Sharp DV-5145, Service Manual

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1. Outline of
(3)
(4)
(5)
(7)
PIF amplifier of sync demodulator type
Negative modulation AGC detector circuit
Tuner RF AGC
AFC circuit
Video preamplifier
Sound IF amplifier and demodulator circuit
Horizontal oscillator drive circuit/horizontal oscilla-
tor/horizontal output circuit
Audio preamplifier
Horizontal sync circuit with two control loops
Sawtooth wave generator/vertical sync circuit with
automatic amplitude control cir-
cuit
Sand castle pulse generator circuit
2. Pins arrangement
Figure 2-l.
3. Function
Pin AGC cut-in level
Pin Generation of vertical sawtooth wave
Pin Vertical drive output
Pin Vertical feedback circuit (correction of vertical
linearity and size)
Pin Tuner RF AGC
Pin PIF ground
Pin Power B (1 IV)
Pin IF input
Pin IF input
Pin IF decoupling capacitor
Pin Sound volume control
Pin Audio output
Pin SIF detection
Pin SIF decoupling capacitor
Pin SIF input
Pin oscillator ground
Pin Video output
Pin AFT
Pin AGC detector
Pin IF sync detector circuit
Pin IF sync detector circuit
Pin Sync circuit
Pin
Pin
Pin
Pin
Pin
I
I
I
I
Figure 2-2.
Horizontal oscillator circuit
AFC circuit (1st control loop for frequency con-
trol)
Sync separator circuit (to decide sync separa-
tion level)
Horizontal drive output circuit (also works as
horizontal drive pulse input circuit.)
Sand castle output
Figure 2-3.
l
Pin Phase-II detector (APC circuit 2nd control loop
for phase control)
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