Onkyo TX 850 Service Manual

Page 1

SERIAL NO. 3292

ONKYO SERVICE MANUAL

QUARTZ SYNTHESIZED
TUNER AMPLIFIER
MODELS TX-850/TX-850M

Black modal

BHUD, BHUDN, MBHUDN

120V AC, 60Hz

BHUG

220V AC. SDI-[z

BIIUQA

240V AC, 5 0H2

BHUW, MBHUWX

120/220v AC, 50/60Hz

SAFETY-RELATED COMPONENT WARNINGI!
COMPONENTS IDENTIFIED BY MARK A ()N
THE SCHEMATIC DIAGRAM AND IN THE PARTS
LIST ARE CRITICAL FOR RISK OF FIRE AND
ELECTRIC SHOCK. REPLACE THESE COMPO
NENTS WITH ONKYO PARTS WHOSE PART
NUMBERS APPEAR AS SHOWN IN THIS
MANUAL.

MAKE LEAKAGE-CURRENT 0R RESISTANCE
MEASUREMENTS TO DETERMINE THAT EXPOSED
PARTS ARE ACCEPTABLY INSULATED FROM
THE SUPPLY CIRCUIT BEFORE RETURNING

THE APPLIANCE TO THE CUSTOMER.

I ON KYO
AIIIIIII BflMPIINHIIS

TABLE OF CONTENTS

Specifications ----------------- 2
Service procedures ---------------- 3
Explndfd View ........................ 4
Parts list ----------- 5
Block diagram *IZOV model ------------- - 6
Block diagram 220V model --------------- Y
Connection diagram of microprocesmr ----------- 10
Block diagram of IC ----------------- ll
Adjustment procedures ------------------- 18
PC board view/parts list
Display / preamp/speaker ------ ----------- 21
AM/FM tuner and selector circuit ------------ 25
Power amplifier ------------------ 30
Other pc boards ---------------------- 33
Schematic diagram
120V model *Tuner ' """""""""""" Z3
120V model *Amp ----------------- 27
Other models 'TLUIEI ---------------- ' ~ ~ ' 31
Other models *Amp. """""""""""""" 35
Disassembling procedures ----------------- 37
Packing vie ......................... 38