Onkyo T 4150 Service Manual

Page 1

T4150

SERIAL NO. 3254

ONKYO SERVICE MANUAL

SYNTHESIZED
FM STEREO/AM TUNER
MODEL T-4150

uNuvn ,m

Black model
BUD, BUDN 120V AC. 60H:
BUG 220V AC, SOHZ
BUW DOV/220V AC, 50/60Hz
BUQA 240V AC, SOHZ

SAFETY-RELATED COMPONENT WARNINGH
COMPONENTS IDENTIFIED BY MARK [2: ON
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 OR RESISTANCE
MEASUREMENTS TO DETERMINE THAT EXPOSED
PARTS ARE ACCEPTABLY INSULATED FROM
THE SUPPLY CIRCUIT BEFORE RETURNING

THE APPLIANCE TO THE CUSTOMER.

TABLE OF CONTENTS

Specifications ............................... 2
Service procedures ............................ 2
Blank diagram ............................... 3
Exploded View ............................... 4
Fans 11's: .................................. 5
Circuit description ............................ 6
BIock diagram of IC ........................... 8
Adjustment procedures ......................... ll
Schematic diagram ........................... 13

220V/240V models ......................... 1 3

1 20V model ............................. 17

Worldwide model .......................... 21
Pc board View .............................. 15

Main circuit ............................. IS

Display/Operation switch ..................... 23
Pc board-parts list ............................ 19
Packing View ............................... 24

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_1_

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4150

SPECIFICATIONS

FM: 120V model
Tuning Range: 87:9-107.9MH2(200kHz steps)

Other models
87.5-108.0MH2(50kHz steps)

Usable Sensitivity: Mono: 10.3dBf, 0.9uV.lHF(750hm) 10.3 (181, 0.9uV, lHF, 0.8uV, 750hms DIN
Stereo: 17.2dBf, 2.0;:V(7$ohm) 2.0uV 7Sohm

SOdB Quieting Sensitivity: Mono: 16.1dBf, l.7uV(7Sohm) 1.7uV 7Sohm
Stereo: 36.1dBf, 17;;V(750hm) 17pv 7Sohm

Capture Ratio: 1.3dB l.3dB(Wide)

Image Rejection Ratio: 70dB 70dB

IF Rejection Ratio: 90dB 90dB

Signal-tO'Noise Ratio: Mono: 75dB Mono: 75dB
Stereo: 73dB Stereo: 73dB

ACA: BOdB lHF(i400kHz) (Narrow)

Selectivity: 60dB DIN(t300kl-lz, 40kHz devi.)

AM Suppression Ratio: 50dB 50dB

Total Harmonic Distortion: Mono: 01% (Wide) Mono: 0.1%(Wide)
Stereo: 0.2% (Wide) Stereo: 0.2% (Wide)

Frequency Response:
Stereo Separation: 45dB at lkHz (Wide)
30dB at 70-]0,000H2(Wide)

Output voltage: GOOmV

Muting level: 17.2dBf, 2.0uV (750hm)

AM:

Tuning Range: 530~l,620kH2(10kHz steps)

Usable Sensitivity: ZSyV

Image Rejection Ratio: 40dB

IF Rejection Ratio: 30dB

Signal-torNoise Ratio: 40dB

Total Harmonic Distortion: 0.8%

Output voltage: ISDmV

GENERAL:

Dimensions(WXH XD): 435x72x368mm
17-1/S"X2- 3/4 "X 14-1/2 "

Weight: 3.7kg 8.21115.

30'15,000Hz (+0.5~ '1.0dB)

30r15,000Hz(+0.5~ -1.0dB)
45dB at lkHz(Wide)

30dB at 70*10.000Hz (Wide)
BOOmV

2pV,750hm

521~1,6 1 1kHz(9kHz steps)
25;: V

40dB

30dB

40dB

0.8%

150mV

Specifications and features are subject to change without notice.

SERVICE PROCEDURES

1.Safety-check out

(Only U.S.A. model)

After correcting the original service problemperform
the following safety check before releasing the set to
the customer.

Connect the insulating-resistance tester between the
plug of power suuply cord and chassis.

Specifications: 3.3Mohm $1096 at 500V.

2.Mernroy preservation

This unit does not require memory preservation batteries.

A built-in memory power back-up system preserves contents
of the memory during power failures and even when the
unit is unplugged, The unit must be plugged in and the
power switch turned on and off once in order to charge the
back-up system. Note that since this is not a permanent
memory,the power switch must be turned on and off a few
times each month to keep the backup system operative.
The period of time during which memory contents are
preserved after power has last been turned off varies
depending on climate and placement of the unit.

On the average. memory contents are protected over a
period of 3 to 4 weeks (a minimum of 2 weeks) after

the last time power has been turned off. This period is
shorter when the unit is exposed to very high humidity or
used in an area with an extremely humid climate.

3. Change of FM/AM band step.

7 120V model -

This model is not located the band selector switch.

If the FM band step is changed from 200kHz to 50kHz, add two
diodes (188133) to D707 and D708 on the ma i n PC board,

If the AM band step is changed from 10kHz to 9kHz, add a diode
(188133) to D710 on the main PC board:

7220V model 7

This model is not located the band selector switch.

If the FM band step is changed from 50kHz to ZOOKHZ, remove two
diodes (188133) to D707 and D708 on the ma i n PC board.

If the AM band step is changed from 9kHz to lokl-lz, remove a
diode (188133) to D710 on the main PC board