Onkyo T 405 Service Manual

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ONKYO®

Ref. No. 3622
081 999

SERVICE MANUAL

STEREO TUNER
MODEL T-405X

UD model

Other model

Silver model

SUP, SUPT

230V AC, 50Hz

SUD, SUDT

120V AC, 60Hz

SAFETY-RELATED COMPONENT WARNINGII

COMPONENTS IDENTIFIED BY MARK A ON
THE SCHEMATIC DIAGRAM AND IN THE PARTS
LIST ARE CRITICAL FOR RISK OF FIRE AND
ELECTRIC SHOCK. REPLACE THESE COM-
PONENTS WITH ONKYO PARTS WHOSE PARTS
NUMBERS APPEAR AS SHOWN IN THIS MANUAL.

MAKE LEAKAGE-CURRENT OR RESISTANCE
MEASUREMENTS TO DETERMINE THAT
EXPOSED PARTS ARE ACCEPTABLY IN-
SULATED ROM THE SUPPLY CIRCUIT BEFORE
RETURNING THE APPLIANCE TO THE
CUSTOMER.

TABLE OF CONTENTS

Specifications ........
Service procedures
Block diagrams.
Exploded view..
Pans list ..
Printed circun board-pans 11st
Adjustment procedures .............
PC board view from soldering side ..
Schematic diagram ..........................
Microprocessor-connection diagram
Microprocessor-terminal descriptions.
IC block diagrams ...............................
Packing procedures

ONKYO.
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SPECIFICATIONS

FM
Tuning Range:
87.90 - 107.90 MHz, 200 kHz steps
(03 & Canadian models)
87.50 - 108.00 MHz, 50 kHz steps
(Ohter area models)
Usable Sensitivity:
Mono: l2.8 dBf 1.2 u\/, 75 Ohms IHF
Stereo: 19.2 CM 2.5 W, 75 Ohms IHF
SOdB Quieting Sensitivity:
Mono: 18.0 dBf 2.2 p\/, 75 Ohms
Stereo: 38,0 dBt 22 W, 75 Ohms
Capture Ratio : 1.5 dB
Image Rejection Ratio : 85 dB
IF Rejection Ratio : 90 dB
Signal~toNoise Ratio : Mono: 73 dB IHF
Stereo: 66 dB IHF
Selectivity : 50 dB DIN (:300 kHz. 40 kHz dev.)
AM SuppreSSIOn Ratio : 50 dB
Total Harmonic Distortion : Mono: 0.5%
Stereo: 08%
Frequency Response : 30 - 15,000 Hz (11.5 dB)
Stereo Separation : 40 dB at 1 kHz
30 dB at 70 - 10,000 Hz
Output Level : 0.5 V (U.S.& Canadian models)
0.75 V (Other area models)
Muting Level : 17.2 dBt 2.0 p\/, 75 Ohms

SERVICE PROCEDURES

1. Replacing the fuses

AM
Tuning Range :

530 , 1,710 kHz, 10 kHz steps
Usable Sensitivity : 30 W
Image Rejection Ratio : 30 dB
IF Rejection Ratio :40 dB
Signal-to-Noise Ratio : 40 dB
Total Harmonic Distortion : 08%
Output Level: 0.15 V

General
Power Supply:
AC 120 V, 60 Hz
AC 230 V, 50 Hz
Power Consumption : 9 W
Dimensions (W x H x D) :
205 x 76 x 279 mm
8-1/16 x3' x 11"
Weight: 1.7 kg, 3.7 lbs.

AM reception is available only on the Us. and Canadian
models.

Specifications and external appearance are subject to
change without notice as a result of product improvement.

E- This symbol located near the fuses indicates that the
fuse used is fast operating type. For continued protection against
fire hazard, replace with same type fuse. For fuse rating refer to
the marking adjacent to the symbol.

ED Ce symbole indique que le fusible utlise est a rapide.
Pour une protection permanente, n'untiliser que fusibles de
meme type. Ce darnier est la qu le present symbol est

appse,

CIRCUITNO. PART NO. DESCRIPTION
F901 252075 2.5A-SE-EAK

230V model only

2. To initialize the unit

This device employs a microprocessor to perform various
functions and operations. If interference generated by an external
power supply. radio wave. or other electrical source results in
accident which causes the specified operations and functions to
operate abnormally.

To perform a result, please follow the procedure below.

l.Press and hold down the MEMORY button. then press the
DISPLAY button.

2.After "clear" is displayed, the preset memory and each
mode stored in the memory. such as surround, are
initialized and will return to the factory setting.