Sony HST-471 User manual

HST-471
AEP Model
UK Model
E Model
Australian Model
SERVICE MANUAL
CASSETTE DECK RECEIVER
MICROFILM
Tape deck Model Name Using Similar Mechanism HCD-GR8/RX90
Section Tape Transport Mechanism Type TCM-220WR2
SPECIFICATIONS
Manufactured under license from Dolby
Laboratories Licensing Corporation.
“DOLBY” and the double-D symbol aare
trademarks of Dolby Laboratories Licensing
Corporation.
— Continued on next page —
This set is the tunerdeck
and amplifier section
in SEN-R4720/R5750.

— 2 —
TABLE OF CONTENTS
SAFETY-RELATED COMPONENT WARNING!!
COMPONENTS IDENTIFIED BY MARK !OR DOTTED LINEWITH
MARK !ON THE SCHEMATIC DIAGRAMS AND INTHE 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
PUBLISHED BY SONY.
ATTENTION AU COMPOSANT AYANT RAPPORT
MODEL IDENTFICATION
— Model Number Label —
AEP, UK : AC 220-230V ~ 50/60Hz 240W
Australian : AC 240V ~ 50Hz 240W
E, Singapore : AC 110-120, 220-240V selectable ~ 50/60Hz 240W
MODEL IDENTIFICATION
MODEL NO. HST-471
CASSETTE DECK RECEIVER
1. GENERAL
• Tuner/Amp Section ···································································· 3
• Deck Section ·············································································· 3
2. MECHANICAL ADJUSTMENTS ·························· 4
3. ELECTRICAL ADJUSTMENTS ···························· 4
4. DIAGRAMS
4-1. Circuit Boards Location ····················································· 8
4-2. Block Diagram ··································································· 9
4-3. Schematic Diagram — Deck Section — ·························· 12
4-4. Printed Wiring Board — Deck Section — ······················· 15
4-5. Printed Wiring Board — Main Section — ······················· 17
4-6. Schematic Diagram — Main Section — ·························· 19
4-7. Schematic Diagram — Display Section — ······················ 23
4-8. Printed Wiring Board — Display Section — ··················· 27
4-9. Printed Wiring Board — Power Section — ····················· 30
4-10. Schematic Diagram — Power Section — ························ 33
4-11. IC Block Diagrams ··························································· 36
4-12. IC Pin Function ································································ 38
5. REPAIR PARTS LIST
5-1. Main Section····································································· 40
5-2. Front Panel Section ·························································· 41
5-3. Tape Mechanism Deck Section-1
(TCM-220WR2) ······························································· 42
5-4. Tapa Mechanism Deck Section-2
(TCM-220WR2) ······························································· 43
6. ELECTRICAL PARTS LIST ··································· 44

— 3 —
SECTION 1
GENERAL
•TUNER/AMP SECTION
110 KEY
2MEMORY
3TUNING (–/+)
4BAND
5MEMORY SCAN
6STEREO/MONO
7POWER
8CENTER MODE
9SURROUND MODE (DOLBY/HALL/SIMULATED)
!º CONTROL MODE (–/+)
!¡ CONTROL MODE
(TONE/CENTER/REAR/WOOFER)
!™ MASTER VOLUME
!£ WOOFER ON/OFF
!¢ VIDEO 1/VIDEO 2/TAPE/CD/TUNER/PHONO
!∞ SOUND FIELD
(1 ROCK/2 POPS/3 CLASSIC/4 MOVIE/5 GAME)
• DECK SECTION
!§ 0(DECK A)
!¶ )(DECK A)
!• p(DECK A)
!ª ª(DECK A)
@º ·(DECK A)
@¡ DIRECTION (DECK B)
@™ DOLBY NR (DECK B)
@£ DUBBING SPEED (HIGH/NORMAL) (DECK B)
@¢ REC (PAUSE/REC MUTE/REC) (DECK B)
@∞ 0(DECK B)
@§ p(DECK B)
@¶ ª(DECK B)
@• ·(DECK B)
@ª )(DECK B)

