1.4 Examples

There are a number of example SCHED input files distributed with the program. They are in the examples subdirectory ($SCHED/examples if the environment variable is set on unix systems). Any can be consulted for information on how to run SCHED or for use as templates from which to create your own schedule. All should produce valid schedules if run as is. In fact, all are used in the Verify script that is used to check new installations and new versions of SCHED. All of the examples are described briefly and linked here. As of Dec. 2013, there were 52 examples. Some consolidation is on the agenda for future releases, partly from purging ones most appropriate for the legacy systems no longer in use.

The two examples in subsections below show a typical, reasonably simple, schedule and a minimal schedule of the type one might use for experiment planning. The latter is likely to be useful when writing proposals or doing other conceptual work.

Note that the example suite has grown up over many years and is in some considerable need up updating. All are valid schedules that run and could be used. But many features used are dated and new features and currently preferred styles are still only seen in a few. Some with recent (After late 2010) modifications that are especially current are manual_1.key, egdelzn.key, egrdbe.key, egrdbe2.key, egddc.key, and egcent.key which target certain new features, but also show decent scheduling style.

See the section of this manual on installation if SCHED is not yet installed on your computer and if your login is not set up to run SCHED. Also see the Running SCHED section for instructions on how to start the program.

If your version of SCHED is linked with the PGPLOT libraries (has plotting capability) and you are on a unix system, you will need to set the environment variables PGPLOT_DIR to the location of the PGPLOT libraries and PGPLOT_FONT to the location of the PGPLOT font files, if that is not the same as PGPLOT_DIR.

