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Subreflector

Again, there would be a database of the subreflector model parameters, containing for each antenna and receiver, the required focus setting, focus vs sin(elevation) coefficient, focus vs temperature coefficient, x,y focus position, x vs cos(elevation) coefficient. Again, quantities in the script are added to those in the database.

focus = <focus offset in mm>

xfocus = <x direction translation in mm>

yfocus = <y direction translation in mm>

temperature = <temperature, C>
   ! if temperature is 0, use on-line outside thermometer

calibration = <ON | OFF | SWITCHING>
   ! Subreflector center calibration device
   ! As I understand it, calibration scheme still undecided.
   ! Might require a few more codes (ie thermal calib might need ONHOT, ONCOOL)

! parameters need to be added for control of nutating subreflector if one
! is eventually decided on; I understand one is not in the baseline plan.



Kate Weatherall
2000-03-08