Onkyo A-8850 Service Manual

A-8850_ |
ONKYO.
SERVICE
MANUAL
Integrated Stereo Amplifier
MODEL A-8850
Black and silver models
SAFETY-RELATED COMPONENT WARNING!!
COMPONENTS IDENTIFIED BY MARK A ON THE
SCHEMATIC DIAGRAM AND IN THEPARTS LIST ARE CRITI-
CAL FOR RISK OF FIRE AND ELECTRIC SHOCK. REPLACE
THESE COMPONENTS WITH ONKYO PARTS WHOSE PARTS
NUMBERS APPEAR AS SHOWN IN THIS MANUAL.
MAKE LEAKAGE-CURRENT OR RESISTANCE MEASURE-
MENTS TO DETERMINE THAT EXPOSED PARTS ARE AC-
CEPTABLY INSULATED FROM THE SUPPLY CIRCUIT
BEFORE RETURNING THE APPLIANCE TO THE CUS-
TOMER.
Ref. No. 3405
TABLE OF CONTENTS
Specifications sci. cet andthe sa aaa aes Sele 2
PIECAULIONS fii es Rese ees Loe dae WR eat cs Bees 2
Adjustment procedures ....... 0.20 cece cece teen tees 3
IC block diagram.’ jai. pes sce vie aS a eas ee ee eS 4
Block: diaerain: .000i:2 cycacg ete aia. Bese wade eee es GS 7
Chassis exploded view ...... 0... c cece eee eee tenes 9
Printed circuit board parts list... 2.6... cece eee ee 12
Printed circuit board view ......... 00. c cece eee eee 16
Schematic diagram ...... 0.0... ccc tee tees 21
Packing: part MSt. 26 vis eee tees Face iin ayd a aes Cas 24
Front panel facilities 2.0.0... ee eee 25
System CONNECTIONS 2.0... een tne tee 25
ONKYO
AUDIO COMPONENTS

Onkyo A-8850 Specifications

General

Input Sensitivity (MM)	2.5 mV
Total Harmonic Distortion	0.008%
Input Sensitivity	150 mV (line in)
Dimensions	435 x 171 x 398mm (W x H x D)
Damping Factor	50
Signal to Noise Ratio (MM)	80 dB
Speaker Load Impedance	4 ohms minimum
Speaker Impedance	4Ω-16Ω
Tone Control	Bass, Treble

Summary

Safety-Related Component Warning

Specifications

Precautions

Replacing the Fuses

Instructions for replacing the fuses to maintain protection against fire hazards.

Adjustment Procedures

Idling Current Adjustment

Procedure for adjusting the idling current for optimal performance.

Protection Circuitry Operation Check

Verifying the proper function of the protection relay and DC detection circuitry.

IC Block Diagram

Microprocessor Pin Functions

Details on the pins of the TMP47C440AN microprocessor and their functions.

Integrated Circuit Diagrams

Block Diagram

Chassis Exploded View

Chassis Exploded View Parts List

Printed Circuit Board Parts List (Main)

Schematic Diagram

Front Panel Facilities

Front Panel Controls and Indicators

Front Panel Switches and Selectors

System Connections