Sony wm fx 421 v service manual

Page 1

WM-FX421V

srfiwcr MANUAL

E Model

Model Name Using Similar Mechanism

WM- FX303

Tape Transport Mechanism Type

MF-WMFXSOS-43

SPECIFICATIONS

Radio Frequency

FM 1875-108 MHZ (Oil MHZ)
AM 2530- 1,710 kHz (9 kHz step)

Power Requirements
. 3V DC Batteries R6 (AA) x 2
~ External DC 3 V power sources

Supplied Accessories
- Stereo headphones ( I)
- Belt clip (I)

Desrgn and specifications are subject to change without notice.

Note:

Use only the recommended AC-E30HG
AC power adaptor (not supplied). Do not

use any other AC power adaptor.

Battery Life
(approximate hours when using the batteries specified below)
Battery Playback Radio
Sony Alkaline LRG (SO) 13 hours 20 hours
Sony R6? (SR) 4 hours 12 hours
Dimensions

ll6.5 x 86.3 x 34.6 mm (4 5/8 x 3 1/2 x 1 3/8 in.)(w/h/d)
incl. projecting pans

Mass
210g (75 oz) incl. batteries

MICROFILM

W

Polarity of the plug

RADIO CASSETTE PLAYER
ONY;

Page 2

TABLE OF CONTEMTS

Section Title Page

SECTIONI GENERAL ..

SECTION 2 DISASSEMBLY

2-l. Cabinet (Rear) Assembly
2»2i Mechanism Deck and Main Board
2-3i Main Board ..............................
2-4. Cassette Lid...
2-5i Display Board i
2-6. Note for Installation

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SECTION 3 ADJUSTMENTS
3»l. Mechanical Adjustments .i
3-2i Electrical Adjustments u

SECTION 4 DIAGRAMS
4-1. Printed Wiring Board
4-2. Schematic Diagram i,
4-3, IC Block Diagrams ............................................................. 13
4-4. IC Pin Function

lC401 Tuner Controller/LCD Drive

(uPD1724GB-710-1A7) 19

SECTION 5 EXPLODED VIEWS
5-1, Cabinet and Board Section ....................
5-2. Mechanism Section (MF-WMFX305-43)

SECTION 6 ELECTRICAL PARTS LIST 22

HOW TO CHANGED THE CERAMIC FILTERS

This model is used two ceramic filters of CFZ, X2l You must used
same type of color marked ceramic filters in order to meet same
specifications

Therefore, the ceramic filter must changed two pieces together since
its supply two pieces in one package as a spare parts,

color mark
color mark Center Frequency

CF2 red 10.70MHZ
blue I 0,67MHz

col k
0,7, orange l0i73 MHz

0

X2 black 10.64MHZ
white 10.76MHz

Notes on chip component replacement

' Never reuse a disconnected chip component

- Notice that the minus side of a tantalum capacitor may be
damaged by heat.

Flexible Circuit Board Repairing

° Keep the temperature of soldering iron around 270°C during
repairing.

- Do not touch the soldering iron on the same conductor of the
circuit board (within 3 times).

' Be careful not to apply force on the conductor when soldering
or unsolden'ngi