Hitachi HA 3800 Service Manual

Page 1

TY No. 262 E6 F

HITACHI

SERVICE MANUAL HA-3800

CONTENTS

SPECIFICATIONS .
FEATURES.
ADJUSTMENT. ,.
DESCRIPTION OF THE NEW CIRCUITS .......
CHECKING OF THE OPERATION OF

THE PROTECTION CIRCUIT.
CIRCUIT DIAGRAM ..
PRINTED WIRING BOARD.
. DISASSEMBLY AND REPLACEMENT
. REPLACEMENT PARTS LIST .......... ,
FRONT AND REAR PANEL ....................... 17 J

SAFETY PRECAUTION \

The following precautions should be Observed when servicing.

1. Since many parts in the unit have special safety related characteristics, always use genuine Hitachis replacement parts. Especially
critical parts in the power circuit block should not be replaced with other makers.
Critical parts are marked with A in the schematic diagram and Circuit board diagram.

2. Before returning a repaired unit to the customer, the service technician must thoroughly test the unit to ascertain that it is completely
safe to operate without danger of electrical shock

/
SPECIFICATIONS

Power output
(Both channels driven)

Phono overload level 200 mV (at l kHzl
Signal-tomoise ratio lIHF A network)

35 watts per channel, min RMS at 8
ohms Irom 20 Hz to 20 kHz, with no more

than 0.05% totai hormonic distortion PHONO 80 dB
35W/Ch + SSW/ch (8 ohms, 1 kHz, TUNER, AUX, TAPE 100 dB
TH'Do'oml D ' t 30(1kH 8 h l
SSW/ch + 35W/ch (4 ohms, 1 kHz, 9'"9 am" 2: ° "'5
T.H,D. 0.05%7 Bass control :3 (18 not) Hzl

Power bandwidth 10 Hz - 30 kHz (8 ohms, l/Z Rated TVEble rNmtml :3 dB (10 kHzl
TAH-D- 01%) Loudness Control +6 118 (100 Hz)

Frequency characteristics +4 dB (10 kHz)

TUNEH, TAPE 20 Hz 7 70 kHz (+0.5, 45.0 dB) Subsonlc filtar 20 Hz

ONO AA :05 Power supply AC 120 v 60 Hz, ~220 v 50/60 Hz, -240

Harmonic distortion (8 ohms)
lat rated output)
lat 1/2 rated output)
Intermodulation distortion
(at 1/2 rated output)
Input sensitivity/Impedance
PHONO
TUNER, AUX
TAPE PLAV
Output level
TAPE REC OUT

Less than 0.05%
Les than 0.05%

Less than 0.05%

2.5 mV/47 k-Ohms
150 mV/40 krohms
150 mV/AO krohms

150 mV

Power consumption

Dimensions
Weight

V 50/60 Hz or ~120 V/ZZO V/
240 V 50/60 Hz

110 W (at 1/10 rated output)
180 W (at 1/3 rated Output)
300 W l at rated output)
435in x 83(Hl x 299(0) mm
5.8 kg

' Measured pursuant to the Federal Trade Commissions Trade Regulation Rule On Power Output

Claims for amplifiers.

FEATU RES

1. Super linear circuit tor low switching distor-

tion.

2. Equalizer circuit with high sensitivity and

S/N ratio.

3. 14 LEDs power indication.

4. Electronic protection circuit.
5. Connection facilities for two pairs of

speakers.

6. Sleek and chic design.

SPECIFICATIONS AND PARTS ARE SUBJECT TO CHANGE FOR IMPROVEMENT.

STEREO AMPLIFIER

Apfil1981

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