These are three versions of the Fast Tape Copy Program, TPC. TPC79F
is the version distributed on the 1979 Spring (New Orleans) and Fall (San Diego)
DECUS tapes. TPCNEW has been modified to correct a problem in reporting
error numbers (Negative byte codes were being printed as positive word values).
BIGTPC is the same as TPCNEW with an additional modification to allow copying
tapes with very large records (<=4200. bytes). This allows TPC to copy DSC
or BRU tapes. (I haven't tried it with DSC, but it works quite nicely with
BRU tapes. DSC tapes have slightly smaller records than BRU tapes so there
should be no problems there.) BIGTPC takes a full 32K and should only be used
if you need its additional capability.

All changes are marked with the comments "++AF1" (TPCNEW & BIGTPC) and
"++AF2" (BIGTPC only).