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Pulsar observing with Astrid scripts -- advice for multiple backends

-- in which we give example configurations for various multiple backends.

(Warning: these combinations will not work if you are using multi-beam receivers, ie 12 GHz or above.)

Handy functions

Usage:

• if you want the band center for BCPM, CGSR2, or GASP to be different than the value of "restfreq" as given to the configuration, then you need to run "psrset" after running the configuration.
• All frequencies are in MHz. You can leave out any arguments that you are not using.
• bcpm_freq is the desired center frequency for the BCPM.
• cgsra_freq is the desired center frequency for bank A of the CGSR2.
• cgsrb_freq is the desired center frequency for bank B of the CGSR2.
• gasp_freq is the desired center frequency for GASP.

setnoise( noiseval, receivername)

• noiseval is "off", "lo-ext", or "hi-ext"
• receivername is one of the standard receiver names.
• this function just enables or disables the noise cals in the receiver. It does not change the switching rate or type of switching.
• the receiver names are: "Rcvr_342", "Rcvr_450", "Rcvr_600", "Rcvr_800", "Rcvr_1070", "Rcvr1_2", "Rcvr2_3", "Rcvr4_6", "Rcvr8_10", "Rcvr12_18", "Rcvr18_22", "Rcvr22_26", "Rcvr26_40", "Rcvr40_52"
• this is only useful if you have set "swmode=tp" in the configuration. --- if you set "swmode=tp_nocal", then the cals are off and setnoise has no effect.

SPIGOT/BCPM/GASP

Notes:
If one wants the center of the band to be the same sky frequency for all three backends, then there is no need to use the "psrset" function.
If the center frequencies are different, then one may use the function "psrset", as shown in this example.

• In this example:
• the Spigot receives a 50 MHz band centered at 1390 MHz
• the BCPM receives an 80 MHz band centered at 1400 MHz
• the GASP receives an 80 MHz band centered at 1410 MHz

Note that you also have to set the BCPM frequency into the BCPM manager with "SetValues(BCPM...)" as shown below for the BCPM search scan.

Astrid configuration script

#----------------------------------------------------------------
# revised Astrid configuration script for Ingrid's SPIGOT/BCPM/GASP case.

# just for instance source catalog -- replace with your objects.
Catalog(pulsars_brightest_GBT)

# Import cal-control and multi-backend config scripts
execfile("/users/gbpulsar/python/psrset.py")

# Setup the system for SPIGOT/BCPM/GASP
con1 ="""
receiver  = 'Rcvr1_2'
restfreq =  1390.0      # this will be the center sky frequency for the Spigot
beam      = 'B1'
pol       = 'Linear'
obstype   = 'Spectroscopy'
backend   = 'SPIGOT/BCPM/GASP'
nwin      = 1
deltafreq = 0
bandwidth = 50
swmode    = "tp"
swtype    = "none"
swper     = 0.04
swfreq    = 0.0, 0.0
tint      = 5
vlow      = 0
vhigh     = 0
vframe    = "topo"
vdef      = "Radio"
noisecal  =  "lo"
nchan = 'medium'
#
# ACS settings
spect.levels = 3
spect.numbanks = 2
#
# BCPM settings
bcpm.ch_bw = 0.5
bcpm.sample_time = 'X2'
bcpm.sum_pol = 'Yes'
bcpm.submanager = 'bcpm2'
bcpm.source_name = 'test'
bcpm.hardware = 'bcpm1'
"""

#-----Remember to first start the BCPM control screens,
#  then cycle the BCPM manager -- do this before running the Configuration!
SetValues("BCPM", {"state": "Off"})
Break("Check that BCPM has finished shutting down.")

