Read Sony SRF-R405 Service Manual online
SRF-R405
Tourist Model
SERVICE MANUAL
FM STEREO/AM PLL SYNTHESIZED RADIO
SPECIFICATIONS
Frequency range
Band
Band
Frequency range
Channel step
FM
76 – 108 MHz
0.1 MHz
AM
530 – 1,710 kHz
9 kHz/10 kHz
Speaker
Approx.2.8 cm (1
1
/
8
inches) dia., 7.2
Ω
Output
2 (headphone) jack
(
(
∅
3.5 mm, stereominijack)
Power output
80 mW (at 10% harmonic distortion)
Power requirements
3 V, DC two R03 (size AAA) batteries
Power Auto Off function
Approx.30 minutes, 60 minutes,
90 minutes,120 minutes, and off
90 minutes,120 minutes, and off
Dimensions Approx. 55
×
98
×
17 mm(w/h/d)
(2
1
/
4
×
3
7
/
8
×
11
/
16
inches) not incl.
projecting parts and controls
Approx. 59.2
Approx. 59.2
×
98.2
×
17.8 mm(w/h/d)
(2
3
/
8
×
3
7
/
8
×
23
/
32
inches) incl.
projecting parts and controls
Mass
Approx. 89 g (3.1 oz) incl. batteries
Accessories Batteries (2)
Carrying case (1)
Design and specifications are subject to change
without notice.
without notice.
Sony Corporation
Personal Audio Group
Published by Sony Engineering Corporation
Published by Sony Engineering Corporation
9-927-115-12
2005G16-1
© 2005.07
© 2005.07
Ver. 1.1 2005.07
— 2 —
Notes on chip component replacement
• Never reuse a disconnected chip component.
• Notice that the minus side of a tantalum capacitor may be damaged
• Notice that the minus side of a tantalum capacitor may be damaged
by heat.
SECTION 1
GENERAL
This section is extracted
from instruction manual.
from instruction manual.
— 3 —
SECTION 2
DISASSEMBLY
2-1. CABINET (REAR) ASSY
Note :
Follow the disassembly procedure in the numerical order given.
Note :
On installation of cabinet (rear), adjust the knob (earphone/speaker) and switch positions until they agree.
1
Open the lid, battery case
7
Cabinet (rear) assy
6
Open the cabinet from
the recessed areas.
(Remove the 9 claws.)
(Remove the 9 claws.)
Claws
Claws
Claws
Knob (EAR/SP)
Switch
Claws
3
Open the lid, ear-phone
2
Screw (M1.7
×
5)
4
Screw (M1.7
×
5)
5
Screw (M1.4
×
10)
2-2. MAIN BOARD
Note :
On installation of cabinet (rear), adjust the knob (earphone/speaker) and switch positions until they agree.
4
Screw (B1.4
×
6)
5
Claw
Switch
1
Knob(HOLD)
7
Button(NOISE CUT)
8
Spring compression
6
Main board
2
Remove two solders
of terminal, battery.
3
Remove two solders
of speaker leads.
— 4 —
SECTION 3
ELECTRICAL ADJUSTMENTS
[FM]
Setting
ENT/BAND switch : FM
Signal generator
ENT/BAND switch : FM
Signal generator
[AM]
Setting
ENT/BAND switch : AM
ENT/BAND switch : AM
FM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter.
L202
76.0MHz
CT202
108.0MHz
TUNER SECTION
AM VCO ADJUSTMENT
Adjust so that the voltage at TP3(LPF) becomes 2.60 ±0.05V.
L205
531kHz
AM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter.
L201
585kHz
CT201
1,485kHz
0 dB = 1 µV
• Repeat the procedures in each adjustment several times for a
maximum reading on level meter, and the frequency coverage
and tracking adjustments should be finally done by the trimmer
capacitors.
and tracking adjustments should be finally done by the trimmer
capacitors.
Adjustment Location :
– MAIN board (side A) –
– MAIN board (side B) –
TP3 (LPF) TP1 (ANT)
TP4
(76kHz)
L202, CT202
FM Tracking Adjustment
FM Tracking Adjustment
L201, CT201
AM Tracking Adjustment
AM Tracking Adjustment
RV301
FM STEREO (76kHz)
Adjustment
FM STEREO (76kHz)
Adjustment
L205
AM VCO Adjustment
AM VCO Adjustment
T201
AM IF
Adjustment
AM IF
Adjustment
22.5 kHz frequency
deviation by
400 Hz signal 30%
Output level : as low as possible
deviation by
400 Hz signal 30%
Output level : as low as possible
FM RF signal
generator
generator
Set
0.01
µ
F
TP1(ANT)
Level meter
Headphones jack
(J401)
(J401)
MAIN board
16
Ω
AM RF signal
generator
generator
Put the lead-wire
antenna close
to the set.
antenna close
to the set.
Set
Headphones jack
(J401)
(J401)
MAIN board
TP3(LPF)
TP3(LPF)
Digital
Volt meter
Volt meter
Level meter
16
Ω
30% amplitude
modulation by
400 Hz signal
Output level : as low as possible
modulation by
400 Hz signal
Output level : as low as possible
AM IF ADJUSTMENT
Adjust for a maximum reading on level meter.
T201
450kHz
FM STEREO (76kHz) ADJUSTMENT
Adjustment point
Frequency Indication
Frequency counter Reading
RV301
FM76MHz
76kHz ±200Hz
FM STEREO (76kHz)
Procedure :
1. Connect frequency counter to the positions shown below.
2. Tune the set to 76MHz.
2. Tune the set to 76MHz.
0.01
µ
F
FM RF SSG
to TP1(ANT)
Carrier frequency : 76MHz
Modulation : no modulation
Output level : 0.1V (100dB)
Modulation : no modulation
Output level : 0.1V (100dB)
Frequency counter
0.01
µ
F
+
–
–
TP4(76kHz)
Use a frequency counter
having input impedance
of 10M
having input impedance
of 10M
Ω
or higher.
