Nikko alpha 440 pwr sm2

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ALPHA 440

STEREO POWER AMPLIFIER

TYPE AND VOLTAGE

W-TYPE: UL and CSA type j 120v AC

>-

E-TYPE: NK-STD type I 220v AC

TTovc SERVICE MANUAL

CONTENTS
SPECIFICATIONS ................................................................... 1
BLOCK DIAGRAM .................................................................. 2
DISASSEMBLY ..................................................................... 3
CIRCUIT DESCRIPTION .......................................................... 4~ 6
ALIGNMENT .................................................................... 7 ~ 9
SCHEMATIC DIAGRAM ......................................................... 10,11
PC. BOARD .................................................................. 12~ 15
PARTS LOCATION ................................................................ 16
POWER TRANSISTORS MOUNTING ASSEMBLY ........................................ 17
PARTS LIST ................................................................. 18~ 20
SEMICONDUCTOR DATA,
TRANSISTORS ............................................................... 21
FIELD EFFECT TRANSISTORS ................................................... 21
DIODES, LEDS .............................................................. 21
ZENER DIODES .............................................................. 21

INTEGRATED CIRCUITS .................................................... 22, 23

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SPECIFICATIONS

AMPLIFIER SECTION

Continuous Power Output per Channel:

20 ~ 20000 Hz (8 ohms) ..... more than 220 Watts
20 ~ 20000 Hz (4 ohms) ..... more than 240 Watts
1000 Hz (8 ohms) .......... more than 240 Watts
1000 Hz (4 ohms) .......... more than 240 Watts

T. H. Distortion, 8 ohms:
at Continuous Power Output . . no more than 0.008%

at 1 Watt Power Output ....... no more than 0.02%

T. H. Distortion, 4 ohms:

at Continuous Power Output . . . no more than 0.02%

I. M. Distortion, 8 ohms:

at Continuous Power Output . . . no more than 0.01%

at 1 Watt Power Output ....... no more than 0.02%
IHF Power Bandwidth, 8 ohms: ....... 10 ~ 70000Hz
Damping Factor at 1000 Hz, 8 ohms: . . . . more than 80
GENERAL

Power Requirement:

W~TYPE ................... AC 120V, 60Hz
E-TYPE ................... AC 220V, 50Hz
B-TYPE. ................... AC 240V, 50Hz
Power Consumption: ........... 800W (1.25 KVA)

Ambient Temperature during Operation: . . -10 ~ 30°C

*Specifications are subject to change without notice.

Frequency Response, NORMAL" input, 8 ohms:
at 1 Watt Power Output . . 20 ~ 100000Hz +0, -1dB

Input Sensitivity for 300 Watts Power Output:
MAIN IN ....................... 1V 1 2dB

Signal to Noise Ratio, IHF "A Network:
MAIN (NORMAL, DIRECT) . . . . better than 115dB

Signal to Noise Ratio, DIN Filter:
MAIN IN (NORMAL, DIRECT) . . better than 90dB

Channel Balance: ............... no more than 1dB

Residual Hum and Noise, 8 ohms: . . no more than 0.4 mV

Idling Current: ................... 50 ~ 150mA
Midpoint Voltage: ................... 0 3: 30mV
Muting Delay Time: ............... 2 ~ 7 seconds
Dimensions:
Width ................ 482 mm (19 inches)
Height ............... 182 mm (7 1/4 inches)
Depth ................ 460 mm (18 1/8 inches)
Weight, without package: ......... 21.5 kg (47.3 lbs)