7
(con+.j
PULSE GENERATOR.
The electrical pulses which are used to flash light 5 (or the pulses which flash
light 6) continue as long as the motor continues to run. Pulses like these
are used to automatical I v operate M INIVAC 601 in future experiments.
Most automatic digital computers have a mechanical or electronic device,
similar in function to the rotary switch, to generate a continuous series of
electrical pulses. This is done to make the computer operate continuously
and automatically at speeds much faster than a human could operate a switch.
Continuous pulses, generated to operate a digital computer, are called "clock"
pulses. The use of "clock" pulses in MINIVAC 601 and other digital computers
is explained and demonstrated in future experiments.
PROGRAMMER.
As the motor turns the rotary switch light 5 , and then light 6 , flashes. This occurs in the same
order (sequence), once each revolution of the switch. Other lights could be flashed, or
relays could be energized, in any desired sequence by using other rotary switch terminals.
Thus, it is possible to use the rotary switch to carry out a whole series of operations on the
computer. The particular connections which are made to accomplish a series of computer
operations are called a "program." A ll digital computers, including MINIVAC 601 must be
"programmed" to solve a specific problem. The use of the rotary switch for "programming"
is explained and demonstrated in future experiments.
“ I
1
experim ent
1 4
!
MOTOR REVERSING
I
IJ
Connect power to the
rotary switch motor through
two sets of slide switch contacts
so that the directio n of current
flow through the motor may be
reversed through the sw itch . The
c irc u it looks lik e this:
2. J The program for this c irc u it is:
6
+/
6
R
6
T /
6
U
6 V /D 1 7
6
+/
6
W
6S/D 18
6
- /
6
T
3)
Trace the direction of current flow from
6
+ through the motor to
6
- w ith the switch
in the right position and then again w ith the
switch in the left position. The current
flow through the motor is reversed when
the switch position is changed.
4-)
Turn power O N and notice the d irection
of rotatio n.
This experim ent shows how the direction of rotation
of the motor may be changed by reversing the directio n
of current flow through the motor.
6 +
1
6w
D 1 7
I
The a b ility of the motor to reverse
\
directio n g re atly increases the valu e
of the rotary switch as a programmer.
Many future experiments make use of
the basic fact that the d irection of
rotation may be reversed by reversing
\ the current flow through the motor,
j
5J
Chonge the position of switch
6
. The motor reverses
direction ond the pointer knob turns in the opposite d irectio n .
24
Summary of Contents for Minivac 601
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