CDO

CDO operators dont work with files that i have in grib1 formart!

When i do cdo sinfo myfile.grb arise the next message:

decodeGDS : Gridtype 1 unsupported
decodeGDS : Gridtype 1 unsupported
decodeGDS : Gridtype 1 unsupported
decodeGDS : Gridtype 1 unsupported
File format: GRIB
-1 : Institut Source Ttype Levels Num Gridsize Num Dtype : Parameter ID
1 : NCEP unknown instant 1 1 8613 1 P16 : 136.129
Grid coordinates :
1 : generic > size : dim = 8613
Vertical coordinates :
1 : generic (ltype=200) : 0
Time coordinate : unlimited steps
RefTime = 1950-05-01 06:00:00 Units = hours Calendar = PROLEPTIC
YYYY-MM-DD hh:mm:ss YYYY-MM-DD hh:mm:ss YYYY-MM-DD hh:mm:ss YYYY-MM-DD hh:mm:ss
1950-06-01 00:00:00 1950-06-01 03:00:00decodeGDS : Gridtype 1 unsupported
1950-06-01 06:00:00decodeGDS : Gridtype 1 unsupported
1950-06-01 09:00:00decodeGDS : Gridtype 1 unsupported

1950-06-01 12:00:00decodeGDS          : Gridtype 1 unsupported
.....

Please, need some tips! Can i do a conversion in way that cdo work?

Thanks