— 4 —
SECTION 2
MECHANICAL ADJUSTMENTS SECTION 3 ELECTRICAL ADJUSTMENTS
PRECAUTION
1. Clean the following parts with a denatured-alcohol-moistened
swab:record/playback head pinch roller
erase head rubber belts
capstan idlers
2. Demagnetize the record/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 rated power
supply voltage unless otherwise noted.
•Torque Measurement
•TapeTension Measurement
DECK SECTION 0 dB=0.775V
1. Demagnetize the record/playback head with a head
demagnetizer. (Do not bring the head demagnetizer close to
the erase head.)
2. Do not use a magnetized screwdriver for the adjustments.
3. After the adjustments, apply suitable locking compound to the
parts adjust.
4. The adjustments should be performed with the rated power
supply voltage unless otherwise noted.
5. The adjustments should be performed in the order given in this
servicemanual. (Asageneral rule,playback circuitadjustment
should be completed before performing recording circuit
adjustment.)
6. The adjustments should be performed for both L-CH and R-
ch.
7. Switchesand controlsshould beset asfollows unlessotherwise
specified.
8. Set to test mode. (Press key switch same time
SPECTRUM ANALYZER ENTER/NEXT and
EFFECT ON/OFF button.)
• Test Tape
Record/Playback Head Azimuth Adjustment
DECK A DECK B
Note : Perform this adjustments for both decks. Remove the covers
of cassette holders.
Procedure:
1. Mode: Playback (FWD)
Mode Torque Meter Meter Reading
Forward CQ-102C 36 to 61g•cm
(0.50 – 0.84 oz•inch)
Forward CQ-102C 2 to 6g•cm
Back Tension (0.026 – 0.082 oz•inch)
Reverse CQ-102RC 36 to 61g•cm
(0.50 – 0.84 oz•inch)
Reverse CQ-102RC 2 to 6g•cm
Back Tension (0.026 – 0.082 oz•inch)
FF, REW CQ-201B 61 to 143g•cm
(0.85 – 1.98 oz•inch)
Mode Tension Meter Meter Reading
Forward CQ-403A more than 100 g (3.53 oz)
Reverse CQ-403R more than 100 g (3.53 oz)
Tape Signal Used for
P-4-A100 10 kHz, –10 dB Azimuth Adjustment
WS-48B 3 kHz, 0dB Tape Speed Adjustment
P-4-L300 315 Hz, 0dB Level Adjustment
set
rear panel
VIDEO1
AUDIO OUT connector
(L: L-CH)
(R: R-CH)
+
–
level meter
test tape
P-4-A100
(10 kHz, –10 dB)

