Sony BM-87DST Marketing, Руководство по обслуживанию

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6-6. SCHEMATIC DIAGRAM (MAIN SECTION)
BM-87DST
Note:
• All capacitors are in
µ
F unless otherwise noted. pF:
µµ
F
50 WV or less are not indicated except for electrolytics
and tantalums.
• All resistors are in
Ω
and 1 /
4
W or less unless otherwise
specified.
•
U
: B+ Line.
• Power voltage is dc 9 V and fed with regulated dc power
supply from external power voltage jack (J103).
• Voltages and waveforms are dc with respect to ground
under no-signal conditions.
no mark
: STOP
LIS : LISTEN
FE : FAST-ERASE
REC : DICT/TEL-REC
F : FF
R : REW
FWD : LISTN, DICT, TEL, LTR
M-OFF : MOTOR OFF
M-ON : MOTOR ON
NO-CAS : NO CASSETTE
HU-LIS : LISTN mode (HU-80)
FOOT-LIS : LISTN mode (FS-75)
• Voltages are taken with a VOM (Input impedance 10 M
Ω
).
Voltage variations may be noted due to normal produc-
tion tolerances.
• Waveforms are taken with a oscilloscope.
Voltage variations may be noted due to normal produc-
tion tolerances.
• Circled numbers refer to waveforms.
• Signal path.
E
: PB
a
: REC
z
Waveforms
1
2
IC109
tl
X2
T101
VOLT/DIV : 0.5 V AC
TIME/DIV : 50 nsec
VOLT/DIV : 2 V AC
(X10ATT : ON)
TIME/DIV : 5
µ
sec
3 Vp-p
4.19 MHz
50 Vp-p
12.5
µ
sec