Yamaha CS-50 Servicing Manual page 62

G
RING MODULATION SIGNAL OSCILLATOR
SPEED
From speedl
lever
VCI
1
lOOK
330K
-15V
From controlled
voltage generator
t
VC2
To ring modulator
TP2
+
15
150K
B-500K
VR3
This circuit is a VCO controlled by the voltage from the control voltage generator through SPEED and DEPTH
control levers. Its output is used as the modulation signal (variable for 0.2 - 220 Hz). For the principle of
operation, see the section on the PWM oscillator.
• CONTROL VOLTAGE GENERATOR
To DEPTH control---,
From K09 terminal---.,
of KAS sheet
VRl
Eo
ATTACK
TIME
IT
DECAY
TIME
DT
3.3K
8-20K
~
....
\--"""--14---f-+--~'-------'
In this circuit, the rising and fast-decaying envelope voltages are controlled on the basis of key-ON signal from the
KAS circuit board by use of ATTACK TIME and DECAY TIME controls, and the output is fed into the ring
modulation signal oscillator through the DEPTH control. For the principle of operation, refer to the section
of envelope generator.
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