Onkyo T 4700 Service Manual

Page 1

T-4700

SERIAL No. 3349

ONKYO SERVICE MANUAL

SYNTHESIZED
FM STEREO/AM TUNER
MODEL T-4700

Black model
BUD, BUDN 120V AC, 60Hz
BUG 220V AC, 50Hz
BUW DOV/220V AC, 50/60Hz

SAFETY-RELATED COMPONENT WARNING"
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 COMPO'
NENTS WITH ONKYO PARTS WHOSE PART
NUMBERS APPEAR AS SHOWN IN THIS
MANUAL.

MAKE LEAKAGECURRENT 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

Specificxuiom . V .
Service procedu <
Block diagram .
Exploded View I

Pans list , I
Micmpmcu >x dc npuon
Black diagrams of [C
Adyuslmem procedures
Printed circuit board vicw
Main circuit ..............
Display/Switches/Remoccn/Volum:
Schemanc diagrm
120V model
Other models .
Printed Circuit board parts list
Packing View

I ONKYO
Alllllll flflMPflNENIS

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Page 2

SPECIFICATIONS

FM:

Tuning Range: 87.50 - l08.00 MHz (SO/ZSkHZ
steps) and/or 88,00 , 108.00MHZ

Usable Sensitivity: Mono: 10.3dBt. 0i9uV. IHF

0,8)LV DIN (75 ohms)

Stereo: 17.2dBi. 2.0,u.V. [HF

ZfluV DIN (75 ohms)
SOdB Ouieting Sensitivity: Mono: 16. I dBf, 1.7;.tV (75 ohms)
Stereo: 3o.1dBf.17)tV(7s ohms)

Capture Ratio: 1.3dB (Wide)
Image Rejection Ratio: IOOdB
IF Rejection Ratio: 100dB

Signal-to-Noise Ratio: Mono: 85dB,IHF
Stereo: 77dB. IHF

Selectivity: 60dB DIN (Narrow)
Alternate Channel
Attenuation: 80dB IHF (:400kl-Iz)

AM Suppression Ratio: SSdB

Total Harmonic Distortion: Mono: 0.03% (Wide)
Stereo: 0.07% (Wide)

Frequency Response: 30 A 15.000Hz (+0.5 - 1.0dB)

Stereo Separation: 45dB at lkHz (Wide)

33dB at 70 - 10.000Hz (Wide)
Output Voltage: 0 ~ 1V
Muting Level: 17.2dBf. 2.0MV(7Sohms)

SERVICE PROCEDURES

1. Safety-check out
(Only USA. model)
After correcting the original service problem. perform the
following safety check before releasing the set to the
customer.
Connect the insulating-resistance tester between the plug
of power supply cord and chassis.

Specifications: 3.3Mohm i10% at 500V.

2. Memory preservation

This unit does not require memory preservation batteries.
A built-in memory power backup 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
change 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. Voltage Selector (Back Panel)
W models are equipped with a voltage selector to conform
with local power supplies. Be sure to set this switch to
match the voltage of the power supply in your area before

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AM:
Tuning Range: European models:
522 7 1611kl-Iz (9kHz steps)
Canadian and USA models:
530 - 1710kHZ (10kHz steps)
Saudi Arabia &
Worldwide models:
531 - IGOZkHz (9kH7. steps)
Usable Sensitivity: 25p.V
Image Rejection Ratio: 40dB
IF Rejection Ratio: 40dB

Signal-to-Noise Ratio: 40dB
Total Harmonic Distortion: 0.7%
Output Voltage: 0~300mV
General
Dimensions (WXHXD): 435x92x366mm
171/8><3-5/8">< 14-7/16
Weight: 4.2kg 9,31bs,
Supplied accessories: 0 AM loop antcnnaXl
0 FM T-shaped antennaxl
0 Connecting cablexl
0 RI remote control cablexl
0 75/3000hm antenna adapteer
(Except 220V model)
I Remote control transmitter
Specifications and features are subeict to change without
notice.

turning the power switch on. This switch is set to 220V at
the factory. Voltage is changed by sliding the groove in the
switch with a screwdriver to the right or left, Confirm that
the switch has been moved all the way to the right or left
before turning the power switch on, Models without a
voltage selector can only be used in areas where the power
supply is the same as that of the unit

4. Tunign Step Frequency Switch (Bottom Panel)

W models are equipped with a switch for the AM
(9kHz/10kl-lz) band. The switch should be set to the proper
steps for the raido broadcast frequencies in your area.

5. Changing the AM band step

With the exception of the worldwide model, AM BAND
STEP selector switch is not provided.
when change the band step, refer the table as shown below.

MODEL BAND STEP J777
UD lOkHz-> 9kHz Additional
UG/UQ 9kHz~>10kHz Eliminated
J777
érm
0702

DISPLAY PC BOARD