manual_2.key
This file is shown below as the first example. It is a fairly typical SCHED input file for a VLBA plus the GBT observation. It uses defaults where it can and is relatively simple. This example is a good file to use as a template for making new schedules. This file has not been updated from MARK5A to MARK5C.
manual_1.key
This file will produce the same schedule as the first example. However, for demonstration purposes, far more parameters are actually specified in the input file. This includes having at least parts of all auxiliary input files (catalogs etc) imbedded. It is fairly complicated and contains a lot of comments in an attempt to show many SCHED features and give some advice on scheduling strategy. It has been updated to use the RDBE/DDC system on the VLBA and the WIDAR on the VLA.
manual_simp.key
is the second example below. It is a very simple file that can be used to make plots for experiment planning purposes. Because of the lack of cover information and because of the special optimization mode used, it cannot be used to produce telescope control files.
egplan.key
is much like [manual_simp.key]. It is a simple schedule to assist in experiment planning. It is a bit more complete than manual_simp.key.
eglst.key
is a sample schedule using LST in the way requested for dynamic scheduling projects on the VLBA.
egvlba.key
is a sample schedule for VLBA observations. It demonstrates band switching and some recording control procedures not in manual_2.key. It also demonstrates providing PREEMPT=EXTRA scans on the ends of the project so that operations might be able to provide extra data if there is a gap that cannot otherwise be filled between projects.
eg24.key
is a sample schedule of a simple project on the VLBA, but one that goes for 24 hours. For dynamic scheduling, it is useful to be able to wrap such schedules to use a different start time. This shows how to put in comments for the schedulers to aid that process and shows how the schedulers can use parameters WRAP24 and DOSCANS to simplify the wrapping process. Note, this has not yet been updated from MARK5A to MARK5C.
egOH.key
is a sample spectral line file for VLBA observations of several OH masers transitions.
egcent.key
is a sample showing how to specify multiple phase centers for a pointing center for the DiFX correlator.
egdelzn.key
demonstrates how to use the capability in SCHED to add automatically short geodetic segments for the purpose of atmospheric calibration delay. Note that similar segments, with very short scans, can be added for tropospheric opacity calibration. This example also shows the use of the PREEMPT parameter to protect specific scans from preemption at Pie Town and Mauna Kea for daily EOP observations of up to 1.5 hr.
dqhiel.key
demonstrates how to use the HIGHEL optimization mode which can pick the scan with the highest elevations across the array from among a group of suggested scans. It is useful for testing but also can be useful for picking fringe finders etc. This schedule is based on the regular data quality tests.
egrdbe2.key
demonstrates a SCHED file for use with the new digital backend and Mark5C recorders being deployed on the VLBA and elsewhere. This one is relatively simple and uses the PFB personality which gives many channels of fixed frequency and bandwidth. It does exercise the mode where one station (GBT) has to observe in the opposite sideband from others.
rdbepfb.key
is a stripped down version of egrdbe2.key that shows a rather basic schedule for the VLBA only using the RDBE with the PFB personality. It uses a SCHED standard setup so the user doesn’t need to set the configuration information.
egcwide.key
Example sched input for a VLBA using the RDBE with the PFB personality and the wideband 6 cm receiver. Setups are given that use dual polarization in one pair of IFs and that use single polarization in two IFs at very different frequencies.
egddc.key
demonstrates a SCHED file for use with the new digital backend and Mark5C recorders being deployed on the VLBA and elsewhere. This one allows flexible baseband frequencies and bandwidths, but provides fewer channels than the PFB personality.
egddc2.key
demonstrates a SCHED file for use with 2 RDBE’s and 8 channels from the DDC personality. Otherwise it is a fairly simple VLBA schedule. The deployment of 2 RDBE’s is expected in early 2013.
manual_line.key
is the example that is included in the spectral line section of this manual. It is for VLBA and GBT observations of 7mm SiO lines. It is more complicated than egOH.key and also demonstrates setting GBT frequencies and many other setup parameters that were defaulted in egOH.key. This file has not been updated from MARK5A to MARK5C.
eg512.key
is a sample schedule for the VLBA that uses the 512 Mbps mode.
eg512g.key
is a sample schedule for the a global observation that uses 512 Mbps with the RDBE.
eg1024.key
is a sample schedule for the EVN that uses the 1024 Mbps mode with DBBC, VLBA4, and MKIV systems.
eg2head.key
is a sample schedule for an EVN observation that uses the 512 Mbps mode. This uses 2 heads on one tape drive on Mark IV stations. VLBA4 and DBBC stations are included. Note that it is possible to do 512 Mbps on the VLBA and Mark IV stations simultaneously. The VLBA uses 2 drives while the Mark IV systems use 2 heads. This is actually based on a network monitoring observation.
egglobal.key
is a sample file for simple continuum observations involving the VLBA, the EVN,and the GBT. The VLA has been removed because this example uses the legacy recording system which is no longer supported at the VLA. This file has not been updated from MARK5A to MARK5C.
egglobalOH.key
is a sample file for line observations involving the VLBA, the EVN,and the GBT.
egvsop.key
is a sample schedule for Mark IV / VLBA observations specifically using modes appropriate for observations with the Japanese VLBI satellite, VSOP. It will produce VEX format schedules for stations that use the field system and VLBA format files for those stations that need them. VSOP (HALCA) is no longer operational, but the VSOP-2 project has started so this example has been retained. It will be modified for VSOP-2 when that project is far enough along to make it clear what is needed. This file has not been updated from MARK5A to MARK5C.
eg3mma.key
is a VLBA schedule for observations at 86 GHz. There is special emphasis on reference pointing, which is done explicitly in this file. This file uses the RDBE_DDC at 2 Gbps using 8 channels of 64 MHz each.
eg3mmb.key
is another 2Gbps VLBA schedule for observations at 86 GHz. There is special emphasis on reference pointing, which is done automatically in this file based on information in the peak.cmd file.
eg3mmc.key
is yet a third VLBA 3mm schedule, again using automatic insertion of pointing scans. But this time, the file with the commands controlling that insertion is inserted in the main schedule file and is somewhat simplified from that in eg3mmb.key This file does not create the separate new and old system files needed for reference pointing on masers while observing with the new RDBE wide band system with the PFB personality. For instructions on how to do that, please see eg3mm_rd2.key. This file has not been updated from MARK5A to MARK5C.
