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        CLIC\MODIFY BUG number

    This  command  is  reserved for the correction of nasty bugs in the data
    acquisition.  The number is used for identification.

    Current accepted values:

      1 Affecting data taken between 11-nov-1995 and  09-jan-1996.   Bug  in
        RDI  found by S.Guilloteau. The continuum data was erroneously cali-
        brated in the real-time aquisition. As result,  the  continuum  data
        did  not  agree with the average of the spectral data.  For instance
        plotting data with "set sub C02 L02" as a  function  of  time  gives
        different  results for C02 and L02. The result would affect line in-
        tensities if, as is usually the case, the amplitude  calibration  is
        done with the continuum subbands.

        Correction:  the  current index should contain both atmosphere cali-
        brations and correlation data; the data file should be open for both
        input  and output.  This command should not affect data taken before
        11-nov-1995 and after 09-jan-1996; be careful for the last day since
        the hour is not checked, and RDI was corrected at 3pm.

      2  Affecting  data  taken  between 26-jan-2015 and 05-mar-2015. Bug in
        correl after change of commons to 7 antennas. Consequence is a phase
        offset  between narrow band correlator units and widex units depend-
        ing on elevation and baseline.

        MODIFY BUG 2 will correct the bug. Warning: this  correction  is  an
        offset to the phases, so it should be applied only once. If the cor-
        rection is done on data file (IPB), there is a check  that  this  is
        the  case, but header files (HPB) are not protected against correct-
        ing twice.

Gildas manager 2022-01-17