====== Following on with another observation ======
Sometimes, another IVS observation will follow from the one just finished. In this case, some of the setup procedure will need repeating. Here's a run-down of what needs doing and what can be skipped:


=== Prepare the schedule file ===

**This should already be done and can be skipped.** However, you can check for schedule and procedure files on the pcfs machines. For example, for Hobart there should be the following files on pcfshb for r4556:
<code>/usr2/sched/r4556hb.snp
/usr2/proc/r4556hb.prc</code>
> If they aren't there, follow the following steps to prepare them:
>  * [[operations:documentation.ivs.drudg_9.10.5|Preparing the schedule and procedure files]]
>  * On occasions, the Hobart data are written to disk between scans for e-transfer to Tsukuba for ultra-rapid EOP observations. Some additional changes to the schedule files are required in this case:
>    * [[operations:documentation.ivs.drudg_ureop_9.10.5|Additional schedule preparation for Hb ultra-rapid EOP experiments]]

=== Timing PC Software ===

This software should still be running from the previous experiment. **Skip.**

> For reference, here's a description of [[operations:documentation.ivs.timingsw|software on the timing PC]]

=== Field System Software ===

As you shouldn't have terminated the Field System, this should still be running. **Skip.** Again, for reference:
  * [[operations:starting_fs|Starting the PC Field System Software]]
  * [[operations:documentation:fs_antenna_9.10.5|Some notes on antenna control and monitoring]] using the new version of the Field system

=== System Monitor ===

Should still be running. **Skip.** 

>If you do need to re-start: [[operations:starting_sysmon|Start the System Monitor]]

=== e-Remote Ctrl ===

This should still be running too, but there are a few things to do here. 

>If for some reason you need to re-start eRemoteControl, here's how:
>  * [[operations:starting_eRemoteCtrl|Start e-Remote Ctrl]]
eRemoteControl will still be writing a local log file and pcfs_log_monitor will still be monitoring it. Although that log file has a name that doesn't match the new experiment, it's not essential to start a new local log (as it's only used locally and the master log on the pcfs is used at the correlator). 

> If you do want to start a new local log and monitor it, click on the red dot icon in econtrol to make the green bar go away: \\ {{:operations:econtrol_log_recording.png|}}. 
> Then [[operations:documentation.logmonitor_eremotectrl|set up the log monitor]] to provide warnings and alarms

To keep all log messages related to the new experiment in the same file, the next thing to do is
  * [[operations:eRemoteCtrl_newPCFSLog|Open a new PCFS log file]]
  * Now start the Checklist by loading the procedure file for the experiment, then ''exper_initi''. e.g for R1556 at Hobart: <code>proc=r1556hb
exper_initi</code>

The checklist should now be visible. The items in the list are described below and can be ticked off as you go, but many can be skipped in a follow-on experiment.

=== The Before Observation Checklist ===

The RF and IF signal paths, and DBBC are now configured through the Field System. 

== RF and IF signal path ==

Should already be setup and correct. **Skip.**

>For referenece here are notes on [[operations:rf_if_check_9.10.5|configuring the RF and IF signal paths]]

== DBBC Configuration ==

The DBBC should already be running and the PCFS should be able to communicate with it. 

>There should be no need to start any software on the DBBC but for reference here are the notes on setting up the DBBC:
>  * [[operations:documentation.DBBCSetupIVS_9.10.5|DBBC Setup]]

At the start of every scan, the pcfs executes the ''setupsx'' which sets the DBBC input channels, filters and BBC frequencies (and configues the Mark5). However, it's a good idea to execute it now so that a recorder test can be made:
  * For R1, R4, RD, RDV, T2, ANZ, CRDS, CRF, OHIG:<code>setupsx</code>
 
''setupsx'' calls ''ifdsx'' which sets up the DBBC Conditioning module inputs, filters and power levels, then ''dbbcsx8'' (or ''dbbcsx4'' for a 4 MHz DBBC mode)  which sets the BBC frequencies. Then if you type:
<code>iread</code>
You will see what the current Conditioning module settings are. Output format is:
<code><time>/<Module label>/<IF input number>,<Auto or Manual gain control>,<Nyquist filter number>,<Target power level>,<attenuation>,<actual power level></code>
Check there’s agreement with what appears in ifdsx. The actual power level should agree pretty well with the target level. The attenuation number can be anywhere between 0 (none) and 63 (maximum). If you see it at 0 or 63, it means the Conditioning module is having trouble getting the power to the right level. You may want to contact the on-call person in this case for help on getting the levels in range.

Then type:
<code>bread</code>
You will see what the DBBC has set the BBC freqs to (compare with the .prc file). Output looks like this:
<code><time>/<bbc name>/<Frequency (MHz)>/<Conditioning module in use>,<Bandwidth (MHz)>,...</code>
the Frequency, Conditioning module label and bandwidth should agree with the listing in ''dbbcsx8'' (or ''dbbcsx4''). 

== Check the maser ==
  * [[operations:maser_check|Hydrogen Maser check]]

== Mark5 Recorder setup ==
Next the Mark5 recorder needs to be prepared for the observations. 

If the allocated Mk5 module contains data:

Check the remaining space on the module and the compare with the space required for the experiment from the summary file. disk_pos can be used for such purpose. **Do NOT delete any data** unless it is something done as test recording.

If you need to swap disk modules:
  * Notes on [[operations:documentation.ivs.mark5_v2_swap_modules|swapping between Mark5 disk modules]]

Now check that the times are all OK:

<code>mk5=dot?</code>

look for ''syncerr_eq_0'', and that the final number is less than ~5 ms.
If you see something like ''syncerr_gt_3'' then ''fmset'' may need to be run to synchronise the clocks. To do this, open a terminal on pcfs[hb|ke|yg], and type
<code>fmset</code>
When the interface appears, type
<code>s</code>
then confirm with a 
<code>y</code>
Following this, the clocks should all be synchronised and agree with UT. Press the [Esc] key to exit ''fmset''. Then check the times again:

<code>mk5=dot?</code>

== Clock and delay check == 
  * [[operations:documentation.clock_and_delay_check|Checking clock offsets and delays]]

== Test recording ==
Test recording notes are given below. <note important>Note though that you should only test the module you'll be recording to (i.e. skip the last section where it describes how to test the second module), and //unless you are absolutely sure//, don't clear the disk module:</note>
  * [[operations:documentation.test_recording_fs9.10.5|Making a test recording]]

== System Temperature (Tsys) check ==
  * [[operations:documentation.test_tsys|Tsys measurement]] check

== Antenna checks ==

**Skip** these. 
>  * [[operations:documentation.test_antenna|Antenna checks]]

== Weather checks ==
  * [[operations:documentation.weather_check|Weather conditions]]

== Fringe check ==

**Skip** this unless you have at least an hour to spare!
  * [[operation:fringe_checking|Fringe checking procedure]]

== Send a Station Ready email ==
  * [[operations:documentation.station_ready_email|Sending a station ready email to IVS]]

== Skype ==
  * Start Skype and begin a chat session with all participating sites plus the on-call person


===== Starting =====

The usual startup procedure can now be done: [[operations:starting_monitoring_9.10.5|Starting and Monitoring]]