Sony SRFT-615 Service manual
SRF-T615
SERVICE MANUAL
Ver 1.0 1999.10
SPECIFICATIONS
Tourist Model
MICROFILM
FM STEREO/AM PLL SYNTHESIZED RADIO
TABLE OF CONTENTS
Specifications ........................................................................... 1
1. GENERAL
Location and Function of Controls .................................... 2
2. DISASSEMBLY
2-1. Cover (JOG) (A) ......................................................... 3
2-2. Lid, Battery Case ........................................................ 3
2-3. Cabinet (Rear)............................................................. 4
2-4. Main Board ................................................................. 4
3. ADJUSTMENTS .......................................................... 5
4. DIAGRAMS
4-1. Explanation of IC Terminals....................................... 7
4-2. Block Diagrams .......................................................... 9
4-3. Printed Wiring Boards .............................................. 12
4-4. Schematic Diagram................................................... 15
5. EXPLODED VIEW..................................................... 19
6. ELECTRICAL PARTS LIST.................................... 20
Flexible Circuit Board Repairing
• Keep the temperature of the soldering iron around 270°C during
repairing.
• Do not touch the soldering iron on the same conductor of the
circuit board (within 3 times).
• Be careful not to apply force on the conductor when soldering or
unsoldering.
Notes on chip component replacement
• Never reuse a disconnected chip component.
• Notice that the minus side of a tantalum capacitor may be damaged by heat.
LOCATION AND FUNCTION OF CONTROLS
SECTION 1
GENERAL
This section is extracted from
instruction manual.
– 2 –
DISASSEMBLY
e
r
The equipment can be removed using the following procedure.
SECTION 2
Set
Cover (JOG) (A)
Lid, Battery Case Cabinet (Rear) Main Board
Note : Follow the disassembly procedure in the numerical order given.
2-1. COVER (JOG) (A)
1
Screw (B1.7x9)
Cover (JOG) (A)
3
Turn from upper side
of the cover (JOG) (A),
2
Three claws
and remove it.
2-2. LID, BATTERY CASE
Lid, battery cas
3
Two claws
2
1
– 3 –
2-3. CABINET (REAR)
s
y
1
Screw (1.7x9)
5
Button (MENU)
Cabinet (rear)
4
Knod (HOLD)
Cabinet (front) ASSY
3
2
Claw
2
Two claws
2
Two claws
2
Two claw
2-4. MAIN BOARD
Terminal (–) (A), battery
Main board
3
Remove solder
1
Lead wire (Black)
4
Terminal (+) (A), batter
2
Screws (1.4)
Brown
Cabinet (front) ASSY
Black
– 4 –
SECTION 3
)
r
D
C603
5
5
r
ADJUSTMENTS
TUNER SECTION
AM Section
Band : AM
Volume : MIN
AM RF signal
generator
30% amplitude modulation by 400Hz
signal.
Output level : as low as possible
FM Section
Band : FM
Volume : MIN
FM RF signal
generator
0dB = 1µ V
Put the lead-wire
antenna close to
the set.
0.01
µ
F
TP102 (RF IN
MAIN board
• Repeat the procedures in each adjustment several times, and the
frequency coverage and tracking adjustments should be finally
done by the trimmer capacitors.
AM IF ADJUSTMENT
Adjust for a maximum reading on level meter.
T101 450kHz
AM FREQUENCY COVERAGE ADJUSTMENT
Adjust part Frequency display
L103 531kHz
Confirmation 1,710kHz 7.8 – 10.8V
AM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter.
L104 585kHz
CT101 1,485kHz
FM FREQUENCY COVERAGE CONFIRMATION
Adjust part Frequency display
Confirmation 76.0MHz 2.2 – 4.2V
Confirmation 108.0MHz 7.5 – 10.5V
reading on digital
voltmeter.
Adjustment Value : 2.5V
Standard Value : 2.45 – 2.55V
reading on digital
voltmeter.
22.5kHz frequency deviation by
400Hz signal.
Output level : as low as possible
set
Frequency Coverage Adjustment
Connect Location :
[MAIN BOARD] (SIDE B)
R533
D501
C314
RV201
R542
12
16
Q202
116
Q504
X501
C312
C201
ECB
IC301
BCE
C131
C127
R541
R603
C608
Q602
C605
R607
C207
BE
C206
C
C301
R201
C204
16
Ω
Headphone jack (J301)
R
Q201
R119
Q103
C121
C504
89
5
C307
1
R120
13152024
R
C308
R310
R309
CF102
C124
ECB
Q503
C311
C313
BCE
-1
C51
level mete
C310
106
+
–
D104
C17
C309
T101
C120
R533
100k
TP102
(RF IN)
FM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter.
L101 76.0MHz
CT102 108.0MHz
Digital
voltmete
Ω
– 5 –
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