Sony TC-TX77 User manual

MICROFILM
TC-TX77
STEREO CASSETTE DECK
SERVICE MANUAL
AEP Model
UK Model
Model Name Using Similar Mechanism TC-S1
Tape Transport Mechanism Type TCM-9700HLD
SPECIFICATIONS
Dolby noise reduction manufactured under license
from Dolby Laboratories Licensing Corporation.
“DOLBY”andthedouble-Dsymbolaaretrademarks
of Dolby Laboratories Licensing Corporation.

– 2 –
TABLE OF CONTENTS
1. GENERAL ................................................................... 3
2. DISASSEMBLY.......................................................... 4
3. MECHANICAL ADJUSTMENTS ....................... 7
4. ELECTRICAL ADJUSTMENTS ......................... 7
5. DIAGRAMS
5-1. IC Pin Function Description ............................................ 11
5-2. Printed Wiring Boards ..................................................... 13
5-3. Schematic Diagram ......................................................... 17
6. EXPLODED VIEWS ................................................ 23
7. ELECTRICAL PARTS LIST................................ 28
SAFETY-RELATED COMPONENT WARNING!!
COMPONENTS IDENTIFIED BY MARK !OR DOTTED
LINE WITH MARK !ON THE SCHEMATIC DIAGRAMS
AND IN THE PARTS LIST ARE CRITICAL TO SAFE
OPERATION. REPLACE THESE COMPONENTS WITH
SONY PARTS WHOSE PART NUMBERS APPEAR AS
SHOWN IN THIS MANUAL OR IN SUPPLEMENTS PUB-
LISHED BY SONY.

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

– 4 –
SECTION 2
DISASSEMBLY
•This set can be disassembled in the order shown below.
2
Note: Follow the disassembly procedure in the numerical order given.
COVER, FRONT PANEL SECTION
AUDIO/CONNECTOR BOARD, POWER TRANSFORMER (T901)
(Page 5)
TRAY (A) ASS’Y
(Page 6)
COVER, FRONT PANEL SECTION
(Page 4) MECHANISM DECK (TCM-9700HLD) (page 5) MOTOR (HK) ASS’Y (M902) (Page 6)
1 two screws
(CASE 3 TP2)
3 wire (flat type) (5 core)
(CN301)
4 two screws
(BVTP3
× 8)
1 two screws
(CASE 3 TP2)
8 LID (R-TC)
7 two claws
3 wire (flat type)
(27 core) (CN802)
6 front panel section
5 three claws
4 two screws
(BVTP3
× 8)
2 Remove the cover to
direction of the arrow.

– 5 –
MECHANISM DECK (TCM-9700HLD)
AUDIO/CONNECTOR BOARD, POWER TRANSFORMER (T901)
4 lag
5 mechanism deck
(TCM-9700HLD)
1 connector
(CN351)
2 two screws
(BVTP3
× 8)
1 connector
(CN803)
1 connector
(CN804)
3 two screws
(BVTP3
× 8)
6 power thansformer
(T901)
8 connector board
!º four screws
(BVTP3
× 8)
9 screw
(BVTP3
× 10)
!¡ audio board
3 wire (flat type) (15 core)
(CN711)
2 connector
(CN351)
1 power cord
(CN901)
5 connector
(CN701)
7 two connectors
(CN713, 715)
4 four screws
(BVTT3
× 6)

– 6 –
TRAY (A) ASS’Y
MOTOR (HK) ASS’Y (M902)
2 two claws
A
tray
3 tray (A) ass’y
tray (A) ass’y
1 Rotate the gear ass’y in direction
arrow
A to up the tray.
1 six screws
(BVTT2.6
× 8)
5 three step screws
(MOTOR)
6 motor (HK) ass’y
(M902)
3 Remove the belt to position
figure the hang.
2 mechanism deck
4 Remove the solders
of motor (M902).

