Sylvania SRD4900 Service Manual page 41

Main CBA Bottom View
CAUTION
FOR CONTINUED PROTECTION AGAINST FIRE HAZARD,
F REPLACE ONLY WITH THE SAME TYPE FUSE.
ATTENTION : POUR UNE PROTECTION CONTINUE LES RISQES
A V D'INCELE N'UTILISER QUE DES FUSIBLE DE MÊME TYPE.
RISK OF FIRE-REPLACE FUSE AS MARKED.
"This symbol means fast operating fuse."
"Ce symbole reprèsente un fusible à fusion rapide."
NOTE :
The voltage for parts in hot circuit is measured
using hot GND as a common terminal.
1-10-21
WF4 WF5
WF7 WF8
PIN8 OF PIN10 OF PIN 14 OF PIN 16 OF
CN1601 CN1601 CN1601 CN1601
CAUTION !
Fixed voltage ( or Auto voltage selectable ) power supply circuit is used in this unit.
If Main Fuse (F1001) is blown, check to see that all components in the power supply
circuit are not defective before you connect the AC plug to the AC power supply.
Otherwise it may cause some components in the power supply circuit to fail.
BECAUSE A HOT CHASSIS GROUND IS PRESENT IN THE POWER
SUPPLY CIRCUIT , AN ISOLATION TRANSFORMER MUST BE USED.
ALSO , IN ORDER TO HAVE THE ABILITY TO INCREASE THE INPUT
SLOWLY , WHEN TROUBLESHOOTING THIS TYPE POWER SUPPLY
CIRCUIT , A VARIABLE ISOLATION TRANSFORMER IS REQUIRED.
WF6 WF9
PIN 14 OF PIN 19 OF
IC1402 CN1601
MAIN CBA
Ref No.
ICS
IC301
IC451
IC501
IC751
IC1001
IC1002
IC1004
IC1201
IC1402
TRANSISTORS
Q031
Q052
Q055
Q056
Q057
Q301
Q302
Q303
Q391
WF10
Q421
PIN 2 OF
Q422
TU701
Q425
Q426
WF11
Q501
PIN 6 OF
Q506
Q563
TU701
Q565
Q566
WF12
Q567
PIN 11 OF
Q1001
TU701
Q1003
Q1004
Q1005
WF13
Q1006
PIN 12 OF
Q1008
TU701
Q1011
Q1201
Q1202
Q1204
Q1351
Q1385
Q2002
WF15
Q2013
PIN 18 OF
CONNECTORS
TU701
CL253
CL501
CL502
CL504
CL1001
CL1601
CL2003
VARIABLE RESISTOR
VR501
TEST POINTS
TP301
TP302
TP502
TP505
TP506
TP507
TP513
TP751
TP753
TP754
1-10-22 BH9600F01011A
Position
C-4
B-4
C-2
B-5
F-5
G-2
G-2
B-5
E-4
F-5
F-3
F-2
F-2
F-2
C-3
C-3
C-3
D-5
D-4
C-4
D-4
D-4
B-1
C-3
B-1
B-1
F-1
E-1
G-4
G-4
G-3
G-1
G-2
G-5
G-2
F-5
F-5
D-5
G-5
C-5
G-1
G-1
B-4
A-5
E-3
D-4
G-1
E-4
G-1
A-2
A-3
A-3
E-1
A-3
F-3
A-3
A-2
F-5
E-5
F-5