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SLV-777HF/778HF/788HF RMT-V231B/V232B SERVICE MANUAL US Model Canadian Model SLV-777HF/778HF/788HF PX Model SLV-777HF Photo : SLV-788HF • Refer to the SERVICE MANUAL of VHS MECHANICAL ADJUSTMENT for MECHANICAL ADJUSTMENTS. S MECHANISM (9-921-647-11) SPECIFICATIONS VIDEO CASSETTE RECORDER MICROFILM...
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MARK ! ON THE SCHEMATIC DIAGRAMS AND IN THE PARTS CRITIQUES POUR LA SÉCURITÉ DE FONCTIONNEMENT. NE LIST ARE CRITICAL TO SAFE OPERATION. REPLACE THESE REMPLACER CES COMPOSANTS QUE PAR DES PIÈSES SONY COMPONENTS WITH SONY PARTS WHOSE PART NUMBERS DONT LES NUMÉROS SONT DONNÉS DANS CE MANUEL OU APPEAR AS SHOWN IN THIS MANUAL OR IN SUPPLEMENTS DANS LES SUPPÉMENTS PUBLIÉS PAR SONY.
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SAFETY CHECK-OUT After correcting the original service problem, perform the following safety checks before releasing the set to the customer. LEAKAGE TEST Check the area of your repair for unsoldered or poorly-soldered connections. Check the entire board surface for solder splashes and bridges.
SLV-777HF/778HF/788HF SERVICE 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.
HOW TO REPLACE A ROTARY UPPER DRUM (777HF, 778HFMODEL) See below for note. 2-1. HOW TO REMOVE A ROTARY UPPER DRUM 2-2. HOW TO ATTACH A NEW ROTARY UPPER Remove screw 1 (+P3 × 8) and remove the ground shaft DRUM assembly 2.
2-4. POWER BLOCK, MA-327 BOARD (WITH S MECHANISM DECK) Connector (From CN101 on power block) 2 Screws 3 Power block 4 Screws 5 MA-327 board (with S mechanism deck) 2-5. S MECHANISM DECK 1 Flexible board From CN260 on 2 Screws MA-327 board 4 Screws S mechanism deck...
SLV-777HF/778HF/788HF 3-3. SERVO/SYSTEM CONTROL BLOCK DIA GRAM MA-327 BOARD (SEE PAGE 4-8, 11, 22) CN104 RESET M12V IC160 (2/2) S DATA CHECK DRUM MOTOR IC160 &• REC/PB D109 D109 SYSTEM CONTROL S CLK CN101 D161 L161 M901 IC160 (1/2) AMP VCC...
SLV-777HF/778HF/788HF 3-5. MODE CONTROL BLOCK DIA GRAM FR-138 BOARD (SEE PAGE 4-25) IC420 FLUORESCENT MODE CONTROL INDICATOR TUBE SEG1 CN402 SEG16 -30V 27 VEE S CLK 0 S OUT 0 D IN S IN 0 D OUT JOG LED FLD CS...
SLV-777HF/778HF/788HF 3-6. TUNER BLOCK DIA GRAM MA-327 BOARD (SEE PAGE 4-19) SW12V SW5V L731 TU701 TU701 TUNER/MOD/IF TUNER/MOD/IF IF702 V OUT TU VIDEO IC201 32 VIDEO SPLITTER BLOCK IC733 (SEE PAGE 3-3) VHF/ ST/BILINGUAL PROCESSOR TU AUDIO L IC360 AUDIO...
SLV-777HF/778HF/788HF 4-2. PRINTED WIRING BOARDS AND SCHEMATIC DIAGRAMS MA-327 (REC/PB AMP, VIDEO, SERVO/SYSTEM CONTROL, AUDIO, TUNER) PRINTED WIRING BOARD There are few cases that the part printed on this diagram isn’t mounted in this model. — Ref. No.: MA-327 Board; 1,000 Series —...
SLV-777HF/778HF/788HF MA-327 (REC/PB AMP) SCHEMATIC DIAGRAM — Ref. No.: MA-327 Board; 1,000 Series — MA-327 BOARD THIS NOTE IS COMMON FOR PRINTED WIRING BOARDS AND SCHEMATIC DIAGRAMS. MA-327 BOARD IC260 4 REC (In addition to this, the necessary note is...
SLV-777HF/778HF/788HF MA-316 (POWER SUPPLY, AV-BUS) SCHEMATIC DIAGRAM • See page 4-3 for MA-327 BO ARD printed wiring boar d. — Ref. No.: MA-327 Board; 1,000 Series — POWER SUPPLY, AV-BUS 4-21 4-22 MA-327 (7/8) (8/8)
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SLV-777HF/778HF/788HF FR-138 (MODE CONTROL) PRINTED WIRING BOARD There are few cases that the part printed on this diagram isn’t mounted in this model. — Ref. No.: FR-138 Board; 2,000 Series — FR-138 BOARD MA-327 REC/PB AMP, VIDEO, AUDIO, CN401 SERVO/SYSTEM CONTROL,...
