Sony MHC-790 User manual

MHC-790
SERVICE MANUAL AEP Model
« MHC-790 is composed of the models below. Service SPECIFICATIONS
manuals are issued for each of the component models,
Power requirements
' so please refer to each of the manuals.
220 — 240V AC, 50Hz
Power consumption
COMPONENTS
MODEL
140W
. Dimensions Approx. 280 X 325 X 335 mm (w/h/d)
TUNER, DECK, REMOTE
CD, PLAYER, AMp| SPEAKER
incl. projecting parts and controls
HCD-H790 RM-S33
Mass Approx. 8.3kg
SS-H790 Design and specifications are subject to change without notice.
MINI Hi-Fi COMPONENT SYSTEM
SONY.

PARTS LIST
NOTE:
@ Abbreviation
@ Items marked “ * ”are not stocked since
they are seldom required for routine
G : German
service. Some delay should be antici- IT: Italian .
pated when ordering these items. EE : East Europian
Ref.No. Part No.
1-467-967-11
1-501-721-21
1-501-594-11
3-798-608-41
3-798-608-51
3-798-608-61
3-798-608-71
3-798-608-81
3-798-608-91
4~941-762-01
* 4-981~842-01
9-960-595-11
AED: Norway,Sweden,Finland, Denmark
Description Remark
REMOTE COMMANDER (RM-S33)
ANTENNA, LOOP
ANTENNA (FM)
MANUAL, INSTRUCTION
(FRENCH/SPANISH/PORTUGUESE/DUTCH) (AEP)
MANUAL, .INSTRUCTION (GERMAN) (G)
MANUAL, INSTRUCTION (ITALIAN) (AEP, IT)
MANUAL, INSTRUCTION (ENGLISH/GERMAN)
(AEP, EE)
MANUAL, INSTRUCTION (RUSSIAN/POLISH) (EE)
MANUAL, INSTRUCTION
(SWEDISH/DANISH/FINNISH) (AED)
COVER, BATTERY (FOR RM-S33)
INDIVIDUAL CARTON
Sony Corporation
Consumer A&V Products Company
Home A&V Products Div.
—?—
English
96B020443-1
Printed in Japan
© 1996.2
Published by Home A&V Products Div.
Quality Engineering Dept.

HCD-H790
SERVICE MANUAL AEP Model
9-960-594-11
Page
HCD-H801
Model HCD-H790 is almost same as HCD-H801.
As only the difference from HCD-H801 is described in this manual,
please refer HCD-H801 service manual for the other section.
HCD-H790
No. Part No. Description
* 5 4-980-806-01 PANEL, BACK (AEP)
* 5 4-980-806-11 PANEL, BACK (G)
* 5 4-980-806-21 PANEL, BACK (1T)
* 5 4-980-806-41 PANEL, BACK (EE)
or
1 X-4946-931-1 LID(A)ASSY, CASSETTE
2 X-4946-932-1 LID(B)ASSY, CASSETTE
4 4-971-955-21 PANEL, LOADING
5 4-971-956-21 BUTTON (EJ-A)
6 4-971-957-21 BUTTON (EJ-B)
9 X-4946-938-1 BRACKET (VOL) ASSY
oom oO OT
102 4-971-901-51 PANEL FRONT
104 4-971-905-01 BUTTON (EQ)
105 4-971-902-02 WINDOW (FLD)
106 4-971-913-21 BUTTON (POWER)
107 X-4946-937-1 BUTTON (CURSOR) ASSY
108 4-971-907-11 BUTTON (STR-B)
110 X-4946-936-1 BUTTON (STR-A) ASSY
111 X-4946-935-1 BUTTON (F/T) ASSY
115 4-972-642-21 BUTTON (TC-STOP)
116 X-4946-939-1 BUTTON (TC-PLAY) ASSY
117 4-970-880-31 BUTTON (KARAOKE)
121 X-4946-934-1 BUTTON(CD) ASSY
e@ Abbreviation NOTE :
G : German @ Items marked “ * ”are not stocked since
IT : Italian they are seldom required for routine
EE : East European service. Some delay should be antici-
pated when ordering these items.
COMPACT DISC DECK RECEIVER
SONY.
. English
Sony Corporation 96B020443-1
Consumer A&V Products Company ee © ee
Home A&V Products Div. Published by Home A&V Products Div.
Quality Engineering Dept.

