Sony ta h 4800 service manual

Page 1

TA-H48IIII

SERVICE MANUAL

TAAH4800 is the Power amplifier
section in MHC-4800/FH

AEP Model

E Model
Australian Model
Tourist Model

For Europe

Continuous HMS power output
60 + 60 watts
(6 ohms at 1 kHz, DIN)
70 + 70 watts

(6 ohms at 1 kHz, 5% THD)
Music power output 140 + 140 watts

(6 ohms at 1 kHz, 10% THD)
For Australla
Contlnuous RMS power output

70 + 70 watts

(15 ohms at 1 kHz, 5% THD)
Peak music power output

800 watts (4 speaker driven)

For other countrles
Peak music power output
800 watts (4 speaker drlven)
Comlnuous HMS power output
70 + 70 watts
(16 ohms at 1 kHz, 5% THD)
Inputs MIX MIC (miniieok)
sensltlvlty: 1 mV,
impedance: 600 ohms
Outputs HEADPHONES
(stereo minijeck)
accepts headphones of
5 ohms or more
SPEAKER
accepts speakers at 6 lo
16 ohms
SURROUND SPEAKER (phono
jacks)
(Model for Europe)
accepts speakers oi
16 ohms
(Model Ior other countries)
accepts speakers at B to
16 ohms

SPECIFICATIONS

General
Power requirements

Power consumption

Dlmensions

Mass

Supplied accessories

European model:
220 V - 230 V, 50/60 Hz
Model for other countries:
110-120V, or 220-240V
AC aiustable, 50/60 Hz
European model:
180 watts
Model tor other countries:
210 watts
Approx. 225 x 390 x 280 mm
(w/h/d)
(87/; x15/ x 11 I9 in.) incl.
projecting parts and.controls
Approx. 13 kg (28 lb 11 oz)

Remote Commander (1) (RM-$380)
Sony SUM-3 (NS)
batteries (2)
AM loop antenna (1)
FM antenna (1)
AC power cord (2)
Flat cord (1)
Speaker cord (2) (except lor
Europe)

Design and specifications subject to change

without notice.

Note

This appliance conforms with EEC Directive
87l308/EEC regarding interlerence

suppression

POWER AMPLIFIER
S O NYE

Page 2

SAFETY CHECK-OUT

After correcting the original service problem,
perform the following safety check before releasing
the set to the customer:

Check the antenna terminals, metal trim, metallized
knobs, screws, and all other exposed metal parts for
AC leakage. Check leakage as described below.

LEAKAGE TEST

The AC leakage from any exposed metal part to
earth ground and from all exposed metal parts to any
exposed metal part having a return to chassis, must
not exceed 0.5 mA (500 microampers). Leakage
current can be measured by any one of three
methods.

1. A commercial leakage tester, such as the
Simpson 229 or RCA WT-540A. Follow the
manufacturers instructions to use these instm»
ments.

2. A battery-operated AC milliammeter. The Data
Precision 245 digital multimeter is suitable for
this job.

3. Measuring the voltage drop across a resistor by
means of a VOM or battery-operated AC volt-
meter. The limit indication is 0.75 V, so
analog meters must have an accurate low-
voltage scale. The Simpson 250 and Sanwa
SH-63Trd are examples of a passive VOM that
is suitable, Nearly .all battery operated digital
multimeters that have a 2 V AC range are
suitable. (See Fig. A)

To Exposed Metal
Parts on Set

AC
0. 15.: g 1.5m voltmeter
L (o. 75 v;

r Earrh Ground

Fig. A. Using an AC voltmeter to check AC leakage.

TABLE OF CONTENTS

Section T aitle Page
1 . G E N ERA L
~ Parts Identification .................................................................. 3

2. DAIAG RAMS

2-1.
22.
2-3.
2-4.
2-5.

Block Diagram ................................................................... 4
Circut Boards Location .
Printed Wiring Boards
Schematic Diagrams .
Semiconductor Lead Layout ........................................... 16

3. EXPLODED VIEWS

3-1.
3-2.

4. ELECTRICAL PARTS LIST

Case and Front Panel Assembly .................................... 19
Chassis AssemblyZO

SAFETV-RELATED COMPONENT WARNING

COMPONENTS IDENTIFIED BY MARK AOR DOTTED
LINE WITH MARKAON 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 BV SONY.