SLV-777HF/778HF/788HF DM-80 (OPERATION SWITCHES) PRINTED WIRING BOARD AND SCHEMATIC DIAGRAM JK-162 (LINE-2 IN) PRINTED WIRING BOARD AND SCHEMATIC DIAGRAM — Ref. No.: DM-80 Board; 2,000 Series — — Ref. No.: JK-162 Board; 2,000 Series — There are few cases that the part printed on this diagram isn’t mounted in this model.
SLV-777HF/778HF/788HF POWER BLOCK SR801 (SWITCHING REGULATOR) PRINTED WIRING BOARD AND SCHEMATIC DIAGRAM There are few cases that the part printed on this diagram isn’t mounted in this model. — Ref. No.: SR801 Board; 8,000 Series — POWER BLOCK (SR801) T101 POWER TRANSFORMER...
SLV-777HF/778HF/788HF POWER BLOCK SR709 (SWITCHING REGULATOR) PRINTED WIRING BOARD AND SCHEMATIC DIAGRAM There are few cases that the part printed on this diagram isn’t mounted in this model. — Ref. No.: SR709 Board; 9,000 Series — POWER BLOCK (SR709) T101 POWER TRANSFORMER...
5-3. SYSTEM CONTROL — SYSTEM CONTROL PERIPHERAL CIRCUIT INTERFACE (MA-327 board IC160) Signal Pin No. I/O level MA-327 Board RESET Normally “H”. “L” when service interruption detected or restored. IC160 $£ MA-327 Board Serial communication data to audio microprocessor and I2C DATA1 IC160 @™...
SLV-777HF/778HF/788HF SECTION 6 ADJUSTMENTS 6-1 MECHANICAL ADJUSTMENTS 2-1-3. Input Signal Check Video signal produced by a pattern generator is used as an adjustment signal to perform electrical alignment for this unit. This video signal For the mechanical adjustments, please refer to the must satisfy the specification.
2-1-5. Input/Output Levels and Impedance 2-2. POWER SUPPLY CHECK Video input: LINE IN 2-2-1. Output Voltage Check (MA-327 Board) Input signal: 1Vp-p, 75ohms, unbalanced, Mode sync negative Measuring Instrument Digital voltmeter Video output: LINE OUT SW 12V Check Output signal: 1Vp-p, 75ohms, unbalanced, IC601 pin 2 sync negative Measurement point...
2-3. SERVO SYSTEM CHECK Unless otherwise specified, set the switches to the following positions. • INPUT SELECT switch ..........LINE 1 • TAPE SPEED switch ............SP 2-3-1. RF Switching Position/ AF Switching Position Adjustments (MA-327 Board) [Adjustment Purpose] To adjust the link of the A-ch and B-ch of the tape playback outputs. To make the unit compatible with other tapes and units.
2-4. VIDEO SYSTEM CHECKS 2-4-2. SYNC AGC Check (MA-327 Board) For the video system checks, follow the checking procedures given Mode below as a rule. The color bar video signal supplied from the pattern Signal Color bar generator is used as the video input signal for the video system IC201 pin #•...
2-4-4. Recording Chroma Level Check 2-5. AUDIO SYSTEM ADJUSTMENT (MA-327 Board) • For the adjustment of the audio system, perform in the SP mode if there is no special notes. Use the alignment tape. Mode Recording (SP) Signal Color bar [Connecting Instruments] IC201 pin !¢...
2-5-3. Overall Output Level and Distortion Factor Check Mode Self-record playback Signal 400Hz, –7.5dBs : CJ570 Measurement point CJ570 Measuring instrument Audio level meter and Distortion meter Specified value Playback Level: –7.5 ± 3dBs Distortion: 4.0% or less [Check Method] 1) Input signal of 400Hz and –7.5dBs to the audio input.
SLV-777HF/778HF/788HF SECTION 7 REPAIR PARTS LIST 7-1. EXPLODED VIEWS NOTE: • -XX, -X mean standardized parts, so they may • The mechanical parts with no reference number The components identified by mark ! or have some differences from the original one.
7-1-4. MECHANISM DECK-2 Note: There are two types of drum assembly in the 777HF, #701 778HF models. [Discrimination] No. 768-770 (Note) —Top View— There are two printed circuit boards on the top. No. 776 #701 —Top View— There is no printed circuit board. #702 Note: It cannot be divided to two parts, the upper and the...
DM-80 FR-138 7-2. ELECTRICAL PARTS LIST NOTE: • Due to standardization, replacements in the • RESISTORS When indicating parts by reference number, parts list may be different from the parts All resistors are in ohms. please include the board name. specified in the diagrams or the components METAL: metal-film resistor The components identified by mark ! or...