SetValues("BCPM", {"state": "On"})
Break("Check that BCPM has finished initializing")

#-----now run the configuration.
Configure(con1)

#---this just illustrates the setnoise function
setnoise("off", 'Rcvr1_2' )
Break("Check that the cals are OFF in the receiver now.", None)

setnoise("lo-ext", 'Rcvr1_2' )
Break("Check that the cals are ON in the receiver now.", None)

#------put the Spectrometer into the scan coordinator so that we can balance
SetValues("ScanCoordinator", {"subsystemSelect,Spectrometer":1} )

#------remove the DCR from the scan coordinator so it is not driven crazy
SetValues("ScanCoordinator", {"subsystemSelect,DCR":0} )

# IF sky frequency for Spigot, BCPM, and GASP are all the same,
# no more is needed.
# if not, then if BCPM center freq = 1400 and GASP will be 1410,
# then do the following:

psrset('Rcvr1_2', bcpm=1400, gasp=1410)

# Move to test pulsar
Slew("B1937+21")

Balance()
Balance("Spectrometer")
Break("Check that spectrometer is balanced")

#-----remove Spectrometer and turn off before proceeding with Spigot setup
SetValues("ScanCoordinator", {"subsystemSelect,Spectrometer":0} )
SetValues("Spectrometer", {"state": "Off"})
#----------------------------------------------------------------
#----------------------------------------------------------------

Astrid script for running the BCPM in monitor mode

#------------------------------------------
# block to run the BCPM in monitor mode
Catalog(pulsars_brightest_GBT)

# designate test pulsar
src = "B1937+21"

SetValues("BCPM", {"target_name" : src} )
SetValues("BCPM", {"base_name" : src } )
SetValues("BCPM", {"operating_mode" : "monitor"} )
Slew(src)
Balance()

Comment("Tracking source -- run setpower")
Track(src, None, 300)
#--------------------------------------------
#--------------------------------------------

# block to run the BCPM in search mode
execfile("/users/gbpulsar/python/psrset.py")
Catalog(pulsars_brightest_GBT)

# designate test pulsar
src = "B1937+21"

SetValues("BCPM", {"target_name" : src} )
SetValues("BCPM", {"base_name" : src} )
SetValues("BCPM", {"data_storage" : "Tape"} )
SetValues("BCPM", {"file_size" : 720} )

# note : desired center sky frequency should agree with what you set with psrset.
SetValues("BCPM", {"center_frequency,2" : 1400} )

SetValues("BCPM", {"operating_mode" : "search"} )

setnoise("off", 'Rcvr1_2' )   # turn off noise cals (if desired)

Comment("Tracking source -- one minute scan ")
Track(src, None, 60)
#------------------------------------------------
#------------------------------------------------

BCPM/CGSR2

• This example shows the case in which the two banks of the CGSR2 receive two different sky frequency bands.
• If you want the BCPM sky frequency to be the first of the two restfreqs, then there is no need to run "psrset"
• In this example:
• Bank A of the CGSR2 receives a band centered at 1373 MHz
• Bank B of the CGSR2 receives a band centered at 1433 MHz
• the BCPM receives a band centered at 1400 MHz

-------------------------------------------------------------------
#-------Example for BCPM and CGSR2 setups
#
#-------load the psrset and setnoise functions
execfile("/users/gbpulsar/python/psrset.py")

configure = """
receiver  = 'Rcvr1_2'
restfreq = 1373.0, 1433.0
obstype   = 'Pulsar'
backend   = 'BCPM/CGSR2'
pol       = 'Circular'
#swmode    = "tp"
swmode    = "tp_nocal"
swtype    = "none"
swper     = 0.04
swfreq    = 0.0, 0.0
nwin      = 2
deltafreq = 0,0
bandwidth = 190   # do not set to 200 when using CGSR2 !!
tint      = 5
vlow      = 0
vhigh     = 0
vframe    = "topo"
vdef      = "Radio"
noisecal  =  "lo"
nchan = 'low'
# BCPM specific
bcpm.ch_bw = 1.0
bcpm.sample_time = 'X2'
bcpm.sum_pol = 'Yes'
bcpm.submanager = 'bcpm2'
bcpm.source_name = 'test'
bcpm.hardware = 'bcpm1'
"""

#-----Remember to first start the BCPM control screens,
#  then cycle the BCPM manager -- do this before running the Configuration!

