Sony seq 300 service manual

Page 1

SERVICE MANUAL

US Model
Canadian Model
AEP Model

UK Model

E Model

PHOTO: US Model

SPECIFICATIONS

Inputs LINE IN: Phono jacks,
245 mV (-10 st), 50 k ohms
TAPE: Phono jacks,
245 mV (-10 (135), 50 k ohms
Outputs LINE OUT: Phono jacks,
245 mV (-10 st),
Load impedance: more than 10 k ohms
REC OUT: Phono jacks,
245 mV (-1O st),
Load impedance: more than 10 k ohms
Graphic equalizer
Boost/cut range: :10 dB
Center frequencies: 60 Hz, 150 Hz, 400 Hz.
1 kHz. 2.4 kHz. 6 kHz, 14kHZ
Frequency response (with EQUALIZATION ON)

LINE IN: 20 HZ to 40 kHz :?5 dB

Harmonic distortion
LINE IN: Less than 04008% (at 1 kHz, 1 V
Output)
Signal-to-noise ratio (with EQUALIZATION ON)
LINE IN: Better than 100 dB (A network,
1 V output)
Power requirements
US, Canadian MODEL: 120V AC, 60H:
AEP MODEL: 220V AC, ~50/60Hz
UK MODEL: 240V AC, ~50/60Hz
E MODEL: 1 10-120V/220-240V AC.
~50/60Hz

Power consumption

5 W
AC outlet 100 W, unswitched
Dimensions Approx. 430 X 80 X 245 mm (w/h/d)

(17 X 3% X 93/4 inches)

Weight Approx, 23 kg (5 lb 2 02)
Accessories supplied

Connecting cords (2)

SA FETY-RE LATED COMPONENT WARNING! I

COMPONENTS IDENTIFIED BY 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 PUB-
LISHED BY SONY.

ATTENTION AUCOMPO'SANT AYANT RAPPORT
A LA SECURITE!

LES COMPOSANTS IDENTIFIES PAR UNE MARQUE A
sun LES DIAGRAMMES SCHEMATIOUES ET LA LISTE
DES PIECES SONT camouzs POUR LA sécumTé
DE FONCTIONNEMENT. NE REMPLACER css com-
POSANTS QUE PAR DES PIECES souv DONT LES
NUMEROS SONT DoNNés DANS CE MANUEL ou
DANS LES SUPPLEMENTS PUBLIES PAR sonv.

GRAPHIC EIIUALIZER
SONE

Page 2

SEQ-300

MODEL IDENTIFICATION
-- Specification Label on Jack Plate -

SON-YE MODEL NO. SEQ-300
#

GRAPHIC EQUALIZER

SERIAL N0.
MADE IN JAPAN

US, Canadian model: AC 120V 60Hz 5W

AEP model: AC 220V ~50/60Hz 5W

UK model: AC 240V ~50/60Hz 5W

E model: AC 110-120V/220-240V
~50/60Hz 5W

SAFETY CH ECK-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 0.75 V, 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

AC

0.15uF §I.5kn / voltmeter
(0.75 V}

1.1" Earth Ground

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