Sony TC-WE425 Service Manual

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Model Name Using Similar
Mechanism
NEW
Tape Transport DECK A TCM-230ASR1
Mechanism Type DECK B TCM-230ASR2
SERVICE MANUAL
US Model
TC-WE425/WR681
Canadian Model
TC-WE425
AEP Model
TC-WE525/WR681
UK Model
TC-WE525
E Model
Australian Model
TC-WE425/WR681
Chinese Model
TC-WE425
TC-WE425/WE525/
WR681
STEREO CASSETTE DECK
MICROFILM
System
Recording system
4-track 2-channel stereo
Fast-winding time (approx.)
100 sec. (with Sony C-60 cassette)
Bias
AC bias
Signal-to-noise ratio (at peak level and weighted with Dolby NR off)
Type I tape, Sony Type I (NORMAL): 55 dB
Type II tape, Sony Type II (HIGH): 57 dB
Type IV tape, Sony Type IV (METAL): 58 dB
S/N ratio improvement (approximate values)
With Dolby B NR on: 5 dB at 1 kHz, 10 dB at 5 kHz
With Dolby C NR on: 15 dB at 500 Hz, 20 dB at 1 kHz
Harmonic distortion
0.4% (with Type I tape, Sony Type I (NORMAL):
160 nWb/m 315 Hz, 3rd H.D.)
1.8% (with Type IV tape, Sony Type IV (METAL):
250 nWb/m 315 Hz, 3rd H.D.)
SPECIFICATIONS
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Photo: TC-WE425
Dolby noise reduction extension manufactured under license
from Dolby Laboratories Licensing Corporation.
HX Pro originated by Bang & Olufsen. “DOLBY”, the double-D
symbol a and “HX PRO” are trademarks of Dolby Laboratories
Licensing Corporation.
Frequency response (Dolby NR off)
Tape type
Type I tape, Sony Type I 30-16,000 Hz (±3 dB, IEC),
(NORMAL) 20-17,000 Hz (±6 dB)
Type II tape, Sony Type II 30-17,000 Hz (±3 dB, IEC),
(HIGH) 20-18,000 Hz (±6 dB)
Type IV tape, Sony Type IV 30-19,000 Hz (±3 dB, IEC),
(METAL) 20-20,000 Hz (±6 dB),
Wow and flutter
± 0.15% W. Peak (IEC)
0.1% W. RMS (NAB)
± 0.2% W. Peak (DIN)

Sony TC-WE425 Specifications

General

Track System	4-Track, 2-Channel Stereo
Tape Speed	4.8 cm/s
Signal to Noise Ratio (Dolby B)	78 dB
Power Supply	AC 120V, 60Hz
Dimensions	440 x 130 x 270 mm
Weight	4.5 kg
Type	Double Cassette Deck
Motor	DC servo
Wow and Flutter (WRMS)	0.08%
Output	0.5V (line)
Inputs	Line In
Outputs	Line Out

Summary

SPECIFICATIONS

System

Details about recording, bias, SNR, and distortion.

Frequency Response

Characteristics for different tape types.

Wow and Flutter

Specifications for wow and flutter measurements.

SAFETY CHECK-OUT

LEAKAGE TEST

Procedures and limits for electrical leakage testing.

MODEL IDENTIFICATION

SECTION 1 GENERAL

LOCATION OF CONTROLS

Identifies all controls on the front panel with descriptions.

SECTION 2 DISASSEMBLY

CASE AND FRONT PANEL DISASSEMBLY

Instructions for removing the outer case and front panel.

CASSETTE LID AND MECHANISM DISASSEMBLY

Instructions for removing cassette lid and mechanism deck assemblies.

LEAF SWITCH BOARD DISASSEMBLY

Instructions for disassembling leaf switch boards.

PINCH LEVER AND FLYWHEEL DISASSEMBLY

Instructions for disassembling pinch lever and flywheel assemblies.

MECHANICAL BLOCK AND HEAD RELAY DISASSEMBLY

Instructions for disassembling mechanical block and head relay boards.

SECTION 3 MECHANICAL ADJUSTMENTS

SECTION 4 ELECTRICAL ADJUSTMENTS

SECTION 5 DIAGRAMS

IC PIN DESCRIPTION

Details pin functions for the system controller IC.

CIRCUIT BOARDS LOCATION

Illustrates the physical location of all circuit boards.

MAIN SECTION DIAGRAMS

Printed wiring and schematic diagrams for the main section.

PANEL SECTION DIAGRAMS

Printed wiring and schematic diagrams for the panel section.

POWER SECTION DIAGRAMS

Printed wiring and schematic diagrams for the power section.

DECK A SECTION DIAGRAMS

Printed wiring and schematic diagrams for the Deck A section.

DECK B SECTION DIAGRAMS

Printed wiring and schematic diagrams for the Deck B section.

SECTION 6 EXPLODED VIEWS

CASE AND CHASSIS EXPLODED VIEWS

Exploded views of the case, chassis, and related parts.

CASSETTE HOLDER EXPLODED VIEW

Exploded view of the cassette holder and its components.

FRONT PANEL EXPLODED VIEW

Exploded view of the front panel and its components.

TAPE MECHANISM EXPLODED VIEW

Exploded view of the tape mechanism and its components.

SECTION 7 ELECTRICAL PARTS LIST