VMS Help TN3270, Qualifiers, /CHARACTER_SET  *Conan The Librarian (sorry for the slow response - running on an old VAX)

       /CHARACTER_SET=file

    Optional. Default: ORIGINAL.

    File with the EBCDIC-to-DMCS (DIGITAL Multinational Character
    Set) and the DMCS-to-EBCDIC translation tables.

    If you omit this qualifier, TN3270:

    o  Uses the translation table named by the default file
       SYS$LIBRARY:TN3270DEF.TBL, if your system manager has created
       it.

    o  Defaults to its own translation table, if TN3270DEF.TBL does
       not exist. The default table maps the US EBCDIC set to the
       equivalent DMCS characters.

       If none of these translation tables meets your needs, the
       system manager can generate a new translation table. (See
       the Compaq TCP/IP Services for OpenVMS Management manual for
       information about the EBCDIC / DMCS translation tables.)

                                      NOTE

          To reset the default, do not abbreviate ORIGINAL.