Sony tcm 838 service manual

Page 1

TCM-828/838:

US Model
Canadian Model

SERVICE MANUAL

TOM-828:

AEP Model
UK Model
E Model

PHOTO: TOM-838

SPECIFICATIONS

Approx. 142 x 49 x 264 mm (w/h/d)
(55/. x1 /15 XIOS/g inches)

incl. projecting parts and controls

Approx. 800 g (1 lb 12 0:} incl. batteries

MT828 J

Z-track I-channel monaural Dimensions:
Approx. 7.7 cm (37. inches) dia.
Approx. 2 min. with Sony 060 cassette
504,000 Hz
Microphone input (minijacki

sensitivity 0.2mV (-72 dB)

for low impedance microphone
Earphone jack (minijack)

for 8 to soc-ohm earphone or load

impedance 10 kilohms or higher
Remote control jack
450 mW lat10% harmonic distortion)
6 V dc

Recording system:
Speaker:

Fast winding time:
Frequency response:
Input:

Weight:

Tape Transport Mechanism Type I
Output:
Other jock:

Power output:
Power requirements:

Battery life

4 batteries IEC designation R14 (size C)
240 V ac, 50 Hz (UK model)

120 V an, 60 Hz (US, Canadian model)
220 V ac, 50 Hz (AEP model)

120-220 V ac, 50 Hz (E model)

Batteries

Recording Playback

Sony New Super SUM-2 INS)
batteries or Evereadv No. 1235 4 4
Heavy Duty batteries

Eveready No, E93
Alkaline batteries

Sony Evereadv AMZ or

10 10

(hours)

SAFETY-RELATED COMPONENT WARNING

COMPONENTS IDENTIFIED BY SHADING AND MARK

A ON THE SCHEMATIC DIAGRAMS AND IN THE
PARTS LIST ARE CRITICAL TO SAFE OPERATION.
REPLACE THESE COMPONENTS WITH SONY PARTS
WHOSE PART NUMBERS APPEAR AS SHOWN IN THIS
MANUAL OR IN SUPPLEMENTS PUBLISHED BV SONY.

ATTENTION Au COMPOSANT AVANT RAPPORT
A LA sEcunnE!

LES COMPOSANTS IDENTIFIES PAR uNE TRAME ET
UNE MAROUE A son LES DIAGRAMMES SCHE-
MATIDUEs ET LA LISTE DEs PIECES SONT CRITIQUES
Poun LA SECURITE DE FONCTIONNEMENT. NE REM-
PLACER CES COMPOSANTS ouE PAR DES PIECES
SONY DONT LEs NUMEROS s0NT DONNEs DANS CE
MANUEL ou DANS LES SUPPLEMENTS PueLIEs PAR
SONV.

BASSETTE-CIIRDER

SONXC)

Page 2

SAFETY CHECK-OUT (US Model)

After correcting the original service problem,
perform the following safety check before releasing
the set to the customer:

Check the antenna terminals, metal trim, metallized
knobs, screws, and all other exposed metal parts for
AC leakage. Check leakage as described below.

LEAKAGE TEST

The AC leakage from any exposed metal part to
earth ground and from all exposed metal parts to any
exposed metal part having a return to chassis, must
not exceed 0.5 mA (500 microampers). Leakage
current can be measured by any one of three
methods.

1. A commercial leakage tester, such as the
Simpson 229 or RCA WT-540A. Follow the
manufacturers instructions to use these instru-
ments.

2. A battery~operated AC milliammeter. The Data
Precision 245 digital multimeter is suitable for
this job.

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MODEL IDENTIFICATION

sonva MODEL Na. W/l/ll/A -

CASSETTE - CORDER
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{

US, Canadian model:

3. Measuring the voltage drop across a resistor by
means of a VOM or batteryoperated AC volt-
meter. The limit indication is 0.75V, so
analog meters must have an accurate low-
voltage scale. The Simpson 250 and Sanwa
SH-63Trd are examples of a passive VOM that
is suitable. Nearly all battery operated digital
multimeters that have a 2V AC range are
suitable. (See Fig. A)

To Exposed Metal
Parts on Set

0.75M Ii gum

'é' Earth Ground

A C
/ Ira/[meter
(0 75 V}

Fig, A. Using an AC voltmeter to check AC leakage.

-¢-.-- --

TOM-828
TCM-838

AC: 120V60 Hz4W

AEP model: AC: 220 V 50 Hz 4 W
UK model: AC: 240 V 50 Hz 4 W
E model: AC: 120/220 V 50 Hz 4 W
SECTION 1
DISASSEMBLY

Non: Follow the diuaembly procedure In the numerleel order glven.

CABINET R EMOVAL

MECHANICAL BLOCK REMOVAL

L mechanical

9-0-