Sony SRF-M95 Service Manual ▷ View online
3
SRF-M95
SECTION 2
DISASSEMBLY
Note :
Follow the disassembly procedure in the numerical order given.
2-1. MAIN BOARD, SUB BOARD
1
Screw (1.4
×
10)
1
Screw (1.4
×
10)
9
SUB board
7
Cover (Jack)
1
Screw (1.4
×
10)
5
Flexible board
4
Screw
6
MAIN board
3
Cabinet (front) assy
2
Six claws
8
Screw
4
SRF-M95
SECTION 3
ADJUSTMENTS
Setting:
BAND switch: AM
Connection:
BAND switch: AM
Connection:
For AM frequency coverage adjustment and FM frequency coverage check.
AM Section
digital
voltmeter
voltmeter
TP (VT)
Connection:
AM RF signal
generator
generator
30% amplitude modulation by
400 Hz signal.
Output level: as low as possible
400 Hz signal.
Output level: as low as possible
Put the lead-wire
antenna close to
the set.
antenna close to
the set.
level meter
set
headphone jack (
i
)
16
Ω
+
–
–
FM Section
FM RF signal
generator
generator
22.5 kHz frequency deviation
by 400 Hz signal.
Output level: as low as possible
by 400 Hz signal.
Output level: as low as possible
0.01
µ
F
TP (ANT)
FM VCO Adjustment
Setting:
BAND switch:
FM
FM SENS switch: DX
Procedure:
1.
Turn off the FM RF signal generator.
2.
Put a capacitor (100
µF) between pin ws (IC201) and GND.
3.
Put a resistor (100 k
Ω) between TP (VCO) and GND.
4.
Tune the set to 87.5 MHz.
5.
Adjust RV201 for 19 kHz
± 0.05kHz reading on the frequency
counter.
AM FREQUENCY COVERAGE ADJUSTMENT
Adjust for a reading on digital voltmeter.
T201
531 kHz (530 kHz) [531 kHz]
1.3V
± 0.1V
Confirm
1,602 kHz (1,710 kHz) [1,710 kHz]
10 V or less
AM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter.
CT201
1485 kHZ (1480 kHz)
L201
585 kHz (590 kHz)
FM FREQUENCY COVERAGE CHECK
Check a reading on digital voltmeter.
Confirm
87.5 MHz [76.0 MHz]
3.5V [0.9 V] or more
Confirm
108.0 MHz
11V or less
FM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter.
CT101, CT102
108.0 MHZ
L104
87.5 MHz [76.0 MHz]
( ) : Panama model [ ] : Tourist model
Connection:
frequency counter
TP (VCO)
Setting:
BAND switch:
BAND switch:
FM
FM SENS switch: DX
Connection:
Adjustment Location
[MAIN BOARD]
(SIDE B)
[MAIN BOARD]
(SIDE A)
IC401
CN401
IC201
GND
TP(VCO)
GND
GND
TP(ANT)
TP(VT)
TP(pin
ws
)
IC101
CT101
CT102
CT201
L201
L104
FM TRACKING
Adjustment
Adjustment
AM TRACKING
Adjustment
Adjustment
T201
AM FREQUENCY
COVERAGE Adjustment
AM FREQUENCY
COVERAGE Adjustment
RV201
FM VCO
Adjustment
FM VCO
Adjustment
5
5
SRF-M95
SECTION 4
DIAGRAMS
4-1. BLOCK DIAGRAM
FM/AM RF,IF AMP
IC201
T202
AM MIX
CF202
450kHz
MIX OUT
4
FM IF IN
3
AM IF IN
6
AM OSC
