Sony SLV-789HF - Video Cassette Recorder, Service Manual

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4-1
SLV-789HF/792HF/799HF
SECTION 4
PRINTED WIRING BOARDS AND SCHEMATIC DIAGRAMS
(For printed wiring boards)
•
b
: Pattern from the side which enables seeing.
(The other layers' patterns are not indicated.)
• Through hole is omitted.
• Circled numbers refer to waveforms.
• There are few cases that the part printed on diagram
isn’t mounted in this model.
• Chip parts.
(For schematic diagrams)
• All capacitors are in
µ
F unless otherwise noted. pF :
µµ
F.
50V or less are not indicated except for electrolytics and
tantalums.
• Chip resistors are 1/10W unless otherwise noted.
k
Ω
=1000
Ω
, M
Ω
=1000k
Ω
.
• Caution when replacing chip parts.
New parts must be attached after removal of chip.
Be careful not to heat the minus side of tantalum capacitor, Be-
cause it is damaged by the heat.
• Some chip part will be indicated as follows.
Example C541 L452
22U 10UH
TA A 2520
• Constants of resistors, capacitors, ICs and etc with XX indicate
that they are not used.
In such cases, the unused circuits may be indicated.
• Parts with
★
differ according to the model/destination.
Refer to the mount table for each function.
• All variable and adjustable resistors have characteristic curve B,
unless otherwise noted.
• Signal name
XEDIT
→
EDIT PB/XREC
→
PB/REC
•
2
: non flammable resistor
•
1
: fusible resistor
•
C
: panel designation
• : internal component.
• U : B+ Line.
•
V
: B– Line.
• Circled numbers refer to waveforms.
• Readings are taken with a color-bar signal input.
• Voltage are dc between ground and measurement points.
• Readings are taken with a digital multimeter (DC10M
Ω
).
• Voltage variations may be noted due to normal production
tolerances.
• C : adjustment for repair.
• Circled numbers refer to waveforms.
THIS NOTE IS COMMON FOR PRINTED WIRING
BOARDS AND SCHEMATIC DIAGRAMS.
(In addition to this, the necessary note is
printed in each block.)
C
B E
5 6 4
2 1 3
5 4 6
2 3 1
4 5
2 3 1
1 2
4 5 3
3
2 1
3
2 1
3
2 1
Transistor
Diode
Kinds of capacitor
Temperature characteristics
External dimensions (mm)
When indicating parts by reference
number, please include the board name.
Note :
The components identified by
mark
! or dotted line with mark
! are critical for safety.
Replace only with part number
specified.
Note :
Les composants identifiés par
une marque
! sont critiques
pour la sécurité.
Ne les remplacer que par une
pièce portant le numéro spécifié.