- 9 -
5.2 Echo Process Section
The flow chart is shown as Figure 6. The front section signal is divided into three lines:
One line is sent by R980 and C958 to N403B's opposite-phase end. This line is just the
signal search and detect circuit we have mentioned before. When the front section
circuit of the microphone has signal output, the auto-search mode will be stopped.
Another line of signal is sent directly after being coupled by R946 and C926. This line is
the stereo channel of the echo channels. The third line is the feedback channel which is
coupled by R947, C927, C928 and R948 and then sent to the echo process IC N905's
th
16 pin. The line is LPF amplified and digitally delayed and then sent out from the pin 14.
The RP 903 connected to the pin 6 is the echo delay adjustment potentiometer. The pin
14's signal is coupled by R951 and R952 into two lines: I
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N905
PT2399
Echo
Processing
Automatic
Search & Detect
Circuit
V902
AMP
N404B
¡¢
N405B
Mix with
the channels
L & R
N904B
.
.
.
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RP903
RP904
(Figure 6)
OK
¡ª
MUTE
- 18 -
59
PORCELAIN
CAPACITOR
50V 683 ±10
£ ¥
5mm
C521,C522
60
PORCELAIN
CAPACITOR
50V 154 +80%-20% 5mm
C527,C528
PORCELAIN
CAPACITOR
100V 104±20
£ ¥
5mm
C412,C414,C402,C404,C458,C459,C434,C460
61
TERYLENE
CAPACITOR
100V 104 ±10% 7mm
C423,C428,C433,C436,C438
62
TERYLENE
CAPACITOR
100V 224 ±10% 8mm
C444,C445
63
TERYLENE
CAPACITOR
100V 472 ±5% 3.5mm
C646
TERYLENE
CAPACITOR
63V 104 ±5% 5mm
C446,C448
64
METAL
POLYESTER
FILM
CAPACITOR
CL21X 63V 153 ±5% 5
C478,C483
65
METAL
POLYESTER
FILM
CAPACITOR
CL21X 100V334±10% 7.5
C479,C482
66
METAL
POLYESTER
FILM
CAPACITOR
CL21X 100V 104 ±10
£ ¥
5
C530
67
CD
CD11 16V10U±20%5×11 2
C465,C466,C507,C508,C531,C405,C415,C539,C648
CD
CD11 25V10U±20%5×11 2
C465,C466,C507,C508,C531,C405,C415,C539,C648
68
CD
CD11 16V22U±20%5×11 2
C427,C432,C422
69
CD
CD11 16V47U±20%5×11 2
C420,C421,C464,C462,C467,C488,C505,C506,C535,C452
C666~C669,C453,C454,C496,C665
70
CD
CD11 16V100U±20%6×12 2.5
C407,C417,C497
71
CD
CD11 50V2.2U±20%5×11 2
C511,C514,C517,C523
72
CD
CD11 50V4.7U±20%5×11 2
C424,C426,C670,C671
73
CD
CD11 25V100U±20%6×12 2.5
C441
74
CD
CD11 25V220U±20%8×12 3.5
C439,C440
76
CD
CD11 35V470U±20%10×20 5
C450,C451
77
CD
CD11 50V100U±20%8×12 3.5
C403,C413,C401,C411
78
CD
CD11 16V1U±20%5×11 2
C435,C437
79
CD
CD11 16V4.7U±20%5×11 2
C469~C476,C481,C485,C486,C489~C494,C538,C640
CD
CD110 35V3300U±20%16×35 7.5 C442,C443
CD
CD11C 50V2.2U±20%4×7 1.5
C520,C526,C529
80
CD
LUA 50V6800U±20%30×50 10
C447,C449
83
MAGNETIC
BEADS
INDUCTANCE
W4B WBC 6×10-1.5T
L405
MAGNETIC
BEADS
INDUCTANCE
100UH ±10% 0410 VERTICAL
10mm
L404
INDUCTANCE
47UH ±10% 0410 VERTICAL
10mm
L406
84
INDUCTANCE
COIL
0.7UH SC-0.8×8.0×11.5
L401,L402
85
CHOKE COIL
UU10.5-1.8mH
L403
86
DIODE
1N4004
VD409
87
DIODE
1N4148
VD440~VD446,VD448,VD449,VD450,VD401,VD402,VD405,
VD406,VD415~VD417,VD419,VD420,VD434,VD412
88
DIODE
RL254
VD421~VD424
89
DIODE
1N5404
VD425~VD428
90
VOLTAGE
REGULATOR
DIODE
3.3V 1/2W
VD447
91
VOLTAGE
REGULATOR
DIODE
4.7V 1/2W
VD410