— 5 —
2. Turn the adjustment screw and checkoutput peaks. If the peaks
do not match for L-CH and R-CH, turn the adjustment screw
so that outputs match within 1dB of peak.
3. Mode: Playback (FWD)
4. Repeat steps 1 to 3 in playback (REV) mode.
5. After the adjustments, apply suitable locking compound to the
pats adjusted.
Adjustment Location: Record/Playback Head (Deck A and B)
and main board.
reverse
forward
Tape Speed Adjustment DECK A
Note: Start the Tape Speed adjustment as below after setting to the
test mode.
Procedure:
Mode: Playback (FWD)
1. Insert the WS-48B into the deck A and the blank tape into the
deck B.
2. Press the REC button and ·button on the deck B. Then
the deck B is at recording mode.
3. Set the deckA to playback mode.
4. Press the DUBBING SPEED HIGH button in playback mode.
Then at HIGH speed mode.
5. Adjust RV652 on the AUDIO board do that frequency counter
reads 6,000 ± 90 Hz.
6. Press the DUBBING SPEED NORMAL button in playback
mode.
Then at NORMAL speed mode.
7. Adjust RV651 on theAUDIO board so that frequency counter
reads 3,000 ± 90Hz.
8. FrequencydifferencebetweendeckAanddeck Bthe beginning
of the tape should be within ± 1.5 %.
Adjustment Location: AUDIO board
Sample Value of Wow and flutter
W.RMS (JIS) within 0.3%
(test tape: WS-48B)
Playback level Adjustment DECK A DECK B
Procedure:
Mode: Playback (FWD)
Deck A is RV311 (L-CH) and RV411 (R-CH), Deck B is RV301
(L-CH) and RV401 (R-CH) so that adjustment within adjustment
level as follows.
Adjustment Level:
VIDEO1 AUDIO OUT PB level: 301.5 to 338.3 mV (–8.2 to
–7.2 dB) level difference between the channels: within ± 0.5
dB
Adjustment Location: AUDIO and main boards
Screw
position
L-CH
peak
within
1dB
output
level
L-CH
peak R-CH
peak
within
1dB
Screw
position
R-CH
peak
set
test tape
P-4-A100
(10kHz, –10dB) oscilloscope
L
R
V
waveform of oscilloscope
in phase 45 ° 90 ° 135 ° 180 °
good wrong
rear panel
VIDEO1
AUDIO OUT connector
H
+
–
set
test tape
WS-48B
(3 kHz, 0 dB) frequency counter
rear panel
VIDEO1
AUDIO OUT connector
(L: L-CH)
(R: R-CH)
+
–
level mete
r
set
test tape
P-4-L300
(315 Hz, 0 dB) rear panel
VIDEO1
AUDIO OUT connector
(L: L-CH)
(
R: R-CH
)

— 6 —
Record bias Current Adjustment DECK B
Procedure:
1. Mode: Record
2. Mode: Playback
Confirm playback the signal recorded in step 1 become adjustable
limits as follows.
If these levels do not adjustable limits, adjustment the RV341 (L-
CH) and RV441 (R-CH) on the AUDIO board to repeat steps 1 and 2.
Adjustable limits: Playback output of 315 Hz to playback output
of 10 kHz: ±0.5 dB
Adjustment Location: AUDIO and main boards
Record Level Adjustment DECK B
Procedure:
1. Mode: Record
2. Mode: Playback
Confirm playback the signal recorded in step 1 become adjustable
limits as follows.
If these levels do not adjustable limits, adjustment the RV511 (L-
CH) and RV521 (R-CH) on the main board to repeat steps 1 and 2.
Adjustable limits:
CN207 PB level: 47.3 to 53.1 mV (–24.3 to –23.3 dB)
Adjustment Location: main board
[MAIN BOARD] (Component Side)
[AUDIO BOARD] (Conductor Side)
attenuator
set
CD IN connector (L: L-CH)
(R: R-CH)
1) 315 Hz
2) 10 kHz 50 mV (–23.8 dB)



600 Ω
blank tape
CS-123
AF OSC
rear panel
+
–
set
recorded
portion level mete
r
rear panel
VIDEO1
AUDIO OUT connector
(L: L-CH)
(
R: R-CH
)
set
CD IN connector (L: L-CH)
(R: R-CH)
315 Hz, 50 mV (–23.8 dB) blank tape
CS-123
600
Ω
attenuator
AF OSC
rear panel
+
–
set
recorded
portion level mete
r
rear panel
VIDEO1
AUDIO OUT connector
(L: L-CH)
(
R: R-CH
)
IC303
IC501
J301
J302
RV511
RV521
CN317
CN321
CN361 CN363
RV301
RV401 L
R
PB LEVEL
— DECK B —
— DECK A —
(NORMAL)
RV651 (HIGH) RV652
PB
LEVEL
RV311
RV411
R
L
TAPE SPEED
RL
RECORD
BAIS
RV441 RV341

— 7 —

— 8 —
SECTION 4
DIAGRAMS
4-1. CIRCUIT BOARDS LOCATION
DISPLAY BOARD
TEN KEY BOARD
SUB HP BOARD
HP BAORD
SECONDARY BOARD
DECK A BOARD
LEAF SWITCH BOARD
AUDIO BOARD
DECK B BOARD WOOFER BOARD
POWER BOARD
MAIN BOARD
TUNER UNIT
PRIMARY BOARD
AC BOARD