– 7 –
SECTION 3
MECHANICAL ADJUSTMENTS SECTION 4
ELECTRICAL ADJUSTMENTS
PRECAUTION
1. Clean the following parts with a denatured-alcohol-moistened
swab:record/playback/earth head pinch roller
rubber belts capstan
idlers
2. Demagnetize the record/playback head with a head demagne-
tizer. (Do not bring the head demagnetizer close to the erase
head.)
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 rated power
supply voltage unless otherwise noted.
Torque Measurement
PRECAUTION
1. The adjustment should be performed in the publication.
(Be sure to male playback adjustment at first.)
2. The adjustments and measurement should be performed for
both L-CH and R-CH.
•Switch position
DOLBY NR switch : OFF
DIRECTION switch : A
•Standard record position
Deliver the standard input signal level to input jack and set
the REC LEVEL (RV301) control to obtain the standard
output signal level as follows.
– Record Mode –
set
AF OSC
attenuator
600
Ω
10 k Ω
LINE IN
+
–
LINE OUT
47 k
Ω
level meter
Standard Input Level
Input terminal LINE IN
source impedance 10 kΩ
input signal level 0.5 V (– 3.8 dB)
Standard Output Level
Output terminal LINE OUT (L-CH)
load impedance 47 kΩ
output signal level 0.5 V (– 3.8 dB)
TestTape
Type Signal Used for
P-4-A100 10 kHz, – 10 dB Azimuth Adjustment
P-4-L300 315 Hz, 0 dB PB Level Adjustment
WS-48B 3 kHz, 0 dB Tape Speed Adjustment
0 dB = 0.775 V
Mode Torque Meter Meter Reading
CQ-102C
30 – 65 g•cm
FWD (0.42 – 0.90 oz•inch)
FWD 1.5 – 6 g•cm
Back tension (0.021 – 0.083 oz•inch)
CQ-102RC
30 – 65 g•cm
REV (0.42 – 0.90 oz•inch)
REV 1.5 – 6 g•cm
Back tension (0.021 – 0.083 oz•inch)
70 – 130 g•cm
FF, REW CQ-201B (0.98 – 1.80 oz•inch)
Test Mode
With the POWER turned OFF, short the test point CN801 (2P) on
the SYSTEM CONTROL board (making IC801 pin !º “L”) and
turn the POWER ON. Thus, the TEST mode will be activated.
If a recording is done in the TEST mode, the REC MEMORY
mode becomes active where the tape is rewound by the amount of
recording when a rewinding is executed after recording.
After adjustment, make the CN801 (2P) open to release the TEST
mode.

– 8 –
Record/Playback Head Azimuth Adjustment
Procedure:
1. Mode: REV playback
+
–
set
47 k
Ω
LINE OUT
level mete
r
test tape
P-4-A100
(10 kHz, – 10 dB)
2. Turn the adjustment screw for the maximum output levels. If
these levels do not match, turn the adjustment screw until both
of output levels match together within 1 dB.
Tape Speed Adjustment
Procedure:
Mode: FWD playback
+
–
set
LINE OUT
frequency counte
r
test tape
WS-48B
(3 kHz, 0 dB) 47 k
Ω
1. Set to FWD playback mode.
2. Adjust RV801 so that the frequency counter reading becomes
3,000 ± 90 Hz.
3. Confirm that the deviation between tape top and tape end is
within 3%.
Adjustment Location: SYSTEM CONTROL board (See page 10)
Sample Value of Wow and flutter: 0.3% or less W.RMS
(WS-48B)
Playback Level Adjustment
Procedure:
Mode: FWD playback
Screw
position
L-CH
peak
within
1dB
output
level
L-CH peak R-CH peak
within
1dB
angl
e
R-CH
peak
3. Phase Check
Mode: REV playback
+
–
VH
+
–
Screen pattern
Good Wrong
in phase 45
° 90 ° 135 ° 180 °
LINE OUT
set
R-CH
L-CH 47 k
Ω
47 k Ω
oscilloscope
test tape
P-4-A100
(10 kHz, –10 dB)
4. Set in the FWD mode and repeat the step 1 to 3.
5. After the adjustment, lock the screw with locking compound.
Adjustment Location: Record/Playback head
              
FWD side REV side
Adjustment screw
+
–
set
LINE OUT
47 k
Ω
test tape
P-4-L300
(315 Hz, 0 dB) level mete
r
Adjust RV151 (L-CH) and RV251 (R-CH) so that the reading on
level meter meets the adjustment limits below.
Adjustment Limits:
LINE OUT level: – 7.7 ± 0.5 dB (0.301 to 0.338 V)
Level difference between channels: within 2 dB
Check that the LINE OUT level does not change even if Playback
and Stop operation is repeated several times.
Adjustment Location: AUDIO board (See page 10)

