Sony SLV-772HF, SLV-779HF Service Manual

SLV-772HF/ 779HF

RMT-V266

SERVICE MANUAL

G
j

Photo: SLV-779HF

RMT-V266

Refer to the SERVICE MANUAL of VHS
MECHANICAL ADJUSTMENT
MECHANICAL ADJUSTMENTS. (9-921-647-11)

for

SPECIFICATIONS

US Model

SLV-779HF

Canadian Model

SLV-772HF/779HF

S MECHANISM

MICROFILM

VIDEO CASSETTE RECORDER

SAFETY CHECK-OUT

After correcting the original service problem, perform the following
safety checks before releasing the set to the customer.

1. Check the area of your repair for unsoldered or poorly-soldered
connections. Check the entire board surface for solder splashes
and bridges.

2. Check the interboard wiring to ensure that no wires are
"pinched" or contact high-wattage resistors.

3. Look for unauthorized replacement parts, particularly
transistors, that were installed during a previous repair . Point
them out to the customer and recommend their replacement.

4. Look for parts which, though functioning, show obvious signs
of deterioration. Point them out to the customer and
recommend their replacement.

5. Check the line cord for cracks and abrasion.
Recommend the replacement of any such line cord to the
customer.

6. Check the B+ voltage to see it is at the values specified.

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

T o Exposed Metal

Parts on Set

AC

0.15

µ

F

1.5 k

Ω

Voltmeter
(0.75 V)

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 0.5mA (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
TW-540A. Follo w the manufacturers' instructions to use these
instruments.

2. A battery-operated A C 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 v oltmeter. The "limit" indication
is 0.75V, so analog meters must have an accurate lo w v oltage
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 A C range are suitable. (See
Fig. A)

Earth Ground

Fig. A. Using an A C v oltmeter to check A C leakage.

SAFETY-RELATED COMPONENT WARNING!!

COMPONENTS IDENTIFIED BY MARK ! OR DOTTED LINE WITH
MARK ! 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 BY SONY.

ATTENTION AU COMPOSANT AYANT RAPPORT

À LA SÉCURITÉ!
LES COMPOSANTS IDENTIFÉS P AR UNE MARQUE ! SUR LES
DIAGRAMMES SCHÉMA TIQUES ET LA LISTE DES PIÈCES SONT
CRITIQUES POUR LA SÉCURITÉ DE FONCTIONNEMENT. NE
REMPLACER CES COMPOSANTS QUE PAR DES PIÈSES SONY
DONT LES NUMÉROS SONT DONNÉS DANS CE MANUEL OU
DANS LES SUPPÉMENTS PUBLIÉS PAR SONY.

— 2 —

TABLE OF CONTENTS

SERVICE NOTE

1. ERROR CODE INDICATION··········································· 4

1. GENERAL

Getting Started

Unpacking ···········································································1-1
Setting up the remote commander·······································1-1
Hookups ··············································································1-2
Selecting a language···························································· 1-8
Setting the clock ··································································1-9
Setting up the cable box control ········································1-10
Presetting channels ····························································1-12
Setting up the VCR Plus+ system ·····································1-14

Basic Operations

Playing a tape ····································································1-14
Recording TV programs ····················································1-15
Recording TV programs using the VCR Plus+ system····· 1-16
Setting the timer manually ················································1-17

Additional Operations

Playing/searching at various speeds··································1-18
Searching for a selected point on the tape························· 1-18
Skip-searching automatically ············································1-19
Setting the recording duration time···································1-19
Checking/changing/canceling timer settings·····················1-19
Recording stereo and bilingual programs ·························1-20
Adjusting the picture ·························································1-20
Changing menu options·····················································1-21
Editing with another VCR················································· 1-21

Additional information

General setup information ·················································1-22
Index to parts and controls ················································1-22

• MA-341 (6/7) (MODE CONTROL) SCHEMATIC
DIAGRAM ································································4-17

• MA-341 (7/7) (POWER SUPPLY) SCHEMATIC
DIAGRAM ································································4-19

• DM-84 (TAPE OPARATION) PRINTED
WIRING BOARD ·····················································4-22

• DM-84 (TAPE OPARATION) SCHEMATIC
DIAGRAM ································································4-22

• MF-316 (POWER/EJECT SWITCH)
SCHEMATIC DIAGRAM·········································4-23

• MF-316 (POWER/EJECT SWITCH) PRINTED
WIRING BOARD ·····················································4-24

5. INTERFACE, IC PIN FUNCTION
DESCRIPTION

5-1. SYSTEM CONTROL — MECHANISM BLOCK

INTERFACE (MA-341 BOARD IC160) ························ 5-1

5-2. SYSTEM CONTROL — SERVO PERIPHERAL

CIRCUIT INTERFACE (MA-341 BOARD IC160) ·······5-1

5-3. SYSTEM CONTROL — SYSTEM CONTROL

PERIPHERAL CIRCUIT INTERFACE
(MA-341 BOARD IC160)···············································5-2

5-4. SYSTEM CONTROL AND RF MODULATOR

— INPUT SELECTION BLOCK INTERFACE
(MA-341 BOARD IC160)···············································5-2

5-5. SYSTEM CONTROL — VIDEO/RP BLOCK

INTERFACE (MA-341 BOARD IC160) ························ 5-2

5-6. SYSTEM CONTROL — AUDIO BLOCK

INTERFACE (MA-341 BOARD IC160) ························ 5-2

5-7. SERVO/SYSTEM CONTROL MICROPROCESSOR PIN

FUNCTIONS (MA-341 BOARD IC160) ·······················5-3

2. DISASSEMBLY

2-1. CASE, FRONT PANEL BLOCK ASSEMBLY ··············2-1
2-2. MF-316 BOARD, DM-84 BOARD ································2-1
2-3. REAR PANEL ·································································2-2
2-4. MA-341 BOARD ····························································2-2
2-5. MECHANISM DECK····················································· 2-3
2-6. INTERNAL VIEWS························································2-4
2-7. CIRCUIT BOARDS LOCATION ···································2-5

