Sansui D 75BW Service Manual

Page 1

D-753W

SERVICE MANUAL

Track format ................... 4-track/2-channel system
Tape speed ...................... 4.8 cm/sec..
Heads

STEREO DOUBLE CASSETTE DECK Rec/play head ............. HIGH-BS hard permalloy

Play head ................ HIGH-BS hard permalloy
Erase head... ..... Double-grep HlGH-Bs ferrite

Motor ................... Electronically controlled DC
I motorx 2
Reels: DC Motoer

(Silver & Black Model) Wow/flutter .................... 0.06% max (WRMS)

Fast forwarding (rewinding) time
.................................. Approx. 85 sec.
(for 060 tape)
Frequency response (-20 VU recording/playback)
Normal tape (Ll-l) ....... 20 to 15,000 Hz
(30 to 14,000 Hz;l:3 dB)

Chrome Tape ............. 20 to 16,000 Hz
(30 to 15,000 H2i3 dB)
Metal Tape ................. 20 to 17,000 HZ

(30 to 16,000 H213 dB)
Erasure rate (metal tape)
.................................. 70 dB min (1 kHz)
Recording bias frequency

.................................. 85 kHz
Input sensitivity/impedance
LINE IN (REC) ............. 150 mV/47 1(0th

Signal to noise ratio (Record/Playback)
Metal Tape (without Dolby Noise Reduction)
............................. better than 54 dB
(With Dolby Noise Reduction Effect)

IL DOLBY "B" NR better than 64 dB
(above 5 kHz)
CAUTION Power requirements
. ' . Power voltage ............. 120/220/24OV (50/60 Hz)
1. Parts Identified by theAsymbol on the schematic For US-A- and Canada
diagram and the parts list are critical for safety. powerggggg}551{55"i'i3035;? HZ)
Use only replacement parts that have critical charac- Dimensions ..................... 430 mm (16-15/16) w
terlstics recommended by the manufacturer. 112 mm (4-7/16"J H
2. Make leakage-current or resistance measurements . 2 mm (33 ) D
. . Weight ............................ 4.1 kg (90 lbs.) net
to determine that exposed parts are acceptably in-
sulated from the Supply Circuit before returning the Design and specifications subiect to changes without notice for im-
- V ment .
appllance t0 the customer. ' pNZJOiszreduzlion system manulatlured underlicensetrom Dolby Laborato-
ri slicensin or r ion.
- j "Bolby" an: [$16 Sguzlle D symbol are trade marks of Dolby laboratories

Licensing Corporation.

SANSUI ELECTRIC CO., LTD.

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1. The symbols, UL, CSA,

CAUTION
SA, BS, UK, EU, AS, xx and

XX-V < EXPORT(V)> on the parts list and the schematic diagram
mean followings respectively.

UL ............................... Manufactured for U.S.A market.
(Undenivriters Laboratories approved model.)

CSA ............................ Manufactured for Canadian market.

SA ............................... Manufactured for South African market.

BS, UK ........................ Manufactured for United Kingdom market.

EU .............................. Manufactured for European market.

AS ............................... Manufactured for Australian market.

XX ........... Standard Version with Inner Voltage
Selector.

XX-V .... Standard Version with Outer Voltage
Selector.

NON MARK ................ Common Parts.

2. Some printed circuit boards are not supplied as the assembled.
To separate these in this service manual, the stock Nos are not in-
dicated at the ends of the board names. However, the individual parts
on the circuit boards are provided by orders.

3. Since some of capacitors and resistors are omitted from parts lists
in this service manual, refer to the Common Parts List for capacitors
& resistors, which was issued on February 1983.

4. Abbreviations in this service manual are as follows.

~ 0Abbreviations List

C.R. : Carbon Resistor E.B.L. : Low Leak Bi-Polar

S.R. V: Solid Resistor Electrolytic Capacitor

Ce.R. : Cement Resistor Ta.C. : Tantalum Capacitor

M.R. : Metal Film Resistor F.C. : Film Capacitor

F.R. : Fusing Resistor MP. : Metalized Paper Capacitor

N.|.R. : Non-inflammable Resistor P.C. : Polystyrene Capacitor

A.R. : Array Resistor G.C. : Gimmic Capacitor

C.C. : Ceramic Capacitor A.C. : Array Capacitor

C.T. : Ceramic Capacitor, V.R. : Variable Resistor
Temperature Compensation S.V.R. : Semi Variable Resistor

E.C. : Electrolytic Capacitor SW. : Switch

E.L. : Low Leak Electrolytic Chip R. : Chip Resistor
Capacitor Chip C. : Chip Capacitor

EB. : Bi-Polar Electrolytic

Capacitor

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4-3. Front View of Mechanism Chassis

/Reel Motor
F
ldler
Reel
Assisi Gear
Erase Head
U l | /
/ \
Head Slider REC/PB Head Pinch Roller Assy

4-4. Cam Positions in the Modes of PLAY, FF, REW & STOP

'STOP, FF, REW 'PLAY 'AMPS

Lock Arm Assisi Gear