Fairchild Teletypesetter Standard Perforator Description
§ § § § § §
FOR EFFICIENT OPERATION of the Teletypesetter Perforator, it is necessary for the Operator to be able to read the tape. Before an Operator is permitted to set "live copy," the alphabet, shift, unshift,
return, and elevate combinatio ns should be memorized. Referring
to upper figure, it
should be noted that the uppermost or zero perforation is only used for figures, special characters,
The code combinations are arranged in six groups to assist the operator in locating the code
combinations for identification purposes.
After operating the keyboard for a short time, the Operator will soon become familiar with the group of
combinations that start with the zero perforation. They are easily learned by associating them with
corresponding letter combinations. For instance, the "w" and "2" when perforated, are alike except
that the "2" has the zero perforation added. Perforations of characters E, R, T, Y, U, I, 0, and P are
similar to the perforations of the figures located above these characters on the keyboard, except that
the figures have the zero perforation added. Other character combinations have equal similarity and
may be memorized in the same manner.
Code chart (right) in which the code
combinations are arranged in groups to facilitate memorizing the
code. The thin space, E, ELEV, SPACE, RET, and T are all single perforations and differ only in
location in the tape, each perforation located one code
interval below the preceding perforation. The code combinations
for the remaining letters of the
alphabet are conveniently grouped in a similar manner.
Next figure shows the position in which tape should be held when reading.
The tape should be read from left to right, holding the tape in the same position as fed from the
perforator. When tape is held in the proper position, tape feed holes are located in line with the left
edge of the code perforations. Having determined the right and left ends of the tape in this manner, the
top surface of tape may be identified by a greater number of
perforations in the fifth position than in the zero position.
After the combinations have been memorized, the
next step is to secure some
perforated tape and practice tape reading. For practice purposes, the character represented by each
combination may be written above the combinations in the tape.
FIGURE 55 SHOWS VARIATIONS that may occur in printed copy as compared with typewritten matter.
This example should be studied carefully and the following characteristics noted:
Variations in width of characters (for example, "m" compared with "i" in the word "medium") .
Variations in width of spacing between
words in a given line and in different lines.
Even margins, both right and left hand.
The spacing between words in
typewritten copy is uniform, whereas the spacing between words of printed copy, although uniform
throughout a given line, is not the same for all lines. It will be noted that the amount of space between
the words in the first three lines of (above figure) is less than that in the last three lines. Good printing
requires close spacing between words.
This variable width of spacing between words in printed copy is accomplished by the spacebands on
the linecasting machine which are wedge shaped and automatically expand the spacing between
words to fill out the line. Thus even margins are achieved at both the right and left-hand sides of the
copy- a process known as "line justification."