HST-471
4-2. BLOCK DIAGRAM
— 9 — — 10 — — 11 —
• Signal path
: TUNER/AUDIO
: PB (DECK A)
: PB (DECK B)
: REC (DECK B)
: CD
: VIDEO-1 AUDIO
: VIDEO-2 AUDIO

HST-471
4-11.IC BLOCK DIAGRAMS 4-12.IC PIN FUNCTION
• IC701 SYSTEM CONTROL (µPD780204GF-024-3A)
— 36 — — 37 — — 38 —
IC302 LC7822
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
CONTROL
LATCH
SHIFT RESISTOR
LEVEL SHIFT
CL
DI
CE
VEE
OUT
IN
OUT
IN
OUT
IN
VSS
S
RESET
VDD
OUT
IN
IN
OUT
IN
OUT
IN
1
2
3
4
5
6
7
8
9
15
10
11
12
–+
13
14
16
21
18
19
25
17
24
22
23
20
34
32
33
29
30
35
28
31
27
26
36
40
39
38
37
41
42
NOISE
FILTER NOISE
CH
BALANCE
CONTROL
VR
CONTROL
LPF
V REF
VR
VR
NOISE
GENERATOR
VCAVCA
VCAVCA
VCAVCA
VCAVCA
LPF
LPF
RECT RECT RECT RECT
P. S.P. S.
CMODE
MUTE
DIVIDER OSC
CONTROL
CTRIM
LOG
DIFF LOG DIFF
DUAL T
CONTROL
L-IN
R-IN
VSS
CLK
DATA
VCC
L-OUT
R-OUT
S-OUT
C-OUT
ENABLE
OSC1
CMODE-CAP.
C-TRIM DC CUT
R-BPF1
R-BPF2
R-BPF3
DC CUT
DC CUT
L-R RECT
L+R RECT
VCS-TH
VCS-1
VCS-2
BPF1
BPF2
VREF
S-CH DC OUT
C-CH DC OUT
L-CH DC OUT
R-CH DC OUT
VREF
L-BPF1
L-BPF2
L-BPF3
DC CUT
DC CUT
R RECT
L RECT
VLR-TH
VLR-1
VLR-2
IC303 LA2786
IC304 LV1016
15 6
+
–
+
20 19 18 17 16 15 14 13
21
22
2324
2 3 4789 10 12
11
+
DEC
IN-FILTER
(40kHz)
VDD
ADM-CONT SRAM
ADM
OUT-FILTER
(7k/5k)
B-NR
DC-OUT
VOL/MUTE
S-TRIM
INV-PHASE
R+DELAY
L+DELAY
A
B
A
B
A
B
A
B
A
B
A
B
A
B
L–R
L+R
(–6dB)
A
B
A.GND L-OUT
R-OUT
VREF S-OUT
DELAY-OUT
S-IN
R-IN
L-IN
VCC
NR-DET
ENABLE
DATA
CLK
D.GND
DC-CUT VDD OSC OSC
NR-IREF
DC-CUT
IC310 LC7824
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
CONTROL
LATCH
SHIFT RESISTOR
LEVEL SHIFT
CL
DI
CE
VEE
OUT
IN
OUT
IN
OUT
IN
VSS
S
RESET
VDD
OUT
IN
IN
OUT
IN
OUT
IN
IC332 LB1641
IC305, IC306 TDA7315
11121314151617181920
10
987654
321
SUPPLY
VOL/LOUD BASS TREBLE SPEAKER
ATT
VOL/LOUD BASS TREBLE SPEAKER
ATT
SERIAL BUS DECODER/LATCH
SCL SDA DIG GND OUT LEFT OUT RIGHT B OUT (R) B IN (R) B OUT (L) B IN (L)
LOUD
(L)
LOUD
(R)
RTREBLE
(R)
TREBLE
(L)
A GNDVSIN (R) N.CN.C
L
12 3 45 6 7 8 9 10
GND
MOTOR
DRIVE
NOISE
FILTER
CLAMP
FWD.IN
REV.IN
VCC 1 VCC 2
NOISE
FILTER
MOTOR
DRIVE
MOTOR
DRIVE
MOTOR
DRIVE
T.S.D O.C.P
FWD/REV/STOP
CONTROL LOGIC
Pin No.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
I/O
—
O
I
I
O
I
O
O
O
I
O
I
—
—
I
—
I
O
O
O
O
O
O
O
—
I
I
I
I
I
I
I
I
—
—
O
O
I
I
—
O
I/O
I/O
O
O
—
O
O
O
O
Description
5V
TUNER MUTE, H: ON.
TUNER STEREO
TUNER TUNED, L: TUNING.
TUNER PLL latch (LC72130).
TUNER PLL data in (LC72130).
TUNER PLL data out (LC72130).
TUNER PLL clock (LC72130).
TC line mute, H: ON.
Reset signal input
X’ tal (5MHz)
X’ tal (5MHz)
Ground
OPEN.
Encoder input B.
5V
Encoder input A.
FUNCTION/PRO-LOGIC/DELAY/SW clock.
FUNCTION/PRO-LOGIC/DELAY/SW data out.
FUNCTION (LC72130) latch.
PROG (LA2786)/DELAY (LV1016) latch.
S. WOOFER (LC7824) latch.
Trigger motor control.
Trigger motor control.
Ground
B DECK half input.
A DECK reel pulse input.
B DECK reel pulse input.
Key input.
Key input.
Key input.
Key input.
Destination model identification input, H: E model.
5V.
5V.
IC MUTE, L: ON.
TC REC/PB/PASS output. (HA12203NT).
POWER ON/OFF, H:ON.
SIRCS input.
Ground
Volume IC (TDA7315) clock.
Volume IC (TDA7315) data. (REAR/CENTER).
Volume IC (TDA7315) data. (BASS/TRE).
FRONT RELAY, H: ON.
SURROUND/BRIDGE RELAY, H: ON.
5V.
HEAD PHONE RELAY, H: ON.
S. WOOFER MUTE LED ON/OFF, H: ON.
PRO-LOGIC LED, H: ON.
LINE MUTE, L: ON.
Pin Name
Vdd
ST MUTE
ST STEREO
ST TUNED
ST CF
ST DI
ST DO
ST CLK
TC LINE MUTE
RESET
X2
X1
1C
XT2
VOLUME B
Vdd
VOLUME A
TA CLK
TA DATA
FUNC CE
PROG/DELAY CE
SW CE
TC B TRG
TC A TRG
AVss
B HALF
A SHUT
B SHUT
KEY 4
KEY 3
KEY 2
KEY 1
MODE
AVd d
AVd d
IC MUTE
TC REC/PB/PASS
POWER SENSE
SIRCS
Vss
SCL
SDA 2
SDA 1
FRONT - RY
SUR - RY/BRIDGE - RY
Vdd
H.P - RY
S.W MUTE LED
PROG LED
LINE MUTE

