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TUNING

        [NOEMAOFFLINE\]TUNING  [Ftune(GHz)  Sideband  FIF(MHz)]  [/ZOOM Key-
    word] [/PAGEWIDTH] [/INFO] [/FIXED_FREQ]

    Without arguments, the command displays the available bands of NOEMA Re-
    ceivers.   With the option /INFO several informations about the receiver
    are displayed in the terminal.

    Different ranges are colorized:
    Black           : outside the receiver bands
    Dark grey       : in the receiver bands, but not accessible with the present
    White           : in the receiver bands, accessible with the present tuning

    With arguments, the command defines the tuning of one of  the  band  and
    represents it on the global view.

    Tuning syntax:
    Ftune   : Frequency to tune (in GHz)
    SideBand: Sideband where to place Ftune (LSB or USB)
    FIF     : Position where Ftune will be placed in the IF band (in MHz)

    Ftune  must  be in the current frequency main axis (REST by default, but
    can be changed with SET FREQUENCY command)

    If a source has been defined, its velocity (or redshift) is  taken  into
    account to convert Ftune to RF frequency.

    NOEMA  observations  are preferentially performed using a limited number
    of LO frequencies for which receiver performances have  been  optimized.
    Those  frequencies  are  distributed  all  over the receiver bands every
    500MHz (the so-called  tuning  grid).  The  NOEMAOFFLINE\TUNING  command
    takes  this  into  account  and  shifts  the  IF center frequency FIF if
    necesssary so that the LO tuning frequency matches the tuning grid.

    The tuning frequency is computed using only  the  source  LSR  velocity.
    With  the Doppler tracking, the actual LO is slightly different from the
    tuning frequency.  Both tuned and tracked LO frequencies  are  given  in
    output.   With  the  option  /FIXED_FREQ, the command ignores the tuning
    grid.


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Gildas manager 2018-11-17