c common parameter
      Character*80 freq_spacing, offset_rem, taper, instrument_resp, 
     &     smooth, merge_type, single_component, average_type, 
     &     single_win_out,average_spectra_out, filter_out
      common /parameters/ freq_spacing, offset_rem, taper, 
     &     instrument_resp, smooth, merge_type, single_component, 
     &     average_type, single_win_out, average_spectra_out, filter_out