Sony bm 531 service manual

Page 1

531

SERVICE MANUAL

US Model

Canadian Model
AEP Model

UK Model

E Model

Tape

Recording system
Speaker

Tape speed
Frequency response
input

Output
Power output
Battery life (recording)

Power requirements

Dimensions

Weight
Accessories supplied

SPECIFICATIONS

_" (normal position 'YPE)

4-track 2-channel monaural

Approx 3.6 cm (1 7/16 inches) dia.

24 cm/s (15/16 ips). 1.2 cm/s (15/32 ips)

250 - 4,000 Hz (at 2.4 cm position)

Microphone jack (minijack) (PLUG lN POWER)

sensitivity 0.2 mV, for low impedance microphone

Earphone jack (minijack) for 8 ~ 300 ohm earphone

150 mW (at 10% harmonic distortion)

Sony SUM-3 (NS): Approx. 6 hours

Sony AMS (N): Approx. 17 hours

3V DC, two size AA (R6) batteries

DC tN 3V jack accepts:

- Sony AC-DZM AC power adaptor (not suppiled) lor
use on 120V AC, 60 Hz

- Sony 00070 car battery cord (not suppiled) tor use
with 12V car battery

Approx 67.5 x 124 x 27 mm (w/lvd)

(2 3/4 x 5 x 1 1/8 inches) incl. projecting parts and

controls

Approx. 180 9 (64 02.) incl. batteries

Handstrap (1) Carm'ng case (1)

Design and specifications subject to change without notice

Model Name Using Similar M-550V, M-740,
Mechanism M-750V
Tape Transport Mechanism Type MB-53i-l4

FEATURES

- One-touch dictating

- VOR (voice operated recording) system economizes on

tapes, batteries and your time.
- A choice of two tape speeds enables
recording.

up to 2 hours of

- Electronic indexing function assists in locating specific parts

of a dictationt
- 3-digit tape counter for indexing the tape
~ Pause switch instantly halts the tape.
- Quick review and instant edit
- 3-way power source capability
' Automatic shut~ott mechanism
. Microphone sensitivity selector

Note: Use only the recommended AC power
adaptor or car battery cord manulactured by Sony
Polarity ot the plugs 01 other manutacturers may
be ditterent.

contents

is?

Polarity of the
BM-531 plug

MICRUBASSETE momma
ONY;

Page 2

BM-531

PARTS IDENTIFICATION
Mic (microphone)lPLUG IN POWER jack

VOL (volume) control
PAUSE switch
MIC (builtoin microphone)

EAR (earphone) jack
Cassette holder w ./
DICT/BATT (dictating/battery) Indicator : '

O (dictating) button

E-lDX (electronic indexing) button

Tape counter and reset button
TAPE SPEED selector (left side)---e

DC iN 3V (external power input)_.__..
jack (left side)

Speaker
Battery compartment (rear)

MAINTENANCE

Cleaning the Head

Clean the tape head after every 10 hours of use for the
proper operation of the unit. Moisten a cotton swab or a soft
cloth with denatured alcohol, and wipe the parts shown
below.

Record/playback head
Capstan Erase head

Pinch-roller

Cleaning the Casing

Clean the case with a sott cloth slightly moistened with water
or a mild detergent solution. Do not use alcohol, benzine or
thinner as they may mar the finish.

F NOTE ON THE MICROCASSETTE

To protect cassettes from
accidental erasure

To reuse a cassette

To record on a cassette
with removed tabs,
cover each slot with a
piece of plastic tape.

when a recording is made,
the previous recording is
automatically erased. To
prevent erasure, break the
cassette tabs.

Break out and
remove the tab.

Plastic tape

This unit uses only standard Microcassettes. Non
standard cassettes cannot be used because their L"
dimension (see illustration) is different.

Only standard
Standard / Microcassettes have
,-; a small indentation
on side A.

Non standard

Approx. Approx.

@ll'® 5 mm 2.5 mm
_I. L L 1..
m7 1-

To erase the entire tape contents
Use the BE-2 or BEQH cassette eraser (sold separately).

CUE « [REVIEW » (tastiorward,
cue/review, rewind) switch

v (listen) button
: (stop/eject) button

MIC SENS (microphone sensitivity)
selector

VOR (voice operated recording) switch
Handstrap catch

Handstrap
(supplied)

SERVICING NOTE

Repairing printed resistor

Cut both sides of the resistor and solder the carbon resistor
having same value in place of printed one of the conductor
side.

1/4W carbon resistor is supplied for the replacing part of the
printed resistor.

Notes on chip component replacement

0 Never reuse a disconnected 'chip component.
0 Notice that the minus side ofa tantalum capacitor
may be damaged by heat.