Column-conscious Bulk Insert

I am trying to bulk insert a text file. The file has fixed-length fields
with no field terminators. BOL says that field terminators are only
needed when the data does *not* contain fixed-length fields, which
implies they are optional -- so I made a format file without any (two
consecutive tabs with nothing between them). The following message
resulted:

Server: Msg 4827, Level 16, State 1, Line 1
Could not bulk insert. Invalid column terminator for column number
1 in format file

That sounds like I am required to have some sort of terminator in the
format file, even though there aren't any in the data file. Unfortunately,
the documentation on bcp/bulk copy and format files does not directly
address this point, and I would appreciate some help.

BTW, putting '""' (empty string) for the terminator also leads to errors,
with the first field overflowing -- bulk insert can't figure out where
it ends.

Thanks,
Jim Geissman
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