3. BLOCK DIAGRAMS

3-1. OVERALL BLOCK DIAGRAM ····································3-1
3-2. VIDEO BLOCK DIAGRAM ··········································3-3
3-3. SERVO/SYSTEM CONTROL/TUNER

BLOCK DIAGRAM ·······················································3-5
3-4. AUDIO BLOCK DIAGRAM ··········································3-7
3-5. POWER BLOCK DIAGRAM········································· 3-9

4. PRINTED WIRING BOARDS AND

SCHEMATIC DIAGRAMS

4-1. FRAME SCHEMATIC DIAGRAM································4-3
4-2. PRINTED WIRING BOARDS AND SCHEMATIC

DIAGRAMS···································································· 4-5

• MA-341 (VUDEO, AUDIO, SERVO/SYSTEM
CONTROL, TUNER, POWER SUPPLY) PRINTED
WIRING BOARD ·······················································4-5

• MA-341 (1/7) (VIDEO) SCHEMATIC
DIAGRAM ··································································4-7

• MA-341 (2/7) (AUDIO) SCHEMATIC
DIAGRAM ··································································4-9

• MA-341 (3/7) (SERVO/SYSTEM CONTROL)
SCHEMATIC DIAGRAM·········································4-11

• MA-341 (4/7) (AUDIO PROCESS) SCHEMATIC
DIAGRAM ································································4-13

• MA-341 (5/7) (TUNER) SCHEMATIC
DIAGRAM ································································4-15

6. ADJUSTMENTS

6-1 MECHANICAL ADJUSTMENTS ·································6-1
6-2. ELECTRICAL ADJUSTMENTS ···································6-1
2-1. PREPARATION BEFORE ADJUSTMENT ···················6-1
2-1-1.Equipment Required ························································6-1
2-1-2.Equipment Connection ····················································6-1
2-1-3.Set-up of Adjustment·······················································6-1
2-1-4.Alignment Tape ·······························································6-1
2-1-5.Input/Output Levels and Impedance ······························· 6-2
2-1-6.Adjustment Sequence ······················································6-2
2-2. POWER SUPPLY CHECK ·············································6-2
2-2-1.Output Voltage Check (MA-341 Board) ·························6-2
2-3. SERVO SYSTEM CHECK ·············································6-3
2-3-1.RF Switching Position Adjustment

(MA-341 Board)······························································6-3
2-4. AUDIO SYSTEM ADJUSTMENT·································6-3
2-4-1.Hi-Fi Audio System Adjustment ·····································6-3

(Hi-Fi model only)···························································6-3
2-4-2.HiFi Switching Position Adjustment

(MA-341 Board)······························································6-4
2-4-3.Normal Audio System Adjustment··································6-4
2-4-4.ACE Head Adjustment ···················································· 6-4
2-4-5.E-E Output Level Check ·················································6-4
2-4-6.Frequency Response Check·············································6-4
2-5. ADJUSTING PARTS LOCATION DIAGRAM ·············6-6

7. REPAIR PARTS LIST

7-1 EXPLODED VIEWS ······················································ 7-1
7-1-1.FRONT PANEL AND UPPER CASE SECTION ··········7-1
7-1-2.CHASSIS SECTION·······················································7-2
7-1-3.MECHANISM DECK SECTION-1 ·······························7-3
7-1-4.MECHANISM DECK SECTION-2 ·······························7-4
7-1-5.MECHANISM DECK SECTION-3 ·······························7-5
7-2. ELECTRICAL PARTS LIST ··········································7-6

— 3 —

SER VICE NOTE

1. ERROR CODE INDICATION

• Error codes are indicated using the lower 5 digits in the fluorescent display tube.
“At this time, Colon “:” between character is not indicated.”

Mode code indication when the error has occurred.

Error code

ERROR CODE

0 No error
1 Cam encoder error Loading direction
2 Cam encoder error Unloading direction
3 T reel error
4 S reel error
5 Capstan error
6 Drum error
7 Error on initializing
8 Cassette loading error
9 Reserve

MODE CODE

0 Power-on eject 10 FWD x1 20 REW play
1 P ower-on initial 11 FWD x2 21 Cas. loading
2 Power-off eject 12 CUE 22 Tape loading
3 Power-off stop 13 PB-pause 23 Power-off loading
4 FF 14 RVS-pause 24 Mecha. error (Power on)
5 REW 15 RVS x1 25 Power-on eject initial
6 REC 16 RVS x2 26 Power-off eject initial
7 REC- pause 17 REV 27 APC REC
8 P ower-on stop 18 Power-off initial 28 Cas. loading
9 PB 19 Mecha. error (Power off) (No auto PB check)

— 4 —

SECTION 1

GENERAL

SLV-772HF/779HF

This section is extracted from
instruction manual.

1-1

1-2

1-3

1-4

1-5

1-6

1-7

1-8

1-9

1-10

1-11

1-12

1-13

1-14

1-15

1-16

1-17

1-18