VMS Help DSR, DSR Commands, .TAB STOPS  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    The .TAB STOPS command changes the current positions of tab
    stops. Each tab character in the input file advances the print
    carriage to the right to the next tab stop.

    Format

      .TAB STOPS  [[+/-]n1] [,[+/-]n2]...[,[+/-]n32]

    Abreviated format

      .TS  [[+/-]n1] [,[+/-]n2]...[,[+/-]n32]

1 - Defaults

    o  If you enter the .TAB STOPS command without number or comma
       specifications, the use of all tab stops is suspended and the
       tab character is equivalent to a space.

    o  If you do not enter the .TAB STOPS command, successive tab
       characters work as if you had set a tab stop every eight
       positions; that is, as if you had entered .TAB STOPS 8,16,24,
       and so on. Note that because .PAGE SIZE has a width limit of
       150, 149 is the practical limit for .TAB STOPS.