SetValues("BCPM", {"state":"off"})
Break("Wait until BCPM power-down sequence is complete!")

SetValues("BCPM", {"state":"on"})
Break("Wait until BCPM initialize sequence is complete!")

Configure(configure)


# in this example, set the sky freq for the BCPM to 1400 MHz
#
psrset("Rcvr1_2", bcpm=1400)

Balance()
Break("Check Balance")
#
# ----note that this balance just adjusts levels in the IF Rack.
# the user must set power levels for the CGSR2 by hand,
# by adjusting attenuators in Converter Modules 9,13,10,14.

# ------- remove DCR from scan coordinator
SetValues("ScanCoordinator", {"subsystemSelect,DCR":0} )
------------------------------------------------------------

SPIGOT/BCPM/CGSR2

• In this case, you have to use the "psrset" command, giving values at least for cgrsa and cgsrb, otherwise the CGSR2 will not be properly connected.

• In this example:
• the Spigot receives a 200 MHz band centered at 1410 MHz
• CGSR2 bank A receives a band centered at 1373 MHz
• CGSR2 bank B receives a band centered at 1433 MHz
• the BCPM receives a band centered at 1400 MHz

---------------------------------------------------------------
# Example for SPIGOT, BCPM, and CGSR2 setups
#
# load the psrset and setnoise functions
execfile("/users/gbpulsar/python/psrset.py")

configure = """
receiver  = 'Rcvr1_2'
restfreq  = 1410
obstype   = 'Spectroscopy'
backend   = 'SPIGOT/BCPM/CGSR2'
pol       = 'Circular'
swmode    = "tp_nocal"
swtype    = "none"
swper     = 0.04
swfreq    = 0.0, 0.0
nwin      = 1         # note nwin must be 1 when using the Spigot.
deltafreq = 0,0
bandwidth = 200
tint      = 5
vlow      = 0
vhigh     = 0
vframe    = "topo"
vdef      = "Radio"
noisecal  =  "lo"
nchan = 'low'
#
# spectrometer
spect.levels=3
#
# BCPM specific
bcpm.ch_bw = 1.0
bcpm.sample_time = 'X2'
bcpm.sum_pol = 'Yes'
bcpm.submanager = 'bcpm2'
bcpm.source_name = 'test'
bcpm.hardware = 'bcpm1'
"""

# ------FIRST cycle BCPM off and on, Then do the config
SetValues("BCPM", {"state":"off"})
Break("Wait until BCPM power-down sequence is complete!")

SetValues("BCPM", {"state":"on"})
Break("Wait until BCPM initialize sequence is complete!")

Configure(configure)

# put Spectrometer into scan coordinator so we can balance
SetValues("ScanCoordinator", {"subsystemSelect,Spectrometer":1} )

# tweak for BCPM and CGSR2
# in this example, set the sky freq for the BCPM to 1400 MHz
#
psrset("Rcvr1_2", cgsra=1373, cgsrb=1433, bcpm=1400)

Balance()
Balance("Spectrometer")
Break("Check Balance")
#
# note that this balance just adjusts levels in the IF Rack.
# the user must set power levels for the CGSR2 by
# adjusting attenuators in Converter Modules 9,13,10,14.
# note that the attenuators in the Converter rack must
# be set by hand


# remove Spectrometer from scan coordinator
SetValues("ScanCoordinator", {"subsystemSelect,Spectrometer":0} )


# remove DCR from scan coordinator
SetValues("ScanCoordinator", {"subsystemSelect,DCR":0} )
---------------------------------------------------------------

-- FrankGhigo - 28 Feb 2006