Notes On Schematic Diagram; Types Of Transistor And Led; Voltage - Sharp QT-90W Service Manual

• Resistor:
To differentiate the units of resistors, such symbol as K and
M are used: the symbol K means 1000 ohm and the symbol
M means 1000 kohm and the resistor without any symbol is
ohm-type resistor. Besides, the one with "Fusible" is a fuse
type.
• Capacitor:
To indicate the unit of capacitor, a symbol P is used: this
symbol P means pico-farad and the unit of the capacitor
without such a symbol is microfarad. As to electrolytic
capacitor, the expression "capacitance/withstand voltage"
is used.
(CH), (TH), (RH), (UJ): Temperature compensation
(ML): Mylar type
(P.P.): Polypropylene type
• Schematic diagram and Wiring Side of P.W.Board for this
model are subject to change for improvement without prior
notice.
• Parts marked with "
maintaining the safety of the set. Be sure to replace these
parts with specified ones for maintaining the safety and
performance of the set.
• The indicated voltage in each section is the one measured by
Digital Multimeter between such a section and the chassis
with no signal given.
IC101: LA1186N [FM]
Pin No. 1 2

Voltage

0.9V 1.5V 5.3V 0V
IC102: LA1805 [FM]
1 2
Pin No.
Voltage 1.5V 1.5V 5.5V 2.2V 1.5V 0V
Pin No. 13 14
1.1V 1.5V 1.5V 1.2V 2.3V 0.22V 0.12V 5.5V 5.5V 0V
Voltage
IC102: LA1805 [MW/SW1/SW2]
1 2
Pin No.
Voltage 1.55V 1.55V 6.7V 0.8V 1.55V 0V
Pin No.
13 14
Voltage 0V 1.65V 1.1V 1.2V 1.65V 0.8V 0.55V 6.7V 6.5V 1.6V 1.6V 1.6V
IC201: BA3313L [PLAYBACK]
Pin No. 1 2
Voltage 2.7V 0.25V 6.6V
IC201: BA3313L [REC]
Pin No. 1 2
2.8V 0.26V 6.4V 0V
Voltage
IC401/IC402: BA5415A
1 2
Pin No.
Voltage 15V 7.7V 15V
Q601: 3DA8050
Pin No. 1 2 3
Voltage
E:7.5V B:17V C:8.2V

NOTES ON SCHEMATIC DIAGRAM

" ( ) are important for
3 4 5 6
0V 5.3V 0V
3 4 5 6
15 16 17 18
3 4 5 6
15 16 17 18
3 4 5 6
0V 6.9V 0V
3 4 5 6
6.8V 0V
3 4 5 6
0.6V 5V 5.2V 15V
Q602: SS8550
1 2
Pin No.
E: 17V C: 17V B:17V
Voltage
REF. NO
S101
S201
S301
S501
SW501
SW601

TYPES OF TRANSISTOR AND LED

FRONT
VIEW
E C B
2SC945
3DA8050
SS8550
VOLTAGE
7 8 9
4.7V 5.3V
7 8 9 10
0V 0V 2V 2V
19 20 21 22
7 8 9 10
0V 0V 2V 2V
19 20 21 22
7 8 9 10
0V 0V 0V 5.2V 0V
7 8 9 10
0V 0V 0V 0.265V 0V
7 8 9 10
0V 0.6V 15V 7.8V
Q603: SS8550
3
1
Pin No.
Voltage E: 17V C: 17V B: 0V
– 9 –
DESCRIPTION
BAND SELECTOR
RECORD/PLAYBACK
FUNCTION/
BEAT CANCEL
VOLTAGE SELECTOR
SURROUND
TAPE MAIN
FRONT
VIEW
FRONT
VIEW
E B C
CSL-326G3GTH
Q201: 3DA8050
Pin No. 1
Voltage E: 7V B: 6.7V C:7.6V
Q205: 2SC945
Pin No. 1
11 12
E: 0V C: 3.5V B:0.5V
Voltage
4.8V 0.8V
23 24
Q207: SS8550
1.6V 0.8V
Pin No. 1
Voltage E: 7.5V C: 7.5V B: 0V
Q209: 2SC945
11 12
1
Pin No.
6.5V 0.8V
Voltage
E: 0V
23 24
Q301: 2SC945
1
Pin No.
Voltage E: 0V
11 12
Q303: 2SC945
3V
1
Pin No.
Voltage E: 0V
11 12
Q304: 2SC945
3V
Pin No. 1
E: 0V C: 0V
Voltage
11 12
Q305/Q306: 2SC945
0V
Pin No. 1
Voltage E: 0V
2 3
QT-90W
POSITION
FM—MW—SW1—SW2
REC—P.B.
LINE
AC 220-240 V—
AC 110-127 V
OFF—ON
OFF—ON
FRONT
VIEW
523HD
2 3
2 3
2 3
2 3
C: 0V B: 5V
2 3
C: 4V B:0.7V
2 3
C: 0V B: 5V
2 3
B: 5V
2 3
C: 4V B:0.7V