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Example Observations (Currently only HBA)

Combining everything found in this chapter, we can provide an example observation. This code block describes initialisation of the station, beamforms using a selected set of RCUs on the I-LOFAR default subbands, then shuts down the station when the observation is complete. Overallwe generally use

  • A swlevel command to enter level 2,
  • A pre-amble block to configure the RSPs to required bitmodes and other states,
  • A swlevel command to enter level 3,
  • A (or multiple) beamctl commands to perform a block of observations, each of which is manually killed after a specified beam length (beamctl does have a duration flag, but the process does not exit after the beam expires)
  • A command to return the station to swlevel 0 for the next user
# Observation starting 2021-07-14T06:57, recording to beign at 2021-07-14T07:00
# 2021-07-14T07:00 - 2021-07-14T07:29 :	J0139+3310 [0.43613087285590374, 0.5867200623795394, 'J2000']

bash ./sleepuntil.sh 20210714 065700
echo 'Initialising: SWLEVEL 2' 
eval swlevel 2 

# Using a preamble that has been passed down through the ages.
# I honestly cannot tell you the benefits / downsides of most of these rspctl commands.
rspctl --wg=0 
sleep 1 
rspctl --rcuprsg=0 
sleep 1 

# Swap to 8-bit mode to allow for use of the full bandwidth
rspctl --bitmode=8 
sleep 1 
killall beamctl 
sleep 3 
echo 'Initialising: SWLEVEL 3' 
eval swlevel 3 
sleep 2 

# Ensure the SEREDES splitter is disabled and datastream is on (should not be needed, just encase
rspctl --splitter=0 
sleep 1
rspctl --datastream=1
sleep 3 


rcus='0:83,86:159,162:191' 
pointing='0.43613087285590374,0.5867200623795394,J2000'
beamctl --antennaset=HBA_JOINED --rcus=$rcus --band=110_190  --beamlets=0:487 --subbands=12:499 --anadir=$pointing --digdir=$pointing &
bash sleepuntil.sh 20210714 072910
killall -9 beamctl

swlevel 0
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