[evla-sw-discuss] VLA antennas and the EVLA parameters database

[Barry Clark]

The current code expects to find in the database:

antenna.WGCHAN  waveguide channel.  
    If not present or is zero, it expects
        station.FIBERDELAY
    If it is present, it expects
        station.WGDELAY (should have been WGLENGTH - sorry)
          setup.GROUPVEL<wgchannel>  (which it multiplies by the length)
          and there may be present setup.WG20<wgchannel> (extra length 20mm wg)

There may also be antenna.DELAY, added to that.
There are also antenna(band).DELAYA, antenna(band).DELAYB, antenna(band).DELAYC,
  antenna(band).DELAYD

This choice of parameters was a purely aesthetic excercise to get as 
little kludginess as possible dragged in by VLA antennas.  Didn't occur to
me until latter that I should have moved this stuff off into separate objects,
different for VLA and EVLA.