– 15 –
– 16 –
– 18 –
– 17 –
4-3. SCHEMATIC DIAGRAM
r
IC BLOCK DIAGRAM
IC1 TA8122AF
STEREO
DECODER
SW
HYS
ST
LED
TU
LED
FM
DET
VCO
PHASE
COM
PHASE
COM
FREQ.
DIVIDER
FM/AM
MONO SW
FM
IF
L
DET
AM
IF
PRE
AF
AM
OSC
FM
OSC
AM
MIX
FM
MIX
FM
RF
AM
RF
AM
DET
AM
AGC
1
24
23
22
21
20
18
17
16
15
14
13
2
3
4
5
6
7
8
9
10
11
12
19
AM RF IN
FM RF IN
GND1
FM MIX
AM MIX
AGC
VCC2
AM IF IN
FM IF IN
GND2
TUN LED
ST LED
QUAD
FM RF OUT
VCC1
FM OSC
AM OSC
DET OUT
MPX IN
LPF1
LPF2
VCO
L OUT
R OUT
WM-PA1
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
Ω
and
1
/
4
W or less unless otherwise
specified.
•
¢
: internal component.
•
: B+ Line.
•
: adjustment for repair.
• Power voltage is dc 3V and fed with regulated dc power
supply from external power voltage jack (J301).
• Voltages are dc with respect to ground under no-signal
(detuned) conditions.
no mark : FM
(
) : AM
<
> : PLAY
• Voltages are taken with a VOM (Input impedance 10 M
Ω
).
Voltage variations may be noted due to normal
production
tolerances.
• Signal path.
: FM
: PB
