; CALRD
;---------------------------------------------------------------
;! Reads calibrator source model-image FITS file
;# TASK FITS CALIBRATION
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CALRD     LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC
CALRD:  Task to read in a calibrator FITS image file
OBJECT                             Object name
VLAOBS                             Code for arrays, band, or
                                   frequency
DATAIN                             To select Perley models from
                                   the web '2014', '2019'
OUTDISK           0.0       9.0    Disk drive # (0 => any)
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CALRD
Type: Task
Use:  CALRD loads an image of a calibration source from the standard
      AIPS area in which such FITS files are distributed.  It can also
      load from the Rick Perley's 2014 and 2019 model sets found on
      the web.  Use CALDIR to show you the available models.

      The Perley models are found on ftp.aoc.nrao.edu in directories
      pub/staff/rperley/MODELMAPS and pub/staff/rperley/MODELMAPS2019.
Adverbs:
  OBJECT.....The source name, e.g. 3C138
  VLAOBS.....The band code, e.g. K perhaps with array code e.g. AK
             although no array codes are used at present or frequency
             in GHz (for AIPS supplied models) or MHz for Perley models.
  DATAIN.....If DATAIN begins with 'PERLEY' and contains 2014 or 2019
             or is simply '2014' or '2019', then the available models
             listed are those found on the web in Rick Perley's 2014
             or 2019 model sets.
  OUTDISK....The disk drive #.  0 => highest with space
The input FITS file is INFILE='area:OBJECT_VLAOBS.MODEL' where area is
either AIPSTARS or FITS in that order.  The output image has
OUTNAME='OBJECT_VLAOBS'; OUTCL='MODEL'; OUTSE=0 (usually ends up 1).
Blanks are squeezed out so that there are no blanks preceeding the
underscore in the names.

Use CALDIR to determine what models exist.

Note, to use these as calibrators, you must enter a total flux in the
source table which is correct for your observing frequency.  Then
CALIB will scale the flux in these models to that total flux.

These models are in J2000 coordinates.  If your data are in B1950,
either change the uv data to J2000 with UVFIX or change the images to
B1950 with EPOSWTCH.

For the JVLA we are going to produce models at more closely spaced
frequencies.  One band so far has this done
  Name    BAND      actual frequency
  ----    ----      ----------------
   S       2.1         2.141 GHz
           2.7         2.663
           3.0         3.047
           3.5         3.463
           3.8         3.847
The Perley models have this done for other bands as well.
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