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SLV-M20HF
RMT-V250
US Model
Canadian Model
SERVICE MANUAL
VIDEO CASSETTE RECORDER
MICROFILM
S MECHANISM
· Refer to the SERVICE MANUAL of VHS MECHANICAL
ADJUSTMENT
for MECHANICAL ADJUSTMENTS.
(9-921-647-11)
G
j
SPECIFICATIONS
MC-Service


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-- 2 --
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 PAR UNE MARQUE
! SUR LES
DIAGRAMMES SCHÉMATIQUES 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.
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.
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. Follow the manufacturers' instructions to use these
instruments.
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 voltmeter. 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
Parts on Set
0.15
µF
1.5 k
AC
Voltmeter
(0.75 V)
Earth Ground
Fig. A. Using an AC voltmeter to check AC leakage.
[ NOTE ON REPAIRING HARNESSES BETWEEN AN-16/17
BOARDS AND MG-21 BOARD ]
Be sure to use the original one or equivalent (AWG, length).
If not so, the resonance frequency will be changed.
AN-16 board
MG-21 board
CN201
CN002
AN-17 board
MG-21 board
CN101
CN001


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SERVICE NOTE
1.
ERROR CODE INDICATION ··········································· 5
1.
GENERAL
Basic Operations
Playing a tape ········································································· 1-1
Recording TV programs ························································ 1-1
Locating a channel using the channel list ······························ 1-2
Recording TV programs using VCR Plus+ ··························· 1-3
Setting the timer manually ····················································· 1-3
Additional Operations
Playing/searching at various speeds ······································ 1-4
Searching for a selected point on the tape ····························· 1-5
Skip-searching automatically ················································· 1-5
Creating a favorite channel list ·············································· 1-6
Recording TV programs using the quick timer ····················· 1-6
Checking/changing/cancelling the manual timer settings ····· 1-6
Recording stereo and bilingual programs ······························ 1-7
Searching using the index function ········································ 1-8
Adjusting the picture ····························································· 1-8
Changing menu options ························································· 1-8
Editing with another VCR ····················································· 1-9
SmartFile function
About the SmartFile function ················································ 1-9
Recording using the SmartFile function ······························ 1-10
Selecting and playing a program ········································· 1-11
Checking the contents of a tape ··········································· 1-11
Labelling a recorded program and tape ······························· 1-11
Protecting a recorded program ············································· 1-13
Erasing the data of an unwanted program ··························· 1-13
Storing program data from the DSS receiver
(Program Data Download) ··················································· 1-13
GUIDE Plus+ system
About the GUIDE Plus+ system ·········································· 1-14
Overview of the GUIDE Plus+ menu ·································· 1-15
Using the Grid menu ···························································· 1-15
Using the Sort menu ···························································· 1-16
Using the Schedule menu ···················································· 1-17
Using the Editor menu ························································· 1-18
Using the Demo menu ························································· 1-19
Additional Information
Troubleshooting ··································································· 1-19
Index to parts and controls ··················································· 1-20
2.
DISASSEMBLY
2-1.
UPPER CASE,
FRONT PANEL BLOCK ASSEMBLY ·························· 2-1
2-2.
FR-139, DM-81, AJ-2, AN-17 BOARDS ······················· 2-1
2-3.
MG-21 BOARD, REAR PANEL ···································· 2-1
2-4.
POWER BLOCK, MA-335 BOARD
(WITH S MECHANISM DECK) ··································· 2-2
2-5.
AN-16 BOARD, S MECHANISM DECK ····················· 2-2
2-6.
INTERNAL VIEWS ························································ 2-3
2-7.
CIRCUIT BOARDS LOCATION ··································· 2-4
3.
BLOCK DIAGRAMS
3-1.
OVERALL BLOCK DIAGRAM ···································· 3-1
3-2.
VIDEO BLOCK DIAGRAM ·········································· 3-3
3-3.
SERVO/SYSTEM CONTROL BLOCK DIAGRAM ····· 3-5
3-4.
AUDIO BLOCK DIAGRAM ·········································· 3-7
3-5.
MODE CONTROL BLOCK DIAGRAM ······················· 3-9
3-6.
TUNER BLOCK DIAGRAM ······································· 3-11
3-7.
POWER SUPPLY BLOCK DIAGRAM ······················· 3-13
4.
PRINTED WIRING BOARDS AND
SCHEMATIC DIAGRAMS
4-1.
FRAME SCHEMATIC DIAGRAM ································ 4-1
4-2.
PRINTED WIRING BOARDS AND
SCHEMATIC DIAGRAMS ············································ 4-3
· MA-335 (REC/PB AMP, VIDEO, SERVO/SYSTEM
CONTROL, AUDIO, TUNER)
PRINTED WIRING BOARD ························· 4-3
· MA-335 (REC/PB AMP) SCHEMATIC DIAGRAM ·· 4-5
· MA-335 (VIDEO, NORMAL AUDIO)
SCHEMATIC DIAGRAM ······························ 4-8
· MA-335 (SERVO/SYSTEM CONTROL)
SCHEMATIC DIAGRAM ···························· 4-11
· MA-335 (ON SCREEN DISPLAY)
SCHEMATIC DIAGRAM ···························· 4-15
· MA-335 (DSF) SCHEMATIC DIAGRAM ················ 4-17
· MA-335 (AFM AUDIO)
SCHEMATIC DIAGRAM ···························· 4-19
· MA-335 (TUNER) SCHEMATIC DIAGRAM ·········· 4-21
· MA-335 (POWER SUPPLY)
SCHEMATIC DIAGRAM ···························· 4-23
· MA-335 (AV-BUS) SCHEMATIC DIAGRAM ········· 4-25
· FR-139 (MODE CONTROL)
PRINTED WIRING BOARD ······················· 4-27
· FR-139 (MODE CONTROL)
SCHEMATIC DIAGRAM ···························· 4-29
· DM-81 (OPERATION SWITCHES)
PRINTED WIRING BOARD AND
SCHEMATIC DIAGRAM ···························· 4-31
· AJ-2 (LINE-2 IN)
PRINTED WIRING BOARD AND
SCHEMATIC DIAGRAM ···························· 4-32
· AN-16 (INNER SMART FILE SENSOR/WRITER),
AN-17 (FRONT SMART FILE SENSOR)
PRINTED WIRING BOARDS AND
SCHEMATIC DIAGRAMS ·························· 4-33
· MG-21 (CONDUCTOR SIDE) (SMART FILE)
PRINTED WIRING BOARD ······················· 4-35
· MG-21 (COMPONENT SIDE) (SMART FILE)
PRINTED WIRING BOARD ······················· 4-37
· MG-21 (SMART FILE)
SCHEMATIC DIAGRAM ···························· 4-39
· MG-21 (GUIDE PLUS) (SMART FILE)
SCHEMATIC DIAGRAM ···························· 4-41
· MG-21 (VIDEO ENCODER) (SMART FILE)
SCHEMATIC DIAGRAM ···························· 4-43
· POWER BLOCK SR821 (SWITCHING REGULATOR)
PRINTED WIRING BOARD AND
SCHEMATIC DIAGRAM ···························· 4-45
5.
INTERFACE, IC PIN FUNCTION
DESCRIPTION
5-1.
SYSTEM CONTROL --
VIDEO BLOCK INTERFACE
(MA-335 BOARD IC161) ··············································· 5-1
5-2.
SYSTEM CONTROL --
SERVO PERIPHERAL CIRCUIT INTERFACE
(MA-335 BOARD IC161) ··············································· 5-1
5-3.
SYSTEM CONTROL --
MECHANISM INTERFACE
(MA-335 BOARD IC161) ··············································· 5-2
5-4.
SYSTEM CONTROL --
SYSTEM CONTROL PERIPHERAL
CIRCUIT INTERFACE (MA-335 BOARD IC161) ······· 5-2
5-5.
SYSTEM CONTROL --
AUDIO BLOCK INTERFACE
(MA-335 BOARD IC161) ··············································· 5-2
5-6.
SERVO/SYSTEM CONTROL MICROPROCESSOR
PIN FUNCTIONS (MA-335 BOARD IC161) ················ 5-3
5-7.
TUNER/TIMER MODE CONTROL PIN FUNCTIONS
(FR-139 BOARD IC460) ················································ 5-4
TABLE OF CONTENTS
MC-Service