– 9 –
Record BIAS Adjustment
Setting:
REC LEVEL control: Standard record position (See page 7)
Set to the TEST mode (REC MEMORY mode). (See page 7)
Procedure:
1. Mode: Record
Record Level Adjustment
Setting:
REC LEVEL control: Standard record position (See page 7)
Set to the TEST mode (REC MEMORY mode). (See page 7)
Procedure:
1. Mode : Record
set
AF OSC
attenuator
600
Ω
10 k Ω
blank tape
CS-123
LINE IN
1) 315 Hz
2) 10 kHz 50 mV (– 23.8 dB)
set
AF OSC
attenuator
600
Ω
10 k Ω
blank tape
CS-123
LINE IN
315 Hz, 50 mV (– 23.8 dB)
2. Mode: Playback
+
–
set
LINE OUT
47 k
Ω
recorded portion level mete
r
3. Confirm playback the signal recorded in step 1 become ad-
justment level as follows.
4. If these levels do not adjustment level, adjust the RV152 (L-
CH) and RV252 (R-CH) to repeat step 1 and 2.
Adjustment Level: Playback output of 10 kHz to playback
output of 315 Hz: ± 0.5 dB.
Adjustment Location: AUDIO board (See page 10)
2. Mode: Playback
+
–
set
LINE OUT
47 k
Ω
recorded portion level mete
r
3. Confirm playback the signal recorded in step 1 become ad-
justment level as follows.
4. If these levels do not adjustment level, adjust RV153 (L-CH)
and RV253 (R-CH) to repeat step 1 and 2.
Adjustment Level: – 23.8 ± 0.5 dB (47 to 53 mV)
Adjustment Location: AUDIO board (See page 10)

– 10 –
• Adjustment Parts Location
[AUDIO BOARD] (Component Side)
[SYSTEM CONTROL BOARD] (Component Side)
CN714
CN711
IC304
CN351
RV151
Playback Level (L-CH)
RV251
Playback Level (R-CH)
RV252
Record Bias (R-CH)
RV152
Record Bias (L-CH)
RV153
Record Level (L-CH)
IC301
RV253
Record Level (R-CH)
CN803
IC803
CN801
TEST Mode
RV801
Tape Speed

– 11 –
1 METER-R I Digital peak level meter signal input (R-ch)
2 METER-L I Digital peak level meter signal input (L-ch)
3 KEY-Y I Key input (A/D convert input) *1
4 KEY-X I
5 FWD-TAB I Record proof detection input from S902 (FWD side) “H”: Not nail
6 CHROM SW I Tape type detection input from S903 “L”: Type I
7 RVS-TAB I Record proof detection input from S904 (REV side) “H”: Not nail
8 METAL SW I Metal cassette detection input from S906
9 PLAY SW I Playback and stop detection input from S907 “L”: Playback
10 TEST MODE I Test mode terminal Normal: “H” Test mode: “L”
11 POWER OUT O Audio and mechanism power on/off output “L”: Off
12 POWER DET I Primary power on/off input “H”: On
13 CLOSE O Loading motor (M901) drive output *2
14 OPEN O
15 — —
16 — —
17 — — Not used (Fixed at “L”)
18 — —
19 — —
20 — —
21 CLOCK O Clock signal output to back-up memory (IC803)
22 DATA I/O Data signal input/output to back-up memory (IC803)
23 RELAY O Relay drive output “L”: On
24 BIAS O Control output to recording bias switch (Q352) “L”: On
25 AU BUS-OUT O Audio bus output
26 AU BUS-IN I Audio bus input
27 RESET I Reset input
28 X CIN I Not used (Fixed at “L”)
29 X COUT O Not used (Open)
30 X IN I Main system clock input (4 MHz)
31 XOUT O Main system clock output (4 MHz)
32 Vss — Ground
33 REC MUTE O Recording mute on/off control output “L”: Mute on
34 LINE MUTE O Line mute on/off control output “L”: Mute on
35 — — Not used (Fixed at “L”)
36 PB MUTE O Playback mute on/off control output “L”: Mute on
37 REC/PB O Mode control output to DOLBY NR amplifier (IC301) When recording: “L”
38 DOLBY B/C O DOLBY B/C select signal output “L”: DOLBY C, “H”: DOLBY B
39 DOLBY ON/OFF O DOLBY on/off select signal output “L”: DOLBY On, “H”: DOLBY Off
40 — — Not used (Open)
41 — — Not used (Open)
42 — — Not used (Open)
43 CD SYNC O Control output to CD SYNC LED (D851)
44 P17 O
45 P16 O Segment signal output to fluorescent indicator tube (FLT851)
46 P15 O
5-1. IC PIN FUNCTION DESCRIPTION
SYSTEM CONTROL BOARD IC801 M38172M4-150FP (SYSTEM CONTROL)
Pin No. Pin Name I/O Function
SECTION 5
DIAGRAMS

