Sony XR-C7200R User manual

MICROFILM
SERVICE MANUAL
FM/MW/LW CASSETTE CAR STEREO
AEP Model
UK Model
Model Name Using Similar Mechanism NEW
Tape Transport Mechanism Type MG-25D-136
SPECIFICATIONS
XR-C7200R
For RM-X2S (Remote Commander),
please refer to RM-X2S/X3S Service
Manual(9-960-039-∏)previously issued.
Dolby noise reduction manufactured under license
from Dolby Laboratories Licensing Corporation.
“DOLBY” and the double-D symbol aare trade-
marks of Dolby Laboratories Licensing Corporation.

– 2 –
TABLE OF CONTENTS
1. GENERAL
Location of Controls ....................................................... 3
Resetting the Unit ........................................................... 4
Detaching the Front Panel............................................... 4
Setting the Clock ............................................................. 4
Using the Rotary Commander ........................................ 5
Installation....................................................................... 6
Connections ..................................................................... 7
2. DISASSEMBLY ......................................................... 10
3. ASSEMBLY OF MECHANISM DECK........... 13
4. MECHANICAL ADJUSTMENTS ....................... 16
5. ELECTRICAL ADJUSTMENTS
Test Mode ........................................................................ 16
Tape Deck Section .......................................................... 16
Tuner Section .................................................................. 17
6. DIAGRAMS
6-1. IC Pin Function Description ........................................... 21
6-2. Printed Wiring Board – MAIN Section – ....................... 25
6-3. Schematic Diagram – MAIN Section –.......................... 29
6-4. Printed Wiring Boards – PANEL Section –.................... 33
6-5. Schematic Diagram – PANEL Section – ........................ 35
7. EXPLODED VIEWS................................................ 41
8. ELECTRICAL PARTS LIST ............................... 44
Flexible Circuit Board Repairing
• Keep the temperature of the soldering iron around 270 ˚C dur-
ing 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.

– 3 –
SECTION 1
GENERAL This section is extracted from
instruction manual.

– 4 –

– 5 –

– 6 –

– 7 –

– 8 –

– 9 –

– 10 –
COVER ASS’Y
FRONT PANEL ASS’Y
Note: Follow the disassembly procedure in the numerical order given.
SECTION 2
DISASSEMBLY
1 claw
3 cover ass’y
2 three claws
1 claw
4 front panel ass’y
3 Push the bearing (L).
2 Push the bearing (R).
1 Push the button (OPEN).

– 11 –
SUB PANEL ASS’Y
MECHANISM DECK (MG-25D-136)
5 claw
4 two claws
1 screw
(PTT2.6
× 8
)
6 sub panel ass’y
2 two screws
(PTT2.6
× 8)
3 two screws
(PTT2.6
× 8)
3 flexible flat cable
(
CN231
)
4 mechanism dec
k
(MG-25D-136)
1 two screws
(2.6
× 6)
2 connector
(CN201)

– 12 –
HEAT SINK
MAIN BOARD
5 screw
(PTT2.6 × 8)
1 three screws
(PTT2.6 × 8)
2 two screws
(PTT2.6 × 8)
3 three screws
(PTT2.6 × 8)
4 screw
(PTT2.6 × 8)
6 heat sink
4 insulator
3 main boar
d
1 ground point screw
2 two ground point screws

– 13 –
SECTION 3
ASSEMBLY OF MECHANISM DECK
HOUSING
ARM (SUCTION)
Note: Follow the assembly procedure in the numerical order given.
A part
C part
B part
D part
8 Hold the hanger by
bending the claw.
6 Fit projection on D part.
4 Fit claw on B part.
3 Put the housing
under A part.
5 Fit projection on C part.
1 Install the catch to the hanger.
2 Install the hanger onto
two claws of the housing.
7 Holder the hanger by bending the claw.
hanger
housing
2 Move the arm (suction) in the arrow
direction and fit on projection.
1 Fit the arm (suction) on the shaft.
projection

