Glossary
Of Features
PHYSICAL
ATTRIBUTES
Enclosed Paper Roll
Most calculators (with the exception of Monroe
heavy duty models) have the paper roll mount-
ed externally. The most expensive component
of a print/display calculator is the printer. It is
also the component most likely to fail, as it is
an electro-mechanical mechanism. The most
common cause of printer failure is dust and dirt
collecting on the paper roll and falling into the
print mechanism as the paper is fed through
the printer. By enclosing the paper roll, Monroe
protects the paper roll and by extension the life
of the printer from this common cause of print-
er failure. If the paper roll is external, it also
means paper roll holders (typically plastic) are
mounted externally to hold the paper roll. It is
almost certain these paper roll holders will be
lost or broken during the course of use. At the
very least, this design means the operator will
be forced to replace paper roll holders during
the life of the calculator, replace the calculator
or come up with some inventive method for
supporting the paper roll when the holders are
lost or broken.
Another drawback to mounting the paper roll
externally is the typically cluttered desk of
most users. If the paper roll is lodged against a
book, stack of papers or some other object on
the desk, it is likely the paper cannot advance
or move through the print mechanism. As most
touch operators do not look at the calculator
during addition columns, such an operator
would be both surprised and disappointed to
look at the tape after listing a long column of
figures and see a black smudge on the tape
rather than the answer. Again the enclosed
paper roll design eliminates this possibility. The
expected life of the print mechanism is 3 million
lines of print. The enclosed paper roll enhances
the ability of the printer to reach its expected
life.
Print Quality
There are at least three factors affecting the
quality of print on the paper tape. The obvious
one of course is the ribbon. The other two
common factors are the paper (thickness) and
the manufacturing variance of the printer (dis-
tance between the platen and print wheel).
Monroe carefully selects both ribbon and paper
supplies to optimize print quality. While both
supply items are readily available, the quality of
the ribbon and the quality of the paper vary
greatly when obtained from sources other than
Monroe.
Keyboard Layout
Today’s calculators are descended from yester
years mechanical adding machines. All
mechanical adding machines had all adding
machine controls (+, -, subtotal and total) to the
right of the numeric keypad. Recalling that the
most often used function of a calculator is
addition and subtraction, adding machine con-
trols must be located on the right of the numer-
ic keypad.
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