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E L E C T R I C A L
P R I N C I P L E S
117
The suppressors of all the multiply control
switches are tied together to the voltage divider
shown under switch C3 (Section 32A). This
voltage divider consisrs of equal resistors between
the -100 volt line and ground; consequently, all
suppressors are normally at -50 volts which is well
below cutoff for this element. All suppressors re-
ceive a $12 pulse through the .O2mfd coupling
capacitor, which transmits pulses from the mulri-
plier advancing power tube A36. Each time A36
produces a positive pulse, all suppressors rise above
cutoff. However, only the switch conditioned for
operation during the given column shift cycle can
conduct.
This switch will then conduct for a
brief instant at 12 and produce a -100 volt nega-
tive pulse at its anode. Since triggers are operated
on -50 volt pulses, the output to the multiplier
counter is taken from the midpoint of the load re-
sistor for the multiplier input switch.
From rhis
it is evident that one position of the multiplier
counter will advance 1 at 12 of each primary cycle,
the particular position being determined by the
column shift cycle.
Primarv Timer
Q
I
A
Chossisl
ON 0
M'Pliar
OFF
I 2
The purpose of the 100 mmfd capacitor across
the .56 megohm resistor in the grid circuit of the
C18 tube shown in Figure 110 is to permit in-
stantaneous changes at the grid by counteracting
the effects of interelectrode capacitances. The 4700
ohm resistors in the suppressor circuit prevent
parasitic oscillations.
The multiplier counter, which receives its entry
pulses from the C chassis, consists of six standard
electronic counter positions on chassis E, F, and
G.
The multiplier counter chassis are identical to the
counters previously described.
It
might be men-
tioned that no provision is made for carry in the
multiplier counter because there is no need for
carrying in this counter or the multiplicand
counter.
Figure 11 1 shows a block diagram of the multi-
plier advancing circuits, indicating all tubes in-
volved as well as the operations. The secrion to
the right shows how the multiplier output control
determines the number of times the multiplicand
receives rolling pulses. This operation is discussed
in d&ail in the following paragraphs.
I
1
1
M m a s i s
Control
Power Tubes
Multiply
MoP11.r
M'Plier
Control
counter
Outpul
switchas
1nvsrt.r~
( C Chossis
I
l
E F G C h o s ~ l s l
I H
Chossis
I
Figure 111. Block Diagram o f Multiplier Advancing Circuits
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