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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. Input Signal Check ·························································· 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-335 Board) ························· 6-2
2-3.
SERVO SYSTEM CHECK ············································· 6-3
2-3-1. RF Switching Position/
AF Switching Position Adjustments (MA-335 Board) ··· 6-3
2-4.
VIDEO SYSTEM CHECKS ··········································· 6-4
2-4-1. X'tal OSC Check (MA-335 Board) ································· 6-4
2-4-2. SYNC AGC Check (MA-335 Board) ······························ 6-4
2-4-3. Recording Y Level Check (MA-335 Board) ··················· 6-4
2-4-4. Recording Chroma Level Check (MA-335 Board) ········· 6-5
2-4-5. Playback Level Check (MA-335 Board) ························· 6-5
2-5.
AUDIO SYSTEM ADJUSTMENT ································· 6-5
2-5-1. ACE Head Adjustment ···················································· 6-5
2-5-2. E-E Output Level Check ················································· 6-5
2-5-3. Overall Output Level and Distortion Factor Check ········· 6-6
2-5-4. Overall Noise Level Check ·············································· 6-6
2-6.
TUNER SYSTEM ADJUSTMENT ································ 6-6
2-6-1. Separation Adjustment (MA-335 Board) ························ 6-6
2-7.
ADJUSTING PARTS LOCATION DIAGRAM ············· 6-8
7.
REPAIR PARTS LIST
7-1.
EXPLODED VIEWS ······················································ 7-1
7-1-1. FRONT PANEL ASSEMBLY AND UPPER CASE
SECTION ········································································ 7-1
7-1-2. CHASSIS SECTION ······················································· 7-2
7-1-3. MECHANISM DECK-1 ················································· 7-3
7-1-4. MECHANISM DECK-2 ················································· 7-4
7-1-5. MECHANISM DECK-3 ················································· 7-5
7-2.
ELECTRICAL PARTS LIST ·········································· 7-6


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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."
ERROR CODE
MODE CODE
0
Power-on eject
10 FWD x1
20 REW play
1
Power-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
Power-on stop
18 Power-off initial
28 Cas. loading
9
PB
19 Mecha. error (Power off)
(No auto PB check)
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
SLV-M20HF
SERVICE NOTE
Mode code indication when the error has occurred.
Error code
MC-Service