This tape is labeled:

Processor Technology; Extended Cassette BASIC; P/N 727019

It contains:

BASIC B 0000 3F85
END   ? FFFF 0001
BASIC B 0000 3F85
END   ? FFFF 0001

I rarely used this program because it was too big to use with my tape player, 
it required me to relocate my Northstar Dos to a place I didn't want it, it 
was slow, and the math package wasn't that strong.


[ JTB NOTE:
    extbasic.ent and extbasic_orig.ent are identical, and in fact one
    is a copy of the other.  this is the pristine source.  it has a bug
    where:

        10 FOR I=1 TO 0
        20 FOR K=1 TO 0
        30 PRINT "impossible"
        40 NEXT K
        50 NEXT I

    will cause a CS (control stack) error.  P.T. put out an errata
    sheet with a small patch to fix this bug.  That has been applied
    and is in the file extbasic_patched.ent.  This indeed fixes this
    problem.  However, when running "ROMLN.BAS" (which uses a lot of
    "NEXT 180" type statements and fiddles with the control index),
    we get a CS error with the patched version but not the original
    version.  Doh.
]