HCD-H801
SERVICE MANUAL
@ HCD-H801 is the tuner, deck, CD and
amplifier section in FH-G80.
® HCD-H801 is the tuner, deck, CD and
amplifier section in MHC-801.
AEP Model
UK Model
E Model
Australian Model
Photo : AEP Model
CD
Ne
00.053
Section
Tape deck
Section
SPECIFICATIONS
CD player section
System Compact disc digital audio
system
Laser Semiconductor laser
Wavelength 780-790 nm
Frequency response
2 Hz - 20 kHz
Tuner section
FM stereo, FM/AM superheterodyne tuner
FM tuner section
Tuning range
87.5 — 108.0 MHz (50 kHz
step)
Aerial FM lead aerial
Aerial terminals
75 ohm unbalanced
Intermediate frequency
10.7 MHz
AM tuner section
Tuning range
AEP, UK, East European, German model :
MW : 531- 1,602kHz
LW : 153-279kHz
Italian model :
MW : 522- 1,611kHz (9kHz step)
LW : 153-279kHz
E, Saudi Arabia, Argentine, Hong Kong, Mexican,
Malaysia, Singapore, Australian model :
MW: 531 - 1,602 kHz
(9 kHz step)
530 — 1,710 kHz
(10kHz step)
SW: 5.95 - 17.9 kHz
(E3, Saudi Arabia, Hong Kong,
Malaysia, Singapore model)
Aerial AM loop aerial
External aerial terminals
Intermediate frequency
450 kHz
Tape player section
Recording system
: 4-track 2-channel stereo
Frequency response
(DOLBY NR OFF)
40 ~ 13,000 Hz (+3 dB),
using Sony TYPE I cassette
40 — 14,000 Hz (+3 dB),
using Sony TYPE II cassette
Wow and flutter
0.1% WRMS +0.3% (DIN)
— Continued on page 2 —
COMPACT DISC DECK RECEIVER
SONY.