– 12 –
Pin No. Pin Name I/O Function
47 P14 O
48 P13 O
49 P12 O
50 P11 O
51 P10 O
52 P9 O
53 P7 O Segment signal output to fluorescent indicator tube (FLT851)
54 P6 O
55 P5 O
56 P4 O
57 P3 O
58 P2 O
59 P1 O
60 G5 O
61 G4 O
62 G3 O Grid Signal output to fluorescent indicator tube (FLT851)
63 G2 O
64 G1 O
65 TYPE 1 O Tape type output “H”: Normal position
66 TYPE 2 O Tape type output “H”: High position
67 TYPE 4 O Tape type output “H”: Metal position
68 — —
69 — — Not used (Fixed at “L”)
70 — —
71 SOLENOID O Plunger (PM901) drive output “H”: On
72 CAPSTAN O Capstan/reel motor (M902) drive output “H”: On
73 Vcc — Power supply (+5 V)
74 Vee — Ground
75 AVss — Ground for A/D converter
76 Vref I Reference voltage (+5 V) for A/D converter
77 HALF I Cassette half detection input from S905
78 AMS IN I AMS input
79 LIMIT SW I Loading detection input from S901 Open: “L”, Close: “M”, COM: “H”
80 PULSE I Rotary detection input from PH901
Voltage
Input port 0 V 0.45 V 1.19 V 2.19 V 3.2 V 3.98 V 4.48 V 5.0 V
Pin 4, KEY-X Open/Close STOP PAUSE FWD REV CD —Not key input
§p P·ªSYNC
Pin 3, KEY-Y POWER REW FF REC RESET DIRECTION DOLBY NR Not key input
ON/OFF 0) r
*1 Key Input
*2 Loading Motor (M901)
IN OUT BRAKE
CLOSE !£ HLH
OPEN !¢ LHH

– 23 –
NOTE:
•-XX and -X mean standardized parts, so they
may have some difference from the original
one.
•Color Indication of Appearance Parts
Example:
KNOB, BALANCE (WHITE) . . . (RED)
↑↑
Parts Color Cabinet's Color
•Items marked “*” are not stocked since they
are seldom required for routine service. Some
delay should be anticipated when ordering
these items.
•The mechanical parts with no reference num-
ber in the exploded views are not supplied.
•Hardware (# mark) list and accessories and
packing materials are given in the last of the
electrical parts list.
SECTION 6
EXPLODED VIEWS
The components identified by mark
!or dotted line with mark !are
critical for safety.
Replace only with part number
specified.
(1) COVER, FRONT PANEL SECTION
Ref. No. Part No. Description Remark Ref. No. Part No. Description Remark
1 4-985-926-01 KNOB
2 X-3372-679-1 PANEL ASSY, FRONT
3 4-962-708-01 EMBLEM (4-A), SONY
4 3-939-648-01 WINDOW (TC)
5 3-939-646-01 BUTTON (REC) (CD SYNC. rREC)
6 3-939-645-01 BUTTON (POWER)
7 3-939-647-01 INDICATOR (TC)
8 4-951-620-01 SCREW (2.6X8), +BVTP
9 3-939-653-01 LID (R-TC)
10 3-363-099-01 SCREW (CASE 3 TP2)
*11 3-939-652-11 COVER
*12 A-2007-717-A PANEL BOARD, COMPLETE
13 3-939-643-01 BUTTON (FF) (0. ))
14 3-939-642-01 BUTTON (PLAY) (ª. ·. P. p)
15 3-939-644-01 BUTTON (EJECT) (§. OPEN/CLOSE)
4
not supplied
5
78
9
10
13
15
#1
#1
1
2
3
14
12
not
supplied
8
6
11
10

