Scientific Development Corporation Minivac 601, Getting Acquainted

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PUSHBUTTONS
he section of the computer panel labeled "B in ary Input" contains
six id en tical pushbuttons w hich are used by the operator to supply
information to the computer. The pushbuttons may be used to te ll the
computer what to do, or to in d icate the valu e of input numbers.
Pushbuttons may be used to control the other components of M IN IV A C 601
Each pushbutton is id en tified by its section number on the computer p a n e l.
Each of the s ix binary input pushbuttons has three term inals located d ire c tly
above it on the computer p a n e l. Each terminal is connected under
the panel to a co n ta ct. The term inals are labeled X , Y and Z .
The three contacts for each of the six
pushbuttons are a ll connected to term inals in the same manner:
When the pushbutton is U P , an e le c tric a l
connection is made between term inals Y
and Z . When the pushbutton is D O W N ,
the e le c tric a l connection is switched to
term inals Y and X . Terminal Y is connected
to the "common" contact and is alw ays used when
the pushbutton is connected in a c ir c u it .
When a pushbutton is shown in a c irc u it
diagram , the contacts are A L W A Y S shown
w ith the pushbutton UP - in the "norm ally
closed" ( N . C . ) position. N o tice that
term inals X and Y are not connected when
the pushbutton is U P , and that term inals
Y and Z are not connected when the
pushbutton is D O W N .
up= y/z
i r : l
j
!*2.
D
owm
=
x
/
y
The follow ing experiments demonstrate basic c irc u its in w hich
one or two pushbuttons are used w ith a lig h t.
♦
N