Sony cdp 791 service manual

Page 2

CDP1791/X11 1 ES

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-S4OA. 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 Ilimit" 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 Expared Metal
Part: on Set

[--
0.15uF L 1.5Hl /

'___l

'3 Earth Ground

A C
voltmeter

[0.75 W

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

SAFETY-RELATED COMPONENT WARNING

COMPONENTS IDENTIFIED BY MARK A 0R DOTTED
LINE WITH MARK A ON THE SCHEMATIC DIAGRAMS
AND IN THE PARTS LIST ARE CRITICAL T0 SAFE
OPERATION. REPLACE THESE COMPONENTS WITH
SONY PARTS WHOSE PART NUMBERS APPEAR AS
SHOWN IN THIS MANUAL OR IN SUPPLEMENTS PUB-
LISHED BY SONY.

MODEL IDENTIFICATION

, GDP-791
-Model Number Label--

CDP-X1 1 1 ES

MODEL No. V////////////A

SERIAL No.

WW

MADE IN JAPAN

MADE m FRANCE
us Model: A0120v 60H212W
Canadian Modal: AC;120V 60 Hz 12W
AEPMadel: A0220 - 230V. 50/60Hz
UK Modal: AC24OV~50I 60Hz

TABLE OF CONTENTS

Section M Page
Specifications ............................ 1
Safety Checkout ................. 2
Model Identification ........................... 2
1. GENERAL
Notes on Handling the Optical Pickup .
Block or Base Unit --------------- 3
Notes on Laser Diode Emission Check ~ 3
Location of Controls -------------- 3
Adjusting Operating Voltage -------------- 3
2_ DISASSEMBLY ......................... 4

3. ELECTRICAL BLOCK CHECKING

3 Curve Check ...................
RF Level Check - - , -
E-F Balance Check
RF PLL Freenm Frequency Check
Focus/1 tacking Gain -----------

4. DIAGRAMS
lClOl(CXA137ZQ)PIN DESCRIPTIONS - - ~ . 7

4-1. Block Diagram .................
4-2. Printed Wiring Boards ~ ~ -

4-3, Schematic Diagram ....................... 15
5. EXPLODED VIEWS ------- 21
6. ELECTRICAL PARTS LIST ------------ 24

ATTENTION AU COMPOSANT AVANT RAPPORT
A LA SECURITE!

LES COMPOSANTS IDENTIFIES PAR UNE manque A
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POSANTS ouE PAR DES PIECES sonv DONT LES
NUMEROS SONT DONNés DANS cc MANUEL ou
DANS LES SUPPLEMENTS PUBLIES PAR soNv.