– 24 –
(2) CHASSIS SECTION
51 4-977-699-11 LEG (F)
*52 A-2007-716-A SYSTEM CONTROL BOARD, COMPLETE
53 1-773-247-11 WIRE (FLAT TYPE) (27 CORE)
*54 1-663-308-11 TRANS BOARD
*55 1-663-310-11 PRIMARY BOARD
*56 3-939-651-11 PANEL, BACK
!57 1-575-651-21 CORD, POWER (AEP)
!57 1-696-571-21 CORD, POWER (UK)
*58 3-703-244-00 BUSHING (2104), CORD
59 1-696-981-11 WIRE (FLAT TYPE) (5 CORE)
60 1-773-009-11 WIRE (FLAT TYPE) (15 CORE)
*61 1-663-309-11 CONNECTOR BOARD
*62 A-2007-715-A AUDIO BOARD, COMPLETE
63 4-965-822-01 FOOT
*64 3-350-847-21 HOLDER, PCB
!T901 1-431-302-11 TRANSFORMER, POWER
Ref. No. Part No. Description Remark Ref. No. Part No. Description Remark
The components identified by mark
!or dotted line with mark !are
critical for safety.
Replace only with part number
specified.
#1
not supplied
63
62
#2
58
57
57
56
55
54
not supplied
61
60
59
TCM-9700HLD
T901
AEP
UK
#2
#1
#8
64
#2
51
64
not supplied
64
52
#1
53
#1

– 25 –
(3) MECHANISM DECK SECTION-1
(TCM-9700HLD)
not
supplied
103 104
105
106
107
108109
106
110
111
101
102
#4
#3
S901
M901
Ref. No. Part No. Description Remark Ref. No. Part No. Description Remark
101 A-2004-430-A TRAY (A) ASSY
102 A-2004-429-A CLAMP (B) ASSY
103 3-917-502-01 SCREW (2X8), +BTT
104 3-917-501-01 SPRING, TOGGLE
105 3-917-498-01 SCREW (2.6X6), +BTT
106 3-917-497-01 SCREW (2.6X5), +BTT
107 3-917-499-01 BELT
108 X-3369-090-1 GEAR ASSY
109 3-918-629-01 SPRING (A), COMPRESSION
110 3-918-630-01 WASHER, FLAT
111 3-917-496-01 CHASSIS (MAIN)
M901 X-3369-091-1 MOTOR ASSY (LOADING)
S901 1-762-989-11 SWITCH, ROTARY (LOADING DET)

– 26 –
(4) MECHANISM DECK SECTION-2
(TCM-9700HLD) 170
169
168167
166
165
164
163
162
174
162
176
177
not supplied
not supplied
178
155
180
181
not supplied
not supplied
185
#5
186
PM901
#5
#6
151
152
153
#6
#6
not
supplied
154
not supplied
not supplied
158
159
155
157
156
155 160 161
HRPE901
155
165
173
172
171
179
183
184
182
Ref. No. Part No. Description Remark Ref. No. Part No. Description Remark
151 A-2004-436-A GEAR ASSY, PLAY
152 3-917-549-01 ARM, PLAY
153 3-917-553-01 SPRING (PLAY ARM), TOGGLE
154 3-917-566-01 SCREW (2X6), +PTT
155 3-917-565-01 SCREW (2X4), +PTT
156 3-917-558-01 WASHER, POLY-SLIDER
157 3-917-561-01 WASHER, NYLON
158 3-917-556-01 SPRING (P ROLLER ARM R), TOGGLE
159 A-2004-434-A ARM (R) ASSY, P ROLLER
160 3-917-533-01 SCREW (HEAD RVS)
161 3-917-532-01 CLAMP, HEAD WIRE
162 3-917-537-01 SPRING (TAPE GUIDE), COMPRESSION
163 3-917-539-01 GUIDE (R), TAPE
164 3-917-524-01 SPRING (AZIMUTH)
165 3-917-541-01 SCREW (2X5)
166 3-917-531-01 SCREW (AZIMUTH)
167 3-917-528-01 GEAR (RETURN)
168 3-917-526-01 COLLAR
169 3-917-536-01 SCREW (POWER LOCK)
170 3-917-530-01 SPRING (RETURN), TOGGLE
171 3-917-534-01 WASHER, POLY-SLIDER
172 3-917-527-01 GEAR (ROTATION)
173 3-917-540-01 WASHER, POLY-SLIDER
174 3-917-538-01 GUIDE (L), TAPE
176 3-917-529-01 GUIDE (CASSETTE)
177 X-3369-095-1 PLATE ASSY, HEAD
178 A-2004-435-A ARM (L) ASSY, P ROLLER
179 3-917-557-01 SPRING (P ROLLER ARM L), TOGGLE
180 3-917-562-01 WASHER, NYLON
181 3-917-559-01 WASHER, POLY-SLIDER
182 3-917-555-01 SPRING (HEAD CHASSIS H), TOGGLE
183 3-917-554-01 SPRING (SHIFT H), TOGGLE
184 3-917-550-01 ARM, SELECT
185 3-917-547-01 LEVER, SHIFT
186 3-917-568-01 WASHER, POLY-SLIDER
HRPE9011-500-156-11 HEAD (RECORD) (REC/PB/ERASE)
PM901 3-917-560-01 SOLENOID

