TM 11-5820-765-34
SOURCE:
Center-tapped secondary winding, transformer T1.
RECTIFIER
BRIDGE
CIRCUIT:
PP-4763
Rectifier
bridge
Z
102.
P P - 4 7 6 3 A Individual divides CR18, CR19, CR20, CR21.
D C OUTPUT Z108 (CR18-CR21):
FILTER:
Resistor-capasitor
filter
circuit
R102(R2);
C103(C3);
R103(R3);
C104(C4).
REGULATOR:
Resistor
R105(R5)
Zener
diodes
CR109(CR9);
CR110(CR10).
PLUS-MINUS
20-VOLT
SUPPLY
CIRCUIT:
Common point connects to power supply's positive output.
PLUS 20-VOLT CIRCUIT:
Supplies reference diode CR104(CR4) through resistor R113(R13).
Output of CR104(CR4) provides bias current to base of transistor Q103(Q3).
MINUS 20-VOLT CIRCUIT:
Supplies voltage divider R107(R7), R115(R15), transmitter-resistor circuit Q103(Q3),
R117(R17).
Second Power Supply to PC101(A1)
SOURCE:
T1,
windings
TB1-11,
TB1-10.
Current passes through current-limiting resistors R6, R7.
RECTIFIER BRIDGE CIRCUIT:
PP-4763
-
Rectifier
bridge
Z101.
PP-4763A - Diodes CR14, CR15, CR16,
CR17.
PULSATING DC OUTPUT, Z101 (CR14-CR17):
Clipped by Zener diode CR109(CR9) through blocking diode CR105(CR5).
Circuit
output
supplies:
Resistor-unijunction transistor circuit R108(R8), R109(R9), Q101(Q1).
Resistor-transistor
circuit
R1
11(R11),
R112(R12),
Q102(Q2).
POWER SUPPLY'S OUTPUT VOLTAGE:
Applied through front panel mounted adjustment assembly A4A2A1R11, A4A2R4 and
A4A2R8, through resistor R120(R20), to base of transistor Q103(Q3).
Base current Q103(Q3) creates current through R117(R17).
Current creates bias voltage for base of Q102(Q2).
This creates current flow through resistors R111(R11), R112(R12).
This supplies capacitor C105(C5).
C105(C5)
connects
through
blocking
CR112(CR12)
to
emitter
of
unijunction
transistor
Q101(Q1).
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