Technics RSEH 750 Service Manual

Page 1

ORDER NO. 150990306408

ervice Manual

Stereo Cassette Deck

DEI- *1

Remote Control
Transmitter

*2 SB-EHTSD

*2 SB-PS75

Cassette Deck

RS-EH750

requires service, send or bring in the entire system.

AR-2 MECHANISM SERIES

Specifications

Deck system:

Track system:

Recording system:
Bias frequency;

Colour
*2 854,375 (3) ........ Silver Type
Area
(E) ........ Europe.
SL-EH'ISO sn-emso gym, 3031750
Sound Processor SH-EH750
Tuner/Amplifier SA»EH7SO
7 f" V . i CD Changer SL-EHTSO
RS-EH75O SA-EH750 *ESBvEH75O Cassette Deck RS-EH750
Front Speakers SB-EH750
Center Speakerl2 SB-PC75
wk .
Because at unique interconnecting cables, when a component surmund Speakers 2 SB P375
Stereo cassette deck SIN (Signal level = max recording level, TYPE I! type tape:
4 track, 2 channel NR off; 56 dB (A weighted)
AC bias Dolby B NR on; 66 dB (A weighted)
100 kHz Input sensitivity and impedance:
AC erase REC (IN); 400 mV/23 kit

Erasing system:
Heads:
Deck 1
(Playback head);
Deck 2
(Recording/Playback head);
(Erasing head);
Motors:
Deck 1, 2
Capstan drive:
Tape speed:
Wow and flutter:
Fast forward and rewind times:

Frequency response (Dolby NR off):

TYPE I (NORMAL);
1'va 11 (HIGH);
TYPE 1v (METAL);

Permalloy head

Permalloy head
Double gap ferrite head

DC servo motor

4.8 cm/sec.

o to 0/0 (WRMS)

Approx. 110 seconds with
0-60 cassette tape

20 H2716 kHz (DIN)
2o Hz-1s kHz (DlN)
20 Hz-16 kHz (DlN)

Output voltage and impedance:
PLAY (OUT);

Dimensions (Wx H xD):

Weight:

280 mV/SGO (t
294x118.5><281 mm
21 kg

Notes: Specitications are subject to change without notice.
Weight and dimensions are approximate.
*1: Dolby noise reduction manufactured under license lrom Dolby
Laboratories Licensing Corporation.
"Dolby" and the double-D symbol DD are trade marks of Dolby
Laboratories Licensing Corporation.

*2: Made in Singapore.

AWARNING

This service information is designed for experienced repair technicians only and is not designed for use by the general public. It does not
contain warnings or cautions to advise non-technical individuals of potential dangers in attempting to service a product.

Products powered by electricity should be serviced or repaired only by experienced professional technicians. Any attempt to service or
repair the product or products dealt with in this service information by anyone else could result in serious injury or death.

Technicsi

All rights reserved.

© 1999 Melsushita Electric Industrial Co.,Ltd.

Unauthorized copying

and distribution is a violation of law,

Page 2

I Contents Page

Location oi Controls ............................................................................. 2
Operation Checks and

Component Replacement Procedures
Service Mode Function of Cassette Mechanism
Schematic Diagram ..............
Printed Circuit Board Diagram .
Wiring Connection Diagram .

NOTE:

Refer to the service manual for Model No. SA-EH750 (ORDER No. ADSQOSOGSCZ) for information on

"Connections", "Installation", "Operations" and "Packaging.

l Location of Controls

Type Illustration of lCs, Transistors and Diodes
Terminal Function of IC's

Block Diagram ..........................
Measurements and Adjustments
Replacement Parts List ............
Cabinet Parts Location
Mechanism Parts Location

® Deck1 cassette holder open button (A OPEN)
@ Deck 1 cassette holder
@ Fast forward/rewind buttons (« , »)
(33) Deck 2 cassette holder
((31 Deck 2 cassette holder open button (A OPEN)
@ Counter reset, display buttons
(COUNTER, RESET, DISPLAY)
® Deck 1/cleck 2 select button (DECK 1/2)
@ Playback buttons and indicators (<1, l>)
The color at the indicators depends on the operation taking place.
If stopped, iast iorwarding or rewinding: orange
If playing or recording: green
While carrying out TPS or recording is on standby: flashes green
® Stop button (I)
® Dolby noise reduction button (DOLBY NR)
® Heverse mode select button (REV MODE)
@ Tape edit button (TAPE EDIT)
® Record pause button (I REC PAUSE)

"Accessories",

Page 20

RS-EH750

I Terminal Function of lC's

0 10701 (M38503M2400F) : Micro Computer

Pin Terminal Pln Terminal _
No. Name I/o Function N 0' Name l/O Function

1 Vcc | Power supply terminal 21 V58 - GND terminal

2 VREF I Reference voltage input 22 0021 | DECK1 tape detect switch signal input (ClOz)
3 AVss - GND terminal 23 MODE 1 DECK1 mechanism switch signal input (MODE)
4 LMT O Muting control signal output (Not used, open) 24 HALFt | DECK 1 mechanism switch signal input (Hall)
5 PL1 O DECK 1 solenoid control signal output 25 TPS | TPS signal input

6 M1 0 DECK 1 motor drive signal output 26 A DATA 0 Serial data signal output lor lCtO1

7 HALT I Power failure detect signal input 27 A CLK 0 Serial clock signal output for IC 101

8 EEO | Serial communication request signal input 28 A LATCH 0 Serial latch signal output for IC 101

9 OS t Serial communication complete signal input 29 PL2 O DECK 2 solenoid control signal output

10 CLK 0 Serial communication clock signal output 30 M2 0 DECK 2 motor drive signal output

_ _ . _ DOLBV NH record/playback mode select
11 DATA OUT 0 Serial communication data Signal output 31 ENC/DEC 0 signal output
DOLBY
12 DATA W 0 Serial communication data signal input 32 ON/OFF O DOLBY NR ON/OFF control signal output
_ . EEPROM chip select signal output

13 METAL 2 | DECK 2 tape detect swttch Signal (METAL) Input 33 E CS - (Not used. open)

14 CrOe 2 l DECK 2 tape detect switch signal (Cr02) input 34~36 NC - Not used, open

15 V35 7 GND terminal 37 LED ONT 0 LED color control signal output

16 FWD LED 0 LED drive control slgnal (FWD) output 38 PHOTOZ T l DECK 2 reel pulse detect signal input

_ _ DECK 2 mechanism switch signal input

17 REV LED 0 LED drive control Signal (REV) output 39 AD SW | (Half, Mode, F REC lNH., R REC INH.)

18 RESET | Reset signal input 40 PHOTO1 T | DECK 1 real pulse detect signal input

19 XIN | Clock signal input (8 MHz) 41 KEY2 l Operation key signal input 2

20 XOUT O Clock signal output (8 MHz) 42 KEY1 l Operation key signal input 1

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