHz at Mopra since that is the band we are recording. All else can be the same.

3. Tapes WEW will bring the tapes back from Mopra for 7 and 8th. For 13 and 14, you should arrange to get the Mopra tapes up to Narrabri (Robina is likely to forget). Then send the Narrabri and Mopra tapes back to Sydney and I'll take it from there.

4. Remote observing for Mopra VSOP run. It should be straight forward but the notes below may help:

a) VLBI stuff on v1mop This should be identical to Narrabri i.e. - You can start pcfs either by doing a “remote_pcfs” command (it starts a new xterm) or “fs” in an xterm on v1mop. - das1 starts the das. Beware colour tables and lock-files. - s2 mps2 should start a Mopra s2 terminal or just telnet to mps2.

b) Mopra correlator This is similar to Narrabri. Details on the Web from WEW on http://www.atnf.csiro.au/~wwilson/mpcor.html This gives you info how to run mpcor and recover from crashes, how to run dummsy (ds or tkds) for standalone operation and SPD to display (identical to ATCA). However, you'd only need the correlator for testing the setup and monitoring the bands during the run. It is not actually needed for the VLBI operation itself.

c) MOPRA VAX This may be the hardest if you are not used to it. It also has alogin limitation like NOEL, so it is better to start detached Decterms. Here is a recipe: - login to the VAX Mopra as VLBI (pword same as Narrabri VKBI account) - set host 0 and then login as observer (pword=same as v1mop=old atca) - in the login window type the following to create decterms:

set display/create/transp=tcpip/node=morpheus (or your machine)
create /term/detach

and repeat the last command to get more decterms. You'll want a minimum of 2, try for 4. You can create more from inside any of them. (If you get font problems, go to the DEcterm menu in Options, then Window and change the fonts to “Normal”. That should cure it). Then you can logout from the initial observer and VLBI direct login.

Now you have a few Decterms you'll need to run: 1. camon display to monitor the telescope. try /mopra-x to see the 2nd frequency (needed for L-band)

2. vlobs That starts the observing program. There is a help command to explain the commands available. Main one is: “file” to get a prompt for the name and then <schedulename> e.g w422d. This would get the schedule in, and start monitoring the Tsys. It does not do any setup yet but I think it tries to adjust the attenuators.

To start the schedule just type “start”. We usually put a scan in of the circumpolar source 1057-797 so there is some setup time. Once the scan is started, vlobs would run setup for the LOs and then adjust the attenuators if needed.

If all goes well that's all you'd need. If you run into trouble, type “stop” then “exit” and restart vlobs. It should retain the schedule so all you have to do is say start.

3. There are other programs like - “lo_setup” for setting the front ends - “a_test” for fiddling with attenuators or other parameters - “mmdrive” for injecting test tones. These are only needed at setup time. Some instructions are in the long setup emails I send Robina. Hopefully you'll not need these.

If you get stuck try Dick or John. I'm on the mobile (0409 447 902) but I'll be 8 hours behind you.