Card Punching - IBM 1130 User Manual

Section
Subsections Page
90 30
I
20
02
The 2501, because of its clutch arrangement,
requires a special analysis. The 2501-A1, the 600-
card-per-minute reader, will read at fixed speeds of
600 cpm (100 millisec)
300 cpm (200 millisec)
200 cpm (300 millisec)
150 cpm (400 millisec)
120 cpm (500 millisec)
100 cpm (600 millisec)
etc.
and the 2501-A2, the 1000-card-per-minute reader,
will read at fixed speeds of
1000 cpm (60 millisec)
500 cpm (120 millisec)
333 cpm (180 millisec)
250 cpm (240 millisec)
200 cpm (300 millisec)
166 cpm (360 millisec)
etc.
To calculate the expected improvement in timing
due to a 2501-A1, we must, as before, substitute
100 milliseconds for the 200 milliseconds (1442-6),
to get 2100 x 100 or 210,000 milliseconds read
time, add the 180,000 milliseconds other time,
obtaining 390,000 milliseconds or 15 minutes.
Dividing this into the number of cards read (3000),
we find that this yields a rate of 323 cards per
minute.
However, the clutch arrangement of the 2501-A1
will not allow it to run at 323 cards per minute, so
the next lower speed (300 cpm) must be assumed.
2100 cards at 300 cpm yields a total time of seven
minutes.
A similar analys is for the 2501-A2 gives a
theoretical speed of 412 cpm, but, choosing the next
lower speed, 333 cpm., the total run time is calCU-
lated as 6.6 minutes.
Card Punching
Three different card punches are available for use on
the 1130 system; all three operate in the same mode,
punching one column at a time.
Card Punch Millisec0nds per Card Column
Punched or Spaced
1442 Model 6 12. 5 plus 12. 5 per column
1442 Model 7 6. 5 plus 6. 5 per column
1442 Model 5 6. 5 plus 6. 5 per column
Models 6 and 7 both read and punch; Model 5 only
punches.
The overall speed is determined by the last
column punched, rather than the l'lIlmlber of columns
punched. If you skip the first 20 columns and punch
into the 21st, you have punched or spaced 21 columns
and the time for that number will apply. Figure
90.10 gives the punching time for the three models,
as they vary with the last column punched.
To continue the previous example, suppose that
of the 2100 cards read, the program punched into
1000
900
800
700
600
VI
"0
c:
0
500
(,.)
~
~
400
300
200
100
o
10 20 30 40 50 60 70 80
Last Column Punched
Figure 90.10.