Printed Wiring Board -Key Section - Sony TAM-100 Service Manual

THIS NOTE IS COMMON FOR PRINTED WIRING
BOARDS AND SCHEMATIC DIAGRAMS.
(In addition to this, the necessary note is printed in each
block.)
For schematic diagrams.
Note:
• All capacitors are in µF unless otherwise noted. pF: µµF
50 WV or less are not indicated except for electrolytics
and tantalums.
• All resistors are in and 1 / W or less unless otherwise
4
specified.
• : internal component.
¢
• C : panel designation.
• U : B+ Line.
• Voltage and waveforms are dc with respect to ground
under no-signal conditions.
no mark : Add to DC 12V and fed with regulated dc power
supply from external power voltage jack.
: Impossible to measure
• Indication of transistor
C
Q
These are omitted
B E
• Voltages are taken with a VOM (Input impedance 10 M ).
Voltage variations may be noted due to normal production tol-
erances.
• Waveforms are taken with a oscilloscope.
Voltage variations may be noted due to normal production tol-
erances.
• Circled numbers refer to waveforms.
• Signal path.
F
: AUDIO
• Abbreviation
CND : Canadian model
For printed wiring boards.
Note:
•
: carbon pattern
• X : parts extracted from the component side.
• ¢ : internal component.
• b : Pattern from the side which enables seeing.
• Waveform
1
5.6Vp-p
4MHz
U1 !§ (XOUT)
– 7 –
2-2. PRINTED WIRING BOARD — KEY SECTION —
KEY BOARD
MEMO
16
ERASE
1
GREETING
SET/REC
MAIL BOX3
MAIL BOX2
SLOW/
REPEAT
1
MAIL BOX1
PLAY/STOP
09
9
ANSWER
ON/OFF
8
LED5
TIME
VOL+
VOL-
QUICK/SKIP
W1
1-673-413-
MAIN BOARD
A
(Page 8)
– 8 –
TAM-100
27
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