eg3mm_rd2.key
is similar to eg3mmb.key, but shows how to make reference pointing observations, when using the RDBE wide band system with the PFB personality which uses fixed 32 MHz channels and cannot be fine tuned. It uses the crd parameters to specify the allowed bandwidth and frequency, including using Doppler calculations, to set the legacy system as desired.
vips11.key
shows use of OPTMODE=HAS for automatic scheduling. This mode tries to obtain a requested number of scans on each source and spread them reasonably evenly over the time available. It pays some attention to minimizing slew times. It is meant to simplify scheduling of projects that try to image a number, perhaps large, of sources using multiple snap-shots on each. It was originally provided for the VIPS project but should be useful for many other programs.
evn_cont_strong.key
is an example of EVN observations at 18cm. The observing pattern is an 11 minute cycle with 2 minutes on a calibrator and 9 minutes on a target source. This observation is at 128 Mbps.
evn_cont_strong_pol.key
is essentially the same schedule as evn_cont_strong.key, but with a D term calibrator and a polarization position angle calibrator added.
evn_cont_weak_256.key
is phase referencing schedule for the EVN with a 5 minute cycle time using 256 Mbps.
evn_cont_weak_512.key
is a similar phase referencing schedule for the EVN, but uses 512 Mbps which requires 2 headstacks.
evn_cont_weak_snap.key
is an EVN schedule for 256 Mbps observations of multiple snapshots using phase referencing.
evn_line_hi.key
is for EVN observations of an extragalactic 21-cm HI source.
evn_line_meth.key
is for EVN only observations of the 6.7 GHz line of methanol in a galactic source.
eg5cm.key
is a sample schedule for the EVN and EVLA that observes near 6.7 GHz. It is the same as evn_line_meth.key, but with the EVLA added.
egmk5vex.key
is for EVN only observations using the Mark5 system. It is based on a Network Monitoring schedule. Note that it is a bit dated in that it uses the Mark5A system for a VLBA station which no longer has that option.
hsa1cm.key
is a sample schedule for the High Sensitivity Array (HSA - VLBA + GBT + Effelsberg) at 1cm. This file does not include the VLA and Arecibo.
hsa21cm.key
is a sample schedule for the High Sensitivity Array (HSA = VLBA + GBT + Effelsberg + Arecibo (VLA removed)) at 21cm. The schedule uses the legacy system which is not available at the VLA so the VLA has been taken out for now.
hsaddc.key
is a rather complex example that uses the RDBE with the DDC personality on the VLBA, VLA, GBT, and Effelsberg. There are segments at 6cm, 1cm, and 3mm. It exercises array phasing at the VLA, reference pointing at all of the telescopes, and Doppler tracking.
lba.key
is a sample schedule for the Long Baseline Array in Australia.
lba_h20.key
is a sample schedule for the Long Baseline Array in Australia using LBA DAS/Recorder only. Observations are at the 22 GHz water line.
lba_oh.key
is a sample schedule for the Long Baseline Array in Australia using LBA DAS/Recorder only. Observations are at the 1.8 GHz OH line.
lba_mk5.key
is a sample schedule for the Long Baseline Array in Australia when some MARK5 stations are included.
planvla.key
is a planning file similar to the other VLBA planning files, but has all 27 stations of the VLA A configuration. You can use this to explore VLA uv coverage etc. It should still work despite the current (2014) inability to schedule the VLA for other than VLBI. It doesn’t actually create observing files.
doptg.com
is a script that creates and runs VLBA pointing observations. It exercises one of the optimization modes to allow the same script to be used for any time slot for any time of year. This example will not be run by the Verify script if the site is not at NRAO because the ephemeris routines used for pointing at planets will not generally be available. It is also not of much interest beyond the staff responsible for maintaining the VLBA.
doptg2.com
is a script that creates and runs VLBA pointing observations. It is very much like doptg.com except that it uses the DOSTA parameter to allow the same script to be used for stations with 3mm and stations without 3mm.
egsat.key
demonstrates scheduling a satellite observation using both MER-B and Stardust. It also includes Mars to exercise the planet option. These capabilities are unlikely to be of interest outside of the AOC. In fact, the required NAIF software libraries would hugely increase the size of the SCHED distribution and are not normally included. This file has not been updated from MARK5A to MARK5C.
dq415.key
is a data quality test file from early 2014 that uses the RDBE and MARK5C. It samples most of the RF bands available on the VLBA.
mt506.key
is one of the weekly VLBA integrity check observations from the MARK5A era. It is here mainly to exercise SCHED in a mode that uses lots of setup files. It is similar to the more modern dq415.key but uses the outdated recording system. It should probably be removed soon.
jvla.key
is an example covering use of the VLA as a phased array for VLBI. This version uses the 32 MHz output baseband bandwidths of the WIDAR to create recordings that can be played against 4 of the 16 channels created by the PFB personality of the RDBE on the VLBA.
n2227.key
is a sample USNO Earth Orientation observation using PT and MK.
pfbsettst.key
is a vehicle for testing all the new RDBE/MARK5C standard setup files that use the pfb personality. These are the setups that start with rdbe_pfb.
egsat.key
is a sample VLBA observation of spacecraft with bsp ephemeris files. Note that the satellite tracking in SCHED uses the NAIF software from JPL. The object libraries for linux g77 and gfortran are included with SCHED, but may not be usable on all machines. The code is not exported. Normally, other than in the AOC, the stub routines are used and SCHED cannot deal with satellites. Also, SCHED does not have a way to pass the necessary site dependent, moving source positions to non-VLBA stations.
tlesat.key
is a sample VLBA observation of spacecraft using TLE ephemeris files. See the note above (egsat.key) about the satellite tracking software. It applies here too.
newsyn.key
is a VLBA test observation to check the performance of the new front end synthesizers being designed in 2013-2015. Those synthesizers have finer tuning steps than the current ones (10kHz vs 200 or 300 MHz). They are not yet deployed except at a couple of sites so this example is not yet of interest to users.
tstsets.key
is a VLBA test observation that tests the standard setups used with the RDBE/DDC. Only bit rates under 512 Mbps are tested. This is not a maintenance schedule, not one users would likely want to emulate.
piggyback.key
is a VLBA test observation that observes with both the Mark5A and Mark5C systems. As of early 2015, only two VLBA stations even have Mark5A so this is only of interest to VLBA testers.

