> MOUNT/FOREIGN/BLOCK=512 MUA0: and
> COPY TK50-FILE1-13A.; MUA0:
> 
> require the input file to be blocked at 512, rather than variable length
> records. The copy fails with a record length error.
> 
> I recall that I can use EDIT/FDL to create an FDL file under VMS that
> specifies 512 byte records, then use CONVERT/FDL to convert the existing
> FILE1 and FILE2 to 512 byte versions, which can then be copied to tape.
> 
> I played around but did not get the FDL file correct.

Far easier is to use Joe Meadow's FILE utility, available at all
the fine VMS freeware sites, such as ftp://ftp.wku.edu/vms/fileserv/file.zip.
After setting it up, just do

$ FILE TK-50-FILE1-13A./RECORD_SIZE=512/TYPE=FIXED

and you'll be in fat city.

Tim.