L OUT 14
R OUT 15
ON
OFF
: FM
• Signal Path
• RCH is omitted
: AM
RF IN
1
6
MIX
8
RF OUT
5
OSC
FM FRONT END
IC101
D101
FM IF
AMP
Q102
CF101,102
10.7MHz
L201
BAR ANT
AM RF
24
Q201
RF
AMP
T201
AM OSC
2
D201
7
QUAD
17
VCO
VCO
RV201
CF203
10.7MHz
AUDIO
POWER AMP
IC301
40
DO
TU VCC
Q101
LOCAL
/DX
EXCEPT
JE
MODEL
D102
Q103
TU VCC
LPF1
16
Q204
LOCAL
/DX
JE MODEL
FM
DX
LOCAL
OFF
ON
TU VCC
L.P.F
Q403
Q403
CT201
DET OUT
22
PILOT IN
21
MPX IN
20
Q205
LPF 2A
18
LPF 2B
19
Q203
BAND
TU VCC
TU VCC
Q202
TU VCC
Q303
S304
Q302(1/2)
IN L
27
Q302(2/2)
IN R
28
S305
MEGA
BASS
VOL
RV301
TU VCC
NF L
26
NF R
29
REF OUT
3
BST SW
43
PW SW
42
MT SW
41
Q301
TU VCC
VCC
BASE
18
OUT L 22
OUT C 21
OUT R 20
AGC IN 35
J301
TU VCC
Q104,105
IC101
+B
DC-DC
CONV
T401
Q402,405
VCC
Q401
38
OSC IN
31
DDC ON
52
BAND
53
AM PON
50
MUTE
28
BEEP
X OUT
55
LCD1
LIQUID CRYSTAL
DISPLAY
X IN
56
X401
75kHz
1
4
COM1 COM4
5
16
S1 S12
INT2
34
VDD
IF
COUNTER
1
2
INT1
35
IF INT2
36
VCC
IC402
HOLD SW
26
HOLD
S303
KR1
23
DIGITAL TUNING
SYSTEM CONTROL
IC401
POWER
KR2
24
KR3
25
KS1
21
KS2
-2
S401
MODE
S302
-1
-3
22
S301
JOG
DRY BATTRY
SIZE "AAA"
(IEC DESIGNATION R03)
1PC 1.5V
Q406
VDD
IC403
VCC
RESET
RESET 54
POWER ON 51
• Abbreviation
JE
: Tourist model.
Ver 1.1 2002. 02
6
6
SRF-M95
4-2. SCHEMATIC DIAGRAM –MAIN SECTION–
• See page 10 for IC Pin Function. • See page 10 for IC Block Diagrams.
1
IC101
tg
XOUT
960 mVp-p
14
µ
sec
TIME/div : 10
µ
sec/div
VOLT/div : 200 mV/div
2
2.1 Vp-p
0.34
µ
sec
TIME/div : 0.1
µ
sec/div
VOLT/div : 500 mV/div
Note on Schematic Diagram:
• All capacitors are in
• All capacitors are in
µ
F unless otherwise noted. pF:
µµ
F
50 WV or less are not indicated except for electrolytics
and tantalums.
and tantalums.
• All resistors are in
Ω
and
1
/
4
W or less unless otherwise
specified.
•
C
: panel designation.
•
A
: B+ Line.
•
H
: adjustment for repair.
• Power voltage is dc 1.5 V and fed with regulated dc power
supply from battery terminal.
• Voltages and waveforms are dc with respect to ground
under no-signal (detuned) conditions.
no mark : FM
<
no mark : FM
<
> : AM
• Voltages are taken with a VOM (Input impedance 10 M
Ω
).
Voltage variations may be noted due to normal produc-
tion tolerances.
tion tolerances.
• Waveforms are taken with a oscilloscope.
Voltage variations may be noted due to normal produc-
tion tolerances.
tion tolerances.
• Circled numbers refer to waveforms.
•
•
Signal path.
F
: FM
f
: AM
• Abbreviation
JE
: Tourist model.
PA
: Panama model.
• Waveform
L104
EXCEPT JE
IC B/D
IC B/D
2
Ver 1.1 2002. 02