– 14 –
LEVER (LDG-A) / (LDG-B)
GEAR (LDG-FT)
shaft A
shaft B
shaft C
1
Fit the lever (LDG-A) on
shafts A – C and install it.
shaft A
shaft B
2
Fit the lever (LDG-B) on
shafts
A and B and
install it.
3 type-E stop ring 2.0
gear (LDG-D)
5 gear (LDG-FT)
6 polyethylene washer
2 tension spring (LD-2)
2 tension spring (LD-1)
gear (LDG-FB)
lever (LDG-A)
hole
hole
4 Align hole in the gear (LDG-D)
with hole the lever (LDG-A).
3 Move the lever (LDG-B)
in the arrow direction.
1

– 15 –
GUIDE (C)
2 guide (C)
1 three claws

– 16 –
SECTION 4
MECHANICAL ADJUSTMENTS
•TapeTension Measurement
1. Clean the following parts with a denatured-alcohol-moistened
swab:
playback head pinch roller
rubber belt capstan
idler
2. Demagnetize the playback head with a head demagnetizer.
3. Do not use a magnetized screwdriver for the adjustments.
4. After the adjustments, apply suitable locking compound to the
parts adjusted.
5. The adjustments should be performed with the power supply
voltage unless otherwise noted.
•Torque Measurement
SECTION 5
ELECTRICAL ADJUSTMENTS
Mode Tension Meter Meter Reading
Forward CQ-403A more than 90 g
(more than 3.18 oz)
Reverse CQ-403R more than 90 g
(more than 3.18 oz)
Mode Torque Meter Meter Reading
Forward CQ-102C 30 - 65 g•cm
(0.42 - 0.90 oz•inch)
Forward CQ-102C 0.5 - 4.5g•cm
Back Tension (0.01 - 0.06 oz•inch)
Reverse CQ-102RC 30 - 65 g•cm
(0.42 - 0.90 oz•inch)
Reverse CQ-102RC 0.5 - 4.5g•cm
Back Tension (0.01 - 0.06 oz•inch)
FF, REW CQ-201B 60 - 200 g•cm
(0.83 - 2.78 oz•inch)
TEST MODE
This set have the test mode function. In the test mode, FM Auto
Scan/Stop Level and MW Auto Scan/Stop Level adjustments can
be performed easier than it in ordinary procedure.
<Set the Test Mode>
1. Set the “power select” switch (S501) is “A (ON)” position.
2. Turn ON the regulated power supply. (All LEDs on the set
lights up, and the clock is displayed.)
Note: Press the [OFF] button, if the clock is not displayed.
3. Push the preset [4] button.
4. Push the preset [5] button.
5. Press the preset [1] button for more than two seconds.
6. Then the display indicates all lights, the test mode is set.
<Release the Test mode>
1. Push the [OFF] button.
2. Return the “power select” switch (S501) to initially set posi-
tion.
Tape Speed Adjustment
Setting:
Procedure:
1. Put the set into the FWD PB mode.
2. Adjust adjustment resistor for inside capstan motor so that the
reading on the speed checker or frequency counter becomes in
specification.
Specification: Constant speed
Adjustment Location: See page 20.
See the adjustment location from on page 20 for the
adjustment.
0 dB=0.775 V
TAPE DECK SECTION
set +–
test tape
WS-48A
(3 kHz, 0 dB)
speaker out terminal
4 Ω
speed checker
or
frequency counter
Speed checker Frequency counter
–1.5 to +2.5% 2,955 to 3,075 Hz

– 17 –
Dolby Level Adjustment
Setting:
[SHIFT] button : ON (light up SET UP and
PLAY MODE)
Preset [3] (PLAY MODE) button : NR off
SOUND (BAS) button : Center
SOUND (TRE) button : Center
SOUND (BAL) button : Center
SOUND (FAD) button : Center
SOUND (VOL) button : Maximum
Procedure:
1. Put the set into the FWD PB mode.
2. Adjust RV231 (L-CH) and RV241 (R-CH) so that the level
meter reading is –6±1 dB (0.35 to 0.44 V).
Adjustment Location: See page 20.
set +
–
test tape
P-4-D400
(400 Hz, 0 dB) level mete
r
MAIN board
TP (DOLBY-L)/
TP (DOLBY-R)
      
