Scientific Development Corporation Minivac 601, Знакомство с устройством, Страница: 19 / 36

EXPERIMENT
— I
IJ
The program for this c irc u it is:
J
I F /
1
-
2
Y /
2
+
1
C/1 X 2 Z /1 L
1 Y / 2 Y 1 K /1 C
A RELAY CONTROLS ITSELF
I his experim ent demonstrates how a re la y
may be used to control its own operation.
The re la y is connected to remain O N when it
is turned O N , and to remain O FF when it is
turned O F F . The re la y remains in one of the
two conditions (O N or O F F ) until signalled
by one of the pushbuttons to change to the
Push pushbutton 1 and re le a se . The
re la y in d icato r lig h t comes O N and stays
O N . The re la y stays O N because an e le c tric
c irc u it is completed through its own contacts
to energize the c o i l .
Push pushbutton 2 and re le a se . This
m om entarily interrupts current flow
through the coil and turns the re la y O F F .
The re la y in dicato r light turns O F F and
shows that the re la y is no longer e n erg ized .
The re la y c irc u it has now returned to its
original co n d itio n .
O perate the c irc u it back and forth ^ '
a few times by first pushing push­
button
1
; then pushbutton
2
.
The c irc u it used in this experim ent is ca lle d
"b istab le" because it is able to remain in
either of two stable co ndition s. Many
d ifferent types of "b istab le" c irc u its are
used in modern dig ital computers.
t +
The two stable conditions of the re la y c irc u it
(O N and O F F ) are used by the computer in later
experiments to represent two numbers. When the
re la y is O F F , the number zero (0) is represented.
When the re la y is O N , the number one (1) is
represented. The re la y c irc u it thus remembers
(stores) these binary numbers.
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IN
2X
1Z
iy
I X
1C
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