— 39 —
Pin No.
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
I/O
O
I
I
I
I
O
O
O
O
O
O
O
O
I
—
O
I
O
—
O
O
O
O
O
O
O
O
O
—
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
Description
POWER RELAY, H: ON.
HEAD PHONE input, H: ON.
TC B deck play switch, H: PLAY.
TC A deck play switch, H: PLAY.
TCA deck, half input.
TC relay, H: ON.
TC capstan motor H/L, H: LOW.
TC capstan motor ON/OFF, L: ON.
TC TRG H/L, L: LOW.
TC PB A/B, H: B DECK (HA12203NT).
TC NORM/HIGH, H: HIGH (HA12203NT).
TC BIAS, H: ON (HA12203NT).
TC REC MUTE, L: ON (HA12203NT).
PROTECTION - IN.
Not used. (Ground).
S. WOOFER RELAY, H: ON.
POWER switch (push switch).
PHASE OUT, L: inverted.
Not used. (Ground).
Fluorescent display tube.
–26V
Fluorescent display tube.
Pin Name
POWER - RY
H. P SENSE
TC B PLAY
TCA PLAY
TAA HALF
TC RELAY
TC CAP M. H/L
TC CAP M. ON/OFF
TC TRG H/L
TC A/B
TC NORM/HIGH
TC BIAS
TC REC MUTE
PROTECTION - IN
N.C
S.W -RY
POWER IN
PHASE OUT
N.C
SEGMENT 18
SEGMENT 17
SEGMENT 16
SEGMENT 15
SEGMENT 14
SEGMENT 13
SEGMENT 12
SEGMENT 11
SEGMENT 10
V load
SEGMENT 9
SEGMENT 8
SEGMENT 7
SEGMENT 6
SEGMENT 5
SEGMENT 4
SEGMENT 3
SEGMENT 2
SEGMENT 1
GRID 12
GRID 11
GRID 10
GRID 9
GRID 8
GRID 7
GRID 6
GRID 5
GRID 4
GRID 3
GRID 2
GRID 1

