TCM-450DV
12
12
IC101 BH3682FV
5-5. IC BLOCK DIAGRAMS
IC601 LB1979VL-TLM-E
Note on schematic diagrams
• 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 W and
1
/
4
W or less unless otherwise specified.
•
A
: B+ Line.
•
H
: adjustment for repair.
• Power voltage is dc 3V and fed with regulated dc power supply
frombattery terminal .
• Voltages are dc with respect to ground under no-signal conditions.
no mark : PLAY
( ) : REC
• Signal path.
E
: PB
a
: REC
• Voltages are taken with a VOM (Input impedance 10 M
Ω
).
Voltage variations may be noted due to normal production toler-
ances.
• Circled numbers refer to waveforms.
12
11
10
9
8
7
6
5
4
3
1
13
14
15
16
17
18
19
20
21
22
23
24
PREVCC
PREINF
RFL
TOUT
RFL
TIN
REG
PRE1OUT
MICALCIN
VOR
TA
U
VORC
VORIN
VOROUT
REC/BIAS
REC/SP2OUT
PWRVCC
PREIIN
GND
ALCNF
VORCTRL
MICALCOUT
ALCT
AU
ALCDETIN
REC/SPIN
REC/SP1OUT
SPGND
BH3682FV
TapeRecorder
PRE/PWR
MIC/REC
PREVCC
PWRCTRL
PRE1
31dB
MICALC/PRE2
delta: 40dB
BIAS
26dB
PWRVCC
INV
VORCTRL
PRE
PWR
POM
37dB
REC/POWER
22dBSE
0dBSE
REC
ALC
REG
RBC
VOR
RIPL
2
+
-
+
-
ZZ
INV
2
3
5
4
6
7
8
9
10
1
11
12
13
14
15
16
17
18
19
20
SOFT
SW
MIX
CURRENT/MOTIVE
LOGIC
WAVEFORM
DETECT
PRE
DRIVER
OUTPUT
CURRENT DETECT
SPEED
DETECT
REFERENCE VOLTAGE
FOR SPEED CONTROL
POWER SUPPLY
BIAS
REFERENCE
VOLTAGE
OSCILLATOR
CIRCUIT
MOTIVE POWER
DETECT
+
–
FC GND
FC
RI
OUT
VSP
IN+
VREF
S/S
COM
OSC
WB
VCC
NC
U OUT
V OUT
W OUT
P-GND
VB
UB
GND
• WAVEFORMS
IC601
qa
OSC
VOL/DIV : 20m V AC
TIME/DIV : 0.5 msec
1
40mVp-p
1.6msec
