Sony SRF-M80 Service Manual ▷ View online
SRF-M80
4
Note:
Follow the disassembly procedure in the numerical order given.
2-2.
CABINET (FRONT) ASSY
• This set can be disassembled in the order shown below.
2-1.
DISASSEMBLY FLOW
SECTION 2
DISASSEMBLY
2-2. Cabinet (Front) Assy
(Page 4)
2-3. MAIN Board
(Page 5)
SET
2
five screws
(B1.7
(B1.7
×
6)
1
Open the battery case lid.
4
3
two claws
5
rubber key switch
(preset)
(preset)
6
cabinet (front) assy
adaptor (hold)
key board
S117
Note: When installing the cabinet (front) assy, adjust S117 and the adaptor (hold).
SRF-M80
5
2-3.
MAIN BOARD
Note: When installing the main board, adjust S1 and the adaptor (sens).
5
claw
adaptor (sens)
5
claw
6
main board
S1
3
holder (H/P)
key board
4
Remove two solders.
2
screw
(B1.7
(B1.7
×
6)
1
knob (vol)
6
SRF-M80
AM IF ADJUSTMENT
Adjust for a maximum reading on level meter
RV1
999 kHz
AM VCO VOLTAGE ADJUSTMENT
Adjustment Part
Frequency Display
Reading on Digital Voltmeter
L2
531 kHz
2.5
± 0.1 V
Confirmation
1602 kHz
8.6
± 0.3 V
AM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter
L1
621 kHz
CT1
1,404 kHz
FM VCO VOLTAGE CONFIRMATION
Frequency Display
Reading on Digital Voltmeter
87.5 MHz
8.3
± 0.3 V
108 MHz
13.6
± 0.3 V
FM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter
L3
98.0 MHz
Adjustment Location: MAIN board (See page 7)
FM STEREO ADJUSTMENT
Setting:
BAND button: FM
BAND button: FM
1. Connect the frequency counter to TP (FM ST) and TP (+B) as
shown the figure below.
2. Tune the set to 87.5 MHz.
3. Adjust RV2 for 75.9 to 76.1 kHz reading on the frequency
3. Adjust RV2 for 75.9 to 76.1 kHz reading on the frequency
counter.
Adjustment Location: MAIN board (See page 7)
0 dB=1
µ
V
[AM]
Setting:
BAND button : AM
BAND button : AM
[FM/TV]
Setting:
BAND button: FM
BAND button: FM
• Repeat the procedures in each adjustment several times, and the
tracking adjustments should be finally done by the trimmer ca-
pacitors.
pacitors.
• Remove FM antenna in FM adjustment.
AM RF signal
generator
30% amplitude
modulation by
400 Hz signal
Output level:
as low as possible
modulation by
400 Hz signal
Output level:
as low as possible
Put the lead-wire
antenna close to
the set.
antenna close to
the set.
+
–
–
level meter
set
16
Ω
i
jack (J1)
digital voltmeter
TP (VT)
TP (FM GND)
100 k
Ω
MAIN board
SECTION 3
ELECTRICAL ADJUSTMENTS
set
MAIN board
TP (FM IN)
TP (FM IN)
MAIN board
TP (FM GND)
TP (FM GND)
0.01
µ
F
Carrier frequency : 87.5 MHz
Modulation
Modulation
: no modulation
Output level
: 0.1 V (100 dB)
FM RF SSG
33 k
Ω
+
+
–
–
MAIN board
TP (FM ST)
TP (+B)
TP (FM GND)
frequency counter
1
µ
F/50 V
digital voltmeter
TP (VT)
TP (AM GND)
100 k
Ω
MAIN board
FM RF signal
generator
22.5 kHz frequency
deviation by 400 Hz
signal
Output level:
as low as possible
deviation by 400 Hz
signal
Output level:
as low as possible
+
–
–
level meter
i
jack (J1)
set
MAIN board
TP (FM IN)
TP (FM IN)
MAIN board
TP (FM GND)
TP (FM GND)
16
Ω
0.01
µ
F
SRF-M80
7
7
Adjustment Location:
– MAIN BOARD (Component Side) –
AM Tracking Adjustment
RV1
AM IF Adjustment
RV2
FM Stereo Adjustment
L3
FM Tracking Adjustment
L2
AM VCO Voltage Adjustment
CT1
L1
L1
TP
(AM GND)
TP
(FM GND)
TP
(FM ST)
TP
(FM IN)
TP
(+B)
TP
(VT)
– MAIN BOARD (Conductor Side) –