Amplifier section
Peak music power output
1000 W
Continuous RMS power output
68 + 68 W (6 ohms at 1 kHz,
5% THD)
Inputs
AUX IN: Sensitivity 450 mV,
impedance 47 kilohms
Outputs
PHONES (stereo phone jack):
accept headphones of
8 ohms or more.
SPEAKER: accept impedance of 6 to
16 ohms.
SURROUND SPEAKER:
accept impedance of 16
ohms.
(Singapore, Malaysia,
Mexican model)
accept impedance of 8 to 16
ohms. (EXCEPT Singapore,
Malaysia, Mexican model)
Speaker section
Speaker system
3-way system
Speaker units Woofer: 15 cm dia., cone
ae Dimensions;
Frequency range
60 Hz - 20 kHz
Sensitivity 87 dB/W/m
Rated impedance
6 ohms
Dimensions Approx. 210 x 325 x
250 mm (w/h/d)
Mass Approx. 3.6 kg net per
speaker
Supplied accessories
AM loop aerial (1)
Remote (1)
Sony SUM-3 (NS) batteries (2)
FM lead aerial (1)
Speaker cables (2)
General
. Power
Destination Power requirements
. q consumption
Australian, Malaysia model | 220 — 240V AC, 50Hz 140W
AEP, German, Italian, East — 230V AC, 50/60Hz LOW
European model
E, Saudi Arabia, Argentine, | 110 — 120V/220V — 240V
Singapore, Hong Kong AC, 50/60Hz Adjustable 140W
model with the Voltage Selector
120V AC, 60Hz 140W
-; Approx..280 x 325 x ;
type i (335 mm (w/h/d) |
Tweeter:
5
cm
dia.,
cone
YP
ined:
Piejecing
parts
and’
ae
type Seitetee sts” controls.
Super tweeter: 2 cm dia., . Mass:.°. - Approx. 8. 3kg (EXCEPT ‘AEP, UK Model)
dome type “ss 4°. Approx. 7.8kg (AEP, UK Model)
Enclosure Bass reflex
. Design and Leis are vee to 2
4. change-without notice. ¢s4.6: eu Shiva
TABLE OF CONTENTS
Section Title Page Section Title Page
Specifications *+++++-2+cesssecccerseenvervsvesovsensnnsccsensnosaasveneseness l 7. EXPLODED VIEWS
ey rae SE st ao aaa ad odode aa aa alee hsneza SSulese Weds $3
1: SERVICING NOTES & 0m .sseevecteeceeev eens vcceseesastesereneonss 3 WD Fane Rael SE toil wae se Sela aheousstseeasadopedsccd 55
7-3. Front Panel Section-2 Pome merece eee e eee ee ee es ee eeeeseeeeeese 56
. Macnee Aue COLES LSKe ee roneria Aehe enon nae 4 TAo TC Mechanism Secon | -ettatwatetieesrentecdscacapetss 57
(TCM-220WR2)
3. DISASSEMBLY 7-5. TC Mechanism Section-2:etrrerssesetereeeeereeeceeeseeeenes 58
CME BIEMU (rc er Cr wot ite Ror reer reer eer eee 6 (TCM-220WR2)
3-9 “Front Panel Renrvoval esnxtsscavenvssgass anenararsraiersacens 6 9.6 TC Mechanisin: SEGHOIe 3818) oie end Aiton sasencadocceaerebecn 59
3-3 "TOC Mechanisin Removal os errsavmnon eaves ees tecdeenes a (TCM-220WR2)
7-7. CD Mechanism Section-1 (CDM28-5BD19) +1+++++++++ 60
4. ADJUSTMENTS :--- ede’ ya Wh acne onmeaoes sada Ba Ghua le se Seameoeesas Fi 9 7-8. CD Mechanism Section: 24 BU-SBDI9) es cuewnes 61
4-1. Mechanical Adjustments eee eee cece ene n erect reece ee eereseeeees 8
4-2. Electrical Adjustments++++++++++++ssessereseceeceseesenennees 8 8. ELECTRICAL PARTS LIST --:-:::ccccecsecececeentenee enter es 62
5. EXPLANATION OF IC TERMINALS ------+-+----+-esseeee 14
6. DIAGRAMS
6-1. Block Digeram== CD Séetion = sesieaeteictintians 19
6-2. Block Diagram — Main Section — :rrrrrrrersereeee seen 21
6- 3 Circuit Board Location Pee mere rene recor oeseeeereeessessene 26
6-4. Printed Wiring Boards — Main Section — -+++++++++++- 27
6-5. Schematic Diagram — Main Section — srrrre+eseeeeee ee 3]
6-6. Schematic Diagram — Panel Section — -+r++++ereeeeee ee 36
6-7. Printed Wiring Boards — Panel Section — -+++++++++++- 39
6-8. Printed Wiring Boards — BD Section —-+++++++++eeeeee 41
6-9. Schematic Diagram — BD Section — -rrrrseeeee eres eee 42
6-10. Printed Wiring Boards — Audio pechery Fe Meese NSN eS 46
6-L1. Schematic Diagram — Audio Section — ++++rrrereereee 48
6-12. IC Block Diagrams — Main Section — -++++e+eeeeeeeee |

