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Ver 1.0 1999.10
MICROFILM
SRF-T615
SERVICE MANUAL
FM STEREO/AM PLL SYNTHESIZED RADIO
SPECIFICATIONS
Tourist Model


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­ 2 ­
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 dam-
aged by heat.
TABLE OF CONTENTS
SECTION 1
GENERAL
LOCATION AND FUNCTION OF CONTROLS
This section is extracted from
instruction manual.


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­ 3 ­
SECTION 2
DISASSEMBLY
Note : Follow the disassembly procedure in the numerical order given.
2-1. COVER (JOG) (A)
2-2. LID, BATTERY CASE
r
The equipment can be removed using the following procedure.
Cover (JOG) (A)
Set
Lid, Battery Case
Cabinet (Rear)
Main Board
1
Screw (B1.7x9)
2
Three claws
3
Turn from upper side
of the cover (JOG) (A),
and remove it.
Cover (JOG) (A)
3
Two claws
1
2
Lid, battery case


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­ 4 ­
2-3. CABINET (REAR)
2-4. MAIN BOARD
1
Screw (1.7x9)
2
Two claws
2
Two claws
2
Two claws
3
2
Claw
5
Button (MENU)
4
Knod (HOLD)
Cabinet (front) ASSY
Cabinet (rear)
1
Lead wire (Black)
3
Remove solder
Main board
2
Screws (1.4)
4
Terminal (+) (A), battery
Terminal (­) (A), battery
Cabinet (front) ASSY
Black
Brown


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­ 5 ­
TUNER SECTION
AM Section
Band : AM
Volume : MIN
FM Section
Band : FM
Volume : MIN
· 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
reading on digital
voltmeter.
L103
531kHz
Adjustment Value : 2.5V
Standard Value : 2.45 ­ 2.55V
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
reading on digital
voltmeter.
Confirmation
76.0MHz
2.2 ­ 4.2V
Confirmation
108.0MHz
7.5 ­ 10.5V
FM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter.
L101
76.0MHz
CT102
108.0MHz
SECTION 3
ADJUSTMENTS
AM RF signal
generator
30% amplitude modulation by 400Hz
signal.
Output level : as low as possible
Put the lead-wire
antenna close to
the set.
FM RF signal
generator
22.5kHz frequency deviation by
400Hz signal.
Output level : as low as possible
TP102 (RF IN)
MAIN board
0.01
µF
set
16
+
­
Headphone jack (J301)
level meter
0dB = 1
µ V
Frequency Coverage Adjustment
Connect Location :
R541
R603
R542
R533
C120
C608
D
C603
C605
X501
D501
D104
C311
C309
C310
C301
C314
Q201
CF102
13
15
20
24
T101
Q602
B
E
C
C127
C204
C131
C51
R119
R309
R310
R607
R201
R
116
R120
R
5
R
5
C124
C207
C313
C308
C307
C312
C201
C504
ECB
Q504
ECB
Q503
C17
BCE
BCE
Q202
C121
L
106
Q103
C206
1
5
8
9
12
16
IC301
RV201
-1
Digital
voltmeter
100k
TP102
(RF IN)
R533
[MAIN BOARD] (SIDE B)