SRF-M73
– 7 –
– 8 –
– 9 –
– MAIN BOARD (Component Side) –
Adjustment Location:
– MAIN BOARD (Conductor Side) –
L4
AM VCO Voltage Adjustment
RT1
FM Free-Run Adjustment
CT1
AM Tracking Adjustment
L1
AM Tracking Adjustment
T1
AM IF Adjustment
FM Tracking Adjustment
CT2
L2
TP
(MPX)
TP
(FM IN)
TP
(VT)
J1
SECTION 5
DIAGRAMS
5-1.
BLOCK DIAGRAM
18
20
16
13
19
24
22
FM
FRONT-END
FM IF AMP/
DISCRI
DECODER
AMP
SWITCH
BASS
BOOST
CONTROL
POWER
AMP
DET
REGULATOR
1/2
COUNTER
1/2
COUNTER
AM IF AMP/
DET
TUNING
INDICATOR
PD1
VCO
PD2
AM
FRONT-END
14
FM RF
IN
FM/AM
MIX OUT
CF3: US
CF4, 5: PANAMA
10.7MHz
CF1
10.7MHz
BASS BOOST AMP
IC2
SYSTEM CONTROLLER,
LIQUID CRYSTAL DISPLAY DRIVER,
KEY CONTROL
IC101
EEPROM
IC105
CF2
450kHz
FM
RF
26
FM DISCRI
FM
IF IN
6
7
21
5
1
2
14
13
L-CH
OUT
R-CH
OUT
4
27
29
1
2
3
ST IND
AM
IF IN
PILOT DET
LPF2
12
TUNE IND
9
AFC1/AGC
15
BAND
SELECT
PILOT DET
LPF1
PLL
LPF1
PLL
LPF2
VCO
AM OSC
FM OSC
AM RF
IN
FM/AM FRONT-END,
FM/AM DET, MPX
IC1
RT1
FM FREE-RUN
L4
AM VCO VOLTAGE
CT2, L2
FM TRACKING
S1
FM SENS
T1
AM IF
CT1, L1
AM TRACKING
L.P.F.
B.P.F.
BPF1
FM VCO
BUFFER
Q1
FM/AM BAND
SELECT SWITCH
Q3
COMPARATOR
IC4 (1/2)
LIQUID CRYSTAL DISPLAY
LCD101
VOLTAGE
DETECT
IC102
B+ SWITCH
Q104
DC/DC
CONVERTER
Q103, T101
B+ SWITCH
Q6
AM IF
BUFFER
Q4, 5
LOW-PASS
FILTER
Q101
• SIGNAL PATH
: FM
: AM
05
POWER
AMP
MUTE
CONTROL
RIPPLE FILTER
Q2
KEY MATRIX
S101 – 111, 113 – 116
KS0 – KS3
KR0 – KR3
X101
75kHz
SYSTEM CONTROLLER (IC101),
EEPROM (IC105) B+
FM/AM TUNER (IC1),
HEADPHONE AMP (IC3) B+
BASS BOOST AMP (IC2) B+
PLL LOW-PASS FILTER CIRCUIT B+
AM IF AMP CIRCUIT B+
D105
–1
–2
IN1
IN2
HEADPHONE AMP
IC3
2
4
IN1
IN2
OUT1
OUT2
9
7
OUT1
OUT2
LP
GAIN
B+
VREF
5
6
7
COMPARATOR
IC4 (2/2)
3
2
1
B+
CT1
D1-1
L1
AM FERRITE-ROD
ANTENNA
L2
FM RF
(PANAMA)
POWER
XOUT
XIN
IF ON
CE
DET
IN
MT/SW
REG
VCC
AM IF IN
EO
VCOL
VCOH
BAND
CMP IN
24
D
ATA
15
CK
14
2
1
CS
SK
3
DI
4
DO
CS
16
25
2 1
50
6
12
10
53
MUTE
5
BEEP
52
3
17
21
20
19
DX
LOCAL
S2
MEGA
BASS
ON
OFF
D1-2
D3
CT2
D2
L4
AM OSC
L3
FM OSC
RV1
VOL
J1
(HEADPHONE)
2
+
DRY BATTERY
SIZE “AAA”
(IEC DESIGNATION R03)
2PCS. 3V
10 – 13
6 – 9
COM0 – COM3
31 – 34
SEG0 – SEG14
35 – 49