1.4.1 A Basic VLBA Schedule.

The following example gives a fairly typical schedule that relies on SCHED’s defaulting schemes and standard catalogs to get most of the required information. The cover and correlator information cannot be reduced nor can the individual scan information. All of those inputs are unique to the observation. This example is probably the most useful one for users to use as a template for making their own VLBA schedules, including for observations that include the VLA. It used to produce the same schedule as manual_1.key but that example actually shows how many items, that are defaulted or taken from standard catalogs here, can be specified in the schedule file. More recently (late 2012), manual_1.key was converted to use the wideband RDBE system. Note that manual_2.key has not yet been updated from MARK5A to MARK5C.

!  BE002 example of 3C84 observations at 6 and 4 cm.  
!  
!    This example used to produce the same schedule as manual_1.key  
!    but uses many SCHED defaults and is missing most comments.  
!    It shows approximately the sort of file a users would  
!    normally make.  Note that all catalogs are defaulted.  
!  
!    On Nov. 1, 2012, this example was modified to use the GBT  
!    rather than the VLA which can no longer do legacy style  
!    observations.  Eventually it, like manual_2.key, will be  
!    moved to the new wide band systems.  
!  
overwrit  
! ==========================================================  
! =================  Cover Information  ====================  
! ==========================================================  
 
version  = 1  
expt     = ’Example: 3C84 6, and 4 cm’  
expcode  = BE002  
obstype  = VLBA  
 
piname   = ’Craig Walker’  
address1 = ’National Radio Astronomy Observatory’  
address2 = ’P. O. Box O’  
address3 = ’Socorro, New Mexico, 87801’  
address4 = ’ U.S.A. ’  
phone    = ’505 835 7247 ’  
obsphone = ’505 835 7247 ’  
email    = ’cwalker@nrao.edu’  
fax      = ’505 835 7027 ’  
obsmode  = ’Continuum’  
correl   = ’Socorro’  
note1    = ’ ’  
 
! ==========================================================  
! ==============  Correlator Information  ==================  
! ==========================================================  
 
correl   = ’Socorro’  
coravg   = 4  
corchan  = 16  
cornant  = 10  
corpol   = ’on’  
corwtfn  = ’uniform’  
corsrcs  = ’SCHED’  
cortape  = FTP  
corship1 = ’Craig Walker’  
corship2 = ’P. O. Box O’  
corship3 = ’Socorro NM 87801’  
cornote1 = ’ ’  
!  
 
! ==========================================================  
! ======= Standard Source and Station Catalogs  ============  
! ==========================================================  
! Standard source catalogs are sources.gsfc and sources.rfc.  
! This schedule uses some aliases only in sources.gsfc.  
srcfile  = $SCHED/catalogs/sources.gsfc  
stafile  = $SCHED/catalogs/stations.dat  
freqfile = $SCHED/catalogs/freq.dat  
 
 
! ==========================================================  
! ==================== Setup Information ===================  
! ==========================================================  
!  The first setup file shows the bare minimum that needs to  
!  be specified.  Essentially all of this information would  
!  be needed to choose one of the standard setup files.  This  
!  one would correspond to v6cm-64-4-1.set, with a possible  
!  slight frequency offset between what is in the specific  
!  "standard setups" and what is generated using BAND=6cm.  
 
setinit = v6cm.set /  
   nchan    = 4  
   band     = ’6cm’  
   bbfilter = 8.0  
   bits     = 1  
   pol      = dual  
   /  
endset /  
 
