Sony ST JX311 Service Manual

Page 1

ST-JX311/JX41L

SERVICE MANUAL

STJX311: This set is the tuner section in SEN-311.

US Model
Canadian Model
E Model
Australian Model

Photo: STJ X411

SPECIFICATIONS

FM tuner section
Tuning range
Antenna terminals

87.5 - 108 MHZ
75 ohms unbalanced
300 ohms balanced
Intermediate frequency
10.7 MHZ
Sensitivity (at 50 dB quieling )
22.1 dBf, 7 [JV (mono),
42.1 car, 70 (iv (stereo)
Usable sensitivity 19.5 dBf. 5 pV (lHF)
Signal-to-ncise ratio (at 75 kHz deviation)
80 dB (mono), 75 dB (stereo)

Harmonic distortion 0.3% (mono). 0.5% (stereo) at 1 kHz

Separation 40 dB at 1 kHz
Frequency response 30 Hz - 15 kHz 133133
Selectivity 55 dB at 400 kHz

AM suppression ratio 54 dB
Image response ratio 50 dB
lF response ratio 90 dB
Spurious response ratio
70 dB
Automatic tuning threshold
17.8 LN (30 dBt)
Output 775 mV, 4.7 konms (at 75 kHz deviation)
AM tuner section
Tuning range US, Canadian model: 530-1,710kHz (10kHz)
531 -1,710kHz (9kHz)
E, Australian model: 531 -1,602kHz

Antenna AM loop antenna, External antenna
terminal

Intermediate frequency
450 kHz

Usable sensitivity AM loop antenna: 500 uV/m (999 kHz or
1,000 kHz)

Signal-to»noise ratio 54 dB

Harmonic distortion 0.5%
Selectivity 35 dB (9 kHz)
38 dB (10 kHz)

General

Power requirements US, Canadian model: 120V AC, 60H:
E, Australian model: 240V AC, 50 Hz
Power consumption 8W (ST-JX411)

AC outlet (USA model only)

1 unswitched, 120W/1 A max,

Dimensions Approx. 430 x 80 x 295 mm (w/h/d)
(17 x 3m x 115/5 inches)
Weight ST~JX311: Approx. 21 kg (4 lb 110:)

ST-JX411: Approx. 26kg (51191202)
Accessories supplied
ST-JX311: Flat cord with 11-5-5-pin connectors (1),
connected to TC-W31l .
Flat cord with 9-9-pin connectors (1)
Remote commander RM-Sio2 (1)
Sony batteries SUM 3 (NS) (2)
Remote control cord (1)
Audio connecting cord (1)
AM loop antenna (1)
FM loop antenna (1)

ST-JX411 :

Design and specifications subject to change without notice.

FM STEREO/FM-AM TUNER
SONYFD

Page 2

ST-JX31 1/JX41 1

SAFETY CHECK-OUT

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-54OA. 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.

3. Measuring the voltage drop across a resistor by
means of a VOM or battery-operated 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
Part: on Set

AC
0.15MF €15! voltmeter
(0.75 V)

'%' Earth Ground

F lg. A. Using an AC voltmeter to check AC leakage.

SA FETV-R E LATED COMPONENT WARNING !!

COMPONENTS IDENTIFIED BV MARK A OR DOTTED
LINE WITH 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 PUE
LISHED BV SONY.

TABLE OF CONTENTS

Section Title Page
Specifications ................................. 1
Safety Check-out ............................... 2
SECTION 1. GENERAL
11. Location of Controls - 3
1-2. Connections ............................. 4
SECTION 2. ELECTRICAL ADJUSTMENTS 6
SECTION 3. DIAGRAMS
3-1. Printed Wiring Boards ~~~~~~~~~~~~~~~~~~~ 7
3-2. Scheinartic Diagram (Tuner Section) 11
3-3, Semiconductor Lead Layouts -~ .. l3
3-4~ waveforms .............................. 13
3-5. Schematic Diagram
(Control and Power Section) ----------- 14
SECTION 4. EXPLODED VIEW ............... 17
SECTION 5. ELECTRICAL PARTS LIST ------ 19

To change the AM tuning interval

The AM tuning interval is preset at the factory to 10 kHz

to match the frequency allocation system of your

country. To change the interval to 9 kHz, proceed as
follows.

1 Depress the POWER switch to turn on the unit.

2 Set the BAND FM/AM selector to AM.

3 Press the POWER switch to turn off the unit.

4 Hold the TUNING knob in the + " position. and
depress the POWER switch to turn on the unit.
To reset the interval to 10 kHz, follow the same
procedure,

Note

When the interval is changed, all preset stations which

you have memorized using the numeric buttons will be

erased from the memory. After changing the interval, be
sure to preset the stations again.

ATTENTION AUCOMPOSANT AVANT RAPPORT
A LA SECURITE!

LES composmrs IDENTIFIES PAR UNE MAROUE A
sun LES DIAGRAMMES SCHEMATIOUES er LA usre
DES PIECES sour can-muss POUR LA SECURITE
DE FONCTIONNEMENT. NE REMPLACER ces com.
POSANTS oue PAR DES PIECES souv DONT LES
NUMEROS sour ooNNés DANS cs MANUEL ou
DANS LES SUPPLEMENTS PUBLIES PAR SONY.

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