MODEL IDENTIFICATION
— BACK PANEL —
4-971-977-0(]: AEP (AE1) model
4-971-977-1]: AEP (AE2) model
4-971-977-2(_]: IT model
4-971-977-3L: G model
4-971-977-4[_]: UK (UK2) model
4-971-977-5(_]: EE model
4-971-977-6L_]: AEP (AE1) model
4-971-978-0(_]: E model
4-971-978-1]: EA model
4-971-978-2[_]: AUS model
4-971-978-3(]: SP model
4-971-978-4(_] : MX model
4-971-978-5[_]: MY model
4-971-978-61]: AR model
4-971-978-7[_]: HK model
SAFETY-RELATED COMPONENT WARNING!!
COMPONENTS IDENTIFIED BY MARK A OR DOTTED
LINE WITH MARK A 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.
SECTION 1
SERVICING NOTES
NOTES ON HANDLING THE OPTICAL PICK-UP BLOCK
OR BASE UNIT
The laser diode in the optical pick-up block may suffer electrostatic
breakdown because of the potential difference generated by the
charged electrostatic load, etc. on clothing and the human body.
During repair, pay attention to electrostatic breakdown and also use
the procedure in the printed matter which is included in the repair
parts.
The flexible board is easily damaged and should be handled with
care.
NOTES ON LASER DIODE EMISSION CHECK
The laser beam on this model is concentrated so as to be focused on
the disc reflective surface by the objective lens in the optical
pick-up block. Therefore, when checking the laser diode emission,
observe more than 25cm away form the objective lens.
CHUCK PLATE JIG ON REPAIRING
On repairing CD section, playing a disc without the CD lid, use
Chuck Plate Jig.
@ Code number of Chuck Plate Jig : X-4918-255-1
Laser component in this product is capable of emitting radiation
exceeding the limit for Class 1.
This appliance is classified as a
CLASS 1 LASER product.
The CLASS 1 LASER
PRODUCT MARKING is
located on the rear exterior.
m CLASS 1 LASER PRODUCT
LUOKAN 1 LASERLAITE
m KLASS 1 LASERAPPARAT
This caution
label is located
inside the unit.
CAUTION ; INVISIBLE LASER RADIATION WHEN OPEN,
AVOIO EXPOSURE TO BEAM.
> USYNLIG LASERSTRALING VED ABNING NAR
ADVARSEL ; SIKKERHEOSAFBRYOERE ER UDE AF FUNKTION,
UNOGA UDS ZTTELSE FOR STRALING.
VARO! ; AVATTAESSA JA SUOJALUKITUS OHITETTAESSA
OLET ALTTIINA LASERSATEILYLLE.
te rere nree aoe emanating as
VARNING _ ; LASERSTRALING NAR DENNA DEL AR OPPNAD
OCH SPARREN AR URXOPPLAD,
earn nnemetiania
ADVARSEL 3; USYNUG LASERSTRALING NAR DEKSEL APNES
UNNGA EKSPONERING FOR STRALEN.
CAUTION
Use of controls or adjustments or performance
of procedures other than those specified herein
may result in hazardous radiation exposure.

SECTION 2
GENERAL
This section is extracted from
instruction manual.
SEE a ee, SE eae a ee
index to Parts and
Controls
Refer to the pages indicated in parentheses
for how to use the controls.
Controls with an asterisk have indicators
on themselves.
Front Panel
CD player
[1] SYSTEM POWER ON/STAND BY
switch (7)
[21 CD trav (7)
(3] 2 OPEN / CLOSE button (7)
[4j (stop) button (7)
00 (play and pause) button* (7)
[6] CD operating buttons
CONTINUE button (8)
SHUFFLE button (8)
PROGRAM button (8)
Tuner/Amplifier
EQ CONTROL button* (18)
{2] MEMORY button (18)
USER FILE button* (18)
Preset equalizer setting buttons* (17)
[5] DBEB button (17)
[6] SURROUND button (17,21)
CLOGK SET button (6)
VOLUME control (17,19)
[9] DISPLAY button (6,7)
FUNCTION button (8,14,21)
Timer operating buttons
TIMER SET button (19)
DAILY button (19)
TIMER REC button (20)
(12) Tuner operating buttons
TUNING MODE button (10,20)
MONDO button (10)
[13] TUNER MEMORY button (11)
Jog dial (6,7,10,14,19)
ENTER/NEXT button* (6,11,19)
TUNER/BAND button* (10,15,20)
Tape player
eed
E, EA, AR, HK, MX,
MY, SP, AUS model
[1] @ REC button* (13)
[2] HIGH SPEED DUBBING button (16)
[3] DOLBY NR button (12)
[4] DIRECTION button (12)
CD SYNCHRO button (13)
[6] §f PAUSE button* (12)
DECK A/DECK B button and A/B
lamps (12)
[8] & EJECT button (for deck A) (12)
[9] PHONES jack (17)
10) MIX MIC jacks (21)_
MIC VOLUME control (21) | E, EA, AR, HK, MX,
4] ECHO VOLUME control (21), MY, SP, AUS model
Tape compartments (12)
KARAOKE PON/MPxX button (21)
EJECT button (for deck B) (12)
PP (fast rightward) (12)
<4 (fast leftward) buttons (12)
@ (stop play) button (12)
(18] c (front side play)* (12)
<J (reverse side play) buttons* (12)