!  For the second example setup, the user forces the  
!  frequencies, BBC’s, sidebands, and format.  It still  
!  relies on the frequency catalog for the IF assignments  
!  and for many VLA parameters.  There are a lot more  
!  parameters that could be forced in extreme cases.  
 
setinit = v4cm.set /  
   nchan    = 4  
   freqref  = 8416.99  
   freqoff  = -3.5, -3.5, 4.5, 4.5  
   bbfilter = 8.0  
   bits     = 1  
   bbc      = 1,    2,    3,   4  
   netside  = U,    U,    U,   U  
   pol      = RCP,  LCP,  RCP, LCP  
   format   = VLBA1:4  
   /  
endset /  
 
! ==========================================================  
! ========================  The Scans  =====================  
! ==========================================================  
year  = 1995  
month = 10  
day   = 22  
start = 01:30:00  
 
!  Note use of station codes.  Names could also be used.  
stations = SC, HN, NL, FD, LA, PT, KP, OV, BR, MK, GBT_VLBA  
 
Source = 3C454.3   Dur   = 5:30   Setup = v6cm.set    /  
Source = 3C454.3   Dwell = 5:30   Setup = v4cm.set /  
 
stations = SC, HN, NL, FD, LA, PT, KP, OV, BR, GBT_VLBA  
 
group 4 rep 14  ! About 3 hours in 12 repeats of the next 4 scans.  
Source = 3C84      Dur   = 3:00  gap = 2:00  Setup = v6cm.set /  
Source = 3C84      Dwell = 3:00  gap = 0     Setup = v4cm.set /  
Source = 0309+411  Dwell = 2:00  /  
Source = 3C84      Dwell = 3:00  /  
 
!  Add MK  
stations = SC, HN, NL, FD, LA, PT, KP, OV, BR, MK, GBT_VLBA  
 
group 4 rep 14  !   About 3 hours.  
Source = 3C84      Dur   = 3:00  gap = 2:00  Setup = v6cm.set /  
Source = 3C84      Dwell = 3:00  gap = 0     Setup = v4cm.set /  
Source = 0309+411  Dwell = 2:00  /  
Source = 3C84      Dwell = 3:00  /  
 
group 8 rep 15  !  6.5 hours  
Source = 3C84      Dur   = 3:00  gap = 2:00  Setup = v6cm.set /  
Source = 0552+398  Dwell = 3:00  gap = 0     /  
Source = 0552+398  Dwell = 2:00  gap = 0     Setup = v4cm.set /  
Source = 3C84      Dwell = 3:00  gap = 0     /  
 
Source = 3C84      Dur   = 3:00  gap = 2:00  Setup = v6cm.set /  
Source = 3C84      Dwell = 3:00  gap = 0     Setup = v4cm.set /  
Source = 0309+411  Dwell = 2:00  /  
Source = 3C84      Dwell = 3:00  /  
 
Source = 3C273     Dur   = 5:30  gap = 3:00  Setup = v6cm.set /  
Source = 3C273     Dwell = 5:30  gap = 0:00  Setup = v4cm.set /  
 
! ==========================================================  
! ========================  End of example  ================  
! ==========================================================

1.4.2 A Minimal Schedule for Planning.

SCHED input files can be simple for simple situations. The following file is about as simple as a SCHED file can get. It is set up for exploring the u-v and sky coverage, and times of availability, of a list of sources using the plotting abilities of SCHED and using the UPTIME optimization mode to give overlapping 24 hour schedules for each source.

!----------------------------------------------------------------------  
!  Example of very simple SCHED file - for making uv etc plots.  
!----------------------------------------------------------------------  
overwrit                 !  Allow writing over old output files.  
expcode  = UVCOV         !  Needed for name of summary file.  
obstype  = NONE          !  No tape recording.  
nosetup                  !  No setup file.  
optmode  = uptime        !  Planning mode.  
opdur    = 24:00:00      !  Look at a whole day.  
opminant = 4             !  Minimum number of antennas that must be up.  
opminel  = 15            !  Don’t include scans below this elevation.  
year     = 1996  day = 1 !  Year and day.  
start    = 00:00:00      !  Start time for plots.  
dur      = 10:00         !  Ten minute scans.  
stations = SC, HN, NL, FD, LA, PT, KP, OV, BR, MK  
source   = DA193 /  
source   = 3C120 /  
!----------------------------------------------------------------------  
! End of example.  
!----------------------------------------------------------------------

If the above file were named uvcov.key, it could be run with the commands:

sched  
plot sch=uvcov.key /

When the plot section is reached, a graphical interface will appear that is reasonably obvious how to use.