SECTION 5
REPAIR PARTS LIST
Note:
• -XX, -X mean standardized parts, so they may
have some differences from the original one.
• Items marked “*” are not stocked since they
are seldom required for routine service. Some
delayshould be anticipated when orderingthese
items.
• Themechanical parts with no reference number
in the exploded views are not supplied.
• Hardware (# mark) list and accessories and
packing materials are given in the last of this
parts list.
• Abbreviation
AUS : Australian
SP : Singapore
The components identified by mark !or
dotted line with mark !are critical for safety.
Replace only with part number specified.
— 40 —
5-1. MAIN SECTION
Ref. No. Part No. Description Remarks Ref. No. Part No. Description Remarks
*1 4-990-048-01 PLATE, BOTTOM
*2 1-665-245-11 SECONDARY BOARD
*3 1-665-244-11 PRIMARY BOARD
4 4-929-973-01 SCREW (CASE, 3 POINT)
*5 4-990-063-11 CASE
*6 A-4398-323-A POWER BOARD, COMPLETE (AEP,UK,AUS)
*6 A-4398-351-A POWER BOARD, COMPLETE (E,SP)
*7 1-665-242-11 WOOFER BOARD
8 3-905-609-01 SCREW (TRANSISTOR)
*10 1-665-243-11 AC BOARD
!11 1-575-653-11 CORD, POWER (E)
!11 1-690-608-11 CORD, POWER (AUS)
!11 1-751-520-11 CORD, POWER (UK)
!11 1-769-744-11 CORD, POWER (AEP,SP)
12 1-569-007-11 ADAPTOR, CONVERSION 2P (E)
*14 3-703-244-00 BUSHING (2104), CORD (AEP,UK,SP,AUS)
14 3-703-571-11 BUSHING (S) (4516), CORD (E)
*15 4-990-064-01 PLATE, BACK (AEP)
*15 4-990-064-11 PLATE, BACK (UK)
*15 4-990-064-21 PLATE, BACK (E)
*15 4-990-064-31 PLATE, BACK (AUS)
*15 4-990-064-41 PLATE, BACK (SP)
16 1-233-545-11 ENCAPSULATED COMPONENT (E,SP,AUS)
16 1-693-381-11 TUNER UNIT (AEP,UK)
*17 A-4398-354-A MAIN BOARD, COMPLETE (E,SP,AUS)
*17 A-4398-357-A MAIN BOARD, COMPLETE (AEP,UK)
18 3-704-515-01 SCREW (BV/RING)
19 4-929-973-01 SCREW (CASE, 3 POINT)
!J901 1-526-794-11 OUTLET, AC (AEP,UK,SP,AUS)
!J901 1-526-882-00 OUTLET, AC (E)
!T902 1-431-224-11 TRANSFORMER, POWER (AEP,UK,AUS)
!T902 1-431-225-11 TRANSFORMER, POWER (E,SP)