– 27 –
(5) MECHANISM DECK SECTION-3
(TCM-9700HLD) 217218
210
211
212
213
214
213
215
216
not
supplied
M902
219
not
supplied
#5
#5
#7
223
222
221
220
225
228
230
229
227
226
231
221
232
233
220
234
236
235
237
#6
not supplied
202
203
204
205
206
203
207
208
209
215
211
212
not
supplied
219
224
221
201
Ref. No. Part No. Description Remark Ref. No. Part No. Description Remark
201 3-917-608-01 BELT (HK-3), DRIVE
202 X-3369-099-1 CLUTCH (HK) ASSY
203 3-917-599-01 WASHER, POLY-SLIDER
*204 X-3369-098-1 BASE (HK) ASSY, MECHANICAL
205 3-917-580-01 SPRING (PACK KH)
206 3-917-582-01 GEAR, REW
207 3-917-581-01 GEAR, CLUTCH
208 3-917-584-01 GEAR, FR
209 3-917-583-01 ARM, FR
210 3-917-587-01 BUSHING (B), REEL
211 3-917-586-01 CAP (A), REEL
212 3-917-594-01 SPRING (REEL C), COMPRESSION
213 3-917-585-01 GEAR, REEL
214 3-917-600-01 SEAL, REFLECT
215 3-917-602-01 FELT, REEL
216 3-917-589-01 GEAR, PLAY CAM
217 3-917-590-01 ARM, TRIGGER
218 3-917-597-01 SPRING (TRIGGER ARM), TENSION
219 3-917-565-01 SCREW (2X4), +PTT
220 3-917-604-01 WASHER, POLY-SLIDER
221 3-701-437-11 WASHER
222 3-917-623-01 CUSHION, MOTOR RUBBER
223 3-917-622-01 WASHER (B), FLAT
224 3-917-620-01 SCREW (MOTOR), STEP
225 3-917-588-01 SELECT, SHIFT LEVER
226 3-917-601-01 WASHER, POLY-SLIDER
227 3-917-592-01 FLYWHEEL (RD) (HK) ASSY
228 3-917-593-01 FLYWHEEL (LD) (HK) ASSY
229 3-917-606-01 BELT (HK-1), DRIVE
230 3-917-607-01 BELT (HK-2), DRIVE
231 3-917-596-01 SPRING, TOGGLE
232 3-917-603-01 PULLEY (FLYWHEEL C) ASSY
233 3-917-605-01 WASHER, NYLON
234 3-917-595-01 SPRING (CLUTCH ARM), TOGGLE
*235 1-653-898-11 MECH BOARD
236 3-917-598-01 SPRING (BRAKE ARM), TOGGLE
237 3-917-591-01 ARM, BRAKE
M902 X-3369-100-1 MOTOR (HK) ASSY (CAPSTAN/REEL)
#5
208
not
supplied