Rear panel
AEP, G, IT, EE, UK model
FM 75 Q COAXIAL terminal (4) :
AEP, G, IT, EE, UK model
FM 75 Q terminal (4) :
E, EA, AR, HK, MX, MY, SP, AUS model
+h earth terminals (4)
AM terminal (4)
AUX IN jacks (21)
SPEAKER connectors (4)
[6] SURROUND SPEAKER connectors (21)
[7] + ground terminal (4)
Mains lead (5)
[9] VOLTAGE SELECTOR (5):
E, EA, AR, HK, MX, MY, SP, AUS model
Display window
Spectrum analyzer (18)
Tape direction indications (12)
Tuner indications (10)
DOLBY NR indication (12)
Karaoke indication (21)
[6] TIMER/DAILY/REC/SLEEP indication
(19,20)
DBFB/SUR indications (17,21)
Function indication (14,16)
{9] AUTO/TUNING/PRESET/STEP
indications (10,11,20)
Frequency/time indication (6,10)
Music calendar (7)
CD play mode indications (8,9)
VOLUME indication (17)
E, EA, AR, HK, MX, MY, SP, AUS model
Remote (RM-S33)
SLEEP button (19)
FUNCTION button (8,14,21)
MD operating buttons
BP (play) button
Hi (pause) button
M@ (stop play) button
[4] CD operating buttons
B (play) button (7)
Hf (pause) button (7)
Mi (stop play) button (7)
Ke / Pi (AMS) buttons (7)
<< />P (fast forward/fast reverse)
buttons (7)
REPEAT button (9)
EDIT button (14)
CHECK button (8,14)
CLEAR button (8)
[5] Tuner operating buttons
BAND button (10,15,20)
PRESET (+/-) buttons (11)
[6] Tape operating buttons
—@ /P buttons (12)
Mi button (12)
<< /P> buttons (12)
[7] TAPE A/B buttons (12)
SYSTEM POWER button (7)
[9] VOL(+/-) buttons (17,19)
* Abbreviations
G : German MX: Mexican
IT : Italian MY: Malaysia
EE :EastEuropean SP: Singapore
AUS : Australian
EA: Saudi Arabia
AR_ : Argentine
HK _ : Hong Kong

SECTION 3
DISASSEMBLY
Note : Follow the disassembly procedure in the numerical order given.
3-1.CD MECHANISM REMOVAL
ar he ere @ Tow screws (+BVTP3x8)
02,
@ Wire (Flat type)(21Core)
CN111
@ Disc Table @ CN291 (5Pin)
© Loading panel
3-2. FRONT PANEL REMOVAL
@ Holder PCB
Front Panel Section
© CN103 (5Pin)
@
Three
crows
@
CN102
(6Pin)
@ Wire (Flat type)(17Core)
CN105
© Wire (Flat type)(21Core)
CN401
©@ Wire (Flat type)(11Core)
CN402
@ Tow screws (+BVTP3X8) | @ Two screws (+BVTP3X8)

3-3. TC MECHANISM REMOVAL
@ Five screws (+BVT2.6X 8)
TC Mechanism
@ Lid (B) assy, cassette ;
@ Eject button