TUNER SECTION 0 dB=1 µV
Cautions during repair
When the tuner unit is defective, replace it by a new one be-
cause its internal block is difficult to repair.
Note: Adjust the tuner section in the sequence shown below.
1. FM Auto Scan/Stop Level Adjustment
2. FM Stereo Separation Adjustment
3. FM RDS S-Meter Adjustment
4. MW Auto Scan/Stop Level Adjustment
FM Auto Scan/Stop Level Adjustment
Setting:
[SOURCE] button: FM
Procedure:
1. Set to the test mode. (See page 16.)
2. Push the [SOURCE] button and set to FM.
Display
3. Adjust with the volume RV2 on TU10 so that the “FM” indi-
cation turns to “FM0” indication on the display window.
But, in case of already indicated “FM0”, turn the RV2 so that
put out light “0” indication and adjustment.
Display
Adjustment Location: See page 20.
set
antenna jack (J10)
FM RF signal
generator
Carrier frequency : 98.0 MHz
Output level : 22 dB (12.6
µ V)
Mode : mono
Modulation : 1 kHz, 22.5 kHz deviation (30%
)
0.01 µ F
REG SHUF1
REG SHUF1

– 18 –
FM Stereo Separation Adjustment
Setting:
[SOURCE] button: FM
Procedure:
L-CH Stereo separation: A-B
R-CH Stereo separation: C-D
The separations of both channels should be equal.
Specification: Separation more than 26 dB
Adjustment Location: See page 20.
FM Stereo Level meter Level meter
signal generator connection reading (dB)
output channel
L-CH L-CH A
B
R-CH L-CH Adjust RV4 on TU10
for minimum reading.
R-CH R-CH C
D
L-CH R-CH Adjust RV4 on TU10
for minimum reading.
FM RF signal
generator
Carrier frequency : 98.0 MHz
Output level : 70 dB (3.2 mV)
Mode : stereo
Modulation : main: 1 kHz, 20 kHz deviation (26.5%)
sub : 1 kHz, 20 kHz deviation (26.5%)
:19 kHz pilot: 7.5 kHz deviation (10%)
0.01 µ F
set
antenna jack (J10)
+
–
speaker out terminal
level meter
4
Ω
FM RDS S-Meter Adjustment
Setting :
[SOURCE] button: FM
Procedure :
1. Set to the test mode. (See page 16.)
2. Push the [SOURCE] button and set to FM.
Display
3. Push the preset [10] button.
4. Adjust RV110 on MAIN board so that the display indication
is “16.0”. Display
Specification : Display indication : 15.8 to 16.2.
Adjustment Location : See page 20.
set
antenna jack (J10)
FM RF signal
generator
Carrier frequency : 98.00 MHz
Output level : 35 dB (56.2
µ V)
Mode : mono
Modulation : no modulation
0.01
µ F
REG SHUF1
REG SHUF1

– 19 –
MW Auto Scan/Stop Level Adjustment
Setting:
[SOURCE] →[MODE] button: MW
Procedure:
1. Set to the test mode. (See page 16.)
2. Push the [SOURCE] button and set to FM.
3. Push the [MODE] button and set to MW.
Display
4. Adjust with the volume RV1 onTU10 so that the “MW” indi-
cation turns to “MW0” indication on the display window.
But, in case of already indicated “MW0”, turn the RV1 so that
put out light “0” indication and adjustment.
Display
Adjustment Location: See page 20.
REG
TP
SHUF1
REG
TP
SHUF1
AM RF signal
generator
Carrier frequency : 999 kHz
30% amplitude
modulation by
1 kHz signal
Output level : 33 dB (44.7
µ
V)
(50 Ω )set
AM dummy antenna
30 Ω
15 pF
65 pF
antenna jack (J10)

– 20 –
Adjustment Location:
R-CH
L-CH TP (DOLBY)
Dolby Level
Adjustment
– SET BOTTOM VIEW –
TU10
Tape Speed Adjustment
– SET UPPER VIEW –
RV1 MW Auto Scan/Stop Level Adjustmen
t
RV4 FM Stereo Separation Adjustment
RV2 FM Auto Scan/Stop Level Adjustment
RV241
(R-CH) RV231 (L-CH)
Dolby Level
Adjustment
RV110 FM RDS S-Meter Adjustment