Sony SRF-PSY04 User manual

MICROFILM
SERVICE MANUAL
FM STEREO/AM PLL
SYNTHESIZED RADIO
US Model
SPECIFICATIONS
SRF-PSY04
Photo: Blue model
Ver 1.0 1999. 06

– 2 –
TABLE OF CONTENTS
1. GENERAL ................................................................... 3
2. DISASSEMBLY ......................................................... 4
3. ELECTRICAL ADJUSTMENTS......................... 5
4. DIAGRAMS
4-1. Block Diagram ................................................................ 7
4-2. Printed Wiring Boards..................................................... 9
4-3. Schematic Diagram ......................................................... 11
4-4. IC Pin Function Description ........................................... 15
5. EXPLODED VIEW................................................... 16
6. ELECTRICAL PARTS LIST ............................... 17
Notes on chip component replacement
• Never reuse a disconnected chip component.
• Notice that the minus side of a tantalum capacitor may be dam-
aged by heat.
CF
3
CF1
mark
Mark Center frequency
red 10.70 MHz
blue 10.67 MHz
orange 10.73 MHz
black 10.64 MHz
white 10.76 MHz
HOW TO CHANGED THE CERAMIC FILTERS
This model is used two ceramic filters of CF1 and CF3.
You must use same type of color marked ceramic filters in order to
meet same specifications.
Therefore, the ceramic filter must be changed two pieces together
since it’s supply two pieces in one package as a spare parts.

– 3 –
SECTION 1
GENERAL This section is extracted from
instruction manual.

– 4 –
FRONT CABINET
MAIN BOARD, KEY BOARD
SECTION 2
DISASSEMBLY
Note: Follow the disassembly procedure in the numerical order given.
4 front cabinet
3 two claws
1 lid, battery case
2 two screws
(P2
× 8)
3 two claws
1 two claws
2 KEY board
2 MAIN board

– 5 –
SECTION 3
ELECTRICAL ADJUSTMENTS
AM IF ADJUSTMENT
Adjust for a maximum reading on level meter
T1 450 kHz
AM FREQUENCY COVERAGE ADJUSTMENT
Adjustment Part Frequency Display Reading on Digital Voltmeter
L5 530 kHz 2.7 ± 0.1V
Confirmation 1,710 kHz 8.9 ± 1V
AM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter
L2 580 kHz
CT1 1,490 kHz
FM VCO VOLTAGE CONFIRMATION
Frequency Display Reading on Digital Voltmeter
87.5 MHz 2.7 ± 0.1V
108 MHz 8.9 ± 1V
FM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter
L3 87.5 MHz
CT2 108 MHz
0 dB=1 µV
[AM]
Setting:
BAND switch: AM
[FM]
Setting:
BAND switch: FM
FM SENS switch: DX
• Repeat the procedures in each adjustment several times, and the
tracking adjustments should be finally done by the trimmer ca-
pacitors.
Adjustment Location: Main Board (See page 6)
FM RF signal
generator
22.5 kHz frequency
deviation by 400 Hz
signal
Output level: as low as possible
+
–
level meter
2 (headphones) jack (J1)
set
MAIN board
TP (ANT) 16
Ω
0.01 µ F
+
–
digital voltmete
r
MAIN board
TP (VT)
FM STEREO (76 kHz) Adjustment
Setting:
BAND switch: FM
FM SENS switch: DX
Procedure:
1. Connect the frequency counter to TP (76 kHz) as shown the
figure below.
2. Tune the set to 98 MHz.
3. Adjust RV1 for 76 kHz reading on the frequency counter.
Specification: 75.5 to 76.5 kHz
Adjustment Location: MAIN board (See page 6)
0.01 µ F
MAIN boar
d
TP (ANT)
set
FM RF signal
generator
Carrier frequency : 98 MHz
Modulation : 1 kHz, 22.5 kHz deviation
Output level : 562
µ
V
(
55 dB
)
+
–
MAIN board
TP (76 kHz)
+
1 µ F
frequency
counter
AM RF signal
generator
30% amplitude
modulation by
400 Hz signal
Output level: as low as possible
Put the lead-wire
antenna close to
the set.
+
–
level meter
set
16 Ω
2
(headphones) jack (J1)

– 6 –
– MAIN BOARD (Component Side) –
Adjustment Location:
– MAIN BOARD (Conductor Side) –
IC2
IC1
J1
RV1
FM Stereo (76 kHz)
Adjustment
L5
AM Frequency Coverage
Adjustment
CT2
L3 FM Tracking
Adjustment
T1
AM IF Adjustment
L2
CT1
AM Tracking Adjustment
L1
L4
IC1
TP (76 kHz) TP (ANT) TP (VT)

SRF-PSY04
– 7 – – 8 –
SECTION 4
DIAGRAMS
4-1. BLOCK DIAGRAM
18
20
16 13
19
24 22
FM
FRONT-END
FM IF AMP/
DISCRI
DECODER
AMP
SWITCH
POWER
AMP
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
10.7MHz
CF1
10.7MHz
SYSTEM CONTROLLER,
LIQUID CRYSTAL DISPLAY DRIVER,
KEY CONTROL
IC101
CF2
450kHz
FM
RF
26
FM DISCRI
FM
IF IN
6
721
5
L-CH
OUT
R-CH
OUT
4
27
29
123
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
RV1
FM STEREO
(76kHz)
L5
AM FREQUENCY
COVERAGE
CT2, L3
FM TRACKING
S1
FM SENS
T1
AM IF
CT1, L2
AM TRACKING
L.P.F.
B.P.F.
FM VCO
BUFFER
Q1
FM/AM BAND
SELECT SWITCH
Q2
LIQUID CRYSTAL DISPLAY
LCD101
VOLTAGE
DETECT
IC102
B+ SWITCH
Q103, 104
DC/DC
CONVERTER
Q106, 107, T101
LOW-PASS
FILTER
Q101, 102
• SIGNAL PATH
: FM
: AM
05
POWER
AMP
MUTE
CONTROL
KEY MATRIX
S101 – 111
PC0 – PC3 PB0 – PB2
X1
75kHz
SYSTEM CONTROLLER (IC101) B+
FM/AM TUNER (IC1),
HEADPHONE AMP (IC2) B+
PLL LOW-PASS FILTER CIRCUIT B+
D102
–1
–2
HEADPHONE AMP
IC2
2
4
IN1
IN2
9
7
OUT1
OUT2
B+
VREF
CT1
D1-1
L2
AM FERRITE-ROD
ANTENNA
L3
FM RF
POWER XOUT XIN CE
MT/SW
REG
VCC
EO
VCOL
VCOH
BAND
12 13 9 11
10
MUTE
10
BEEP
6
7
181916
DX
LOCAL
D1-2 D3
CT2
D2
L5
AM OSC
L4
FM OSC
RV2
VOL
J1
(HEADPHONE)
2
DRY BATTERY
SIZE “AAA”
(IEC DESIGNATION R03)
2PCS. 3V
37, 38, 12 – 5
COM0 – COM3
32 – 29
LCD0 – LCD8
28 – 20
+
+

SRF-PSY04
– 11 – – 12 –
Note on Schematic Diagram:
• 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 Ωand 1/4W or less unless otherwise
specified.
•¢: internal component.
•C: panel designation.
•U: B+ Line.
•H: adjustment for repair.
• Power voltage is dc 3V and fed with regulated dc power
supply from battery terminal.
• Voltages and waveforms are dc with respect to ground
under no-signal (detuned) conditions.
4-3. SCHEMATIC DIAGRAM • See page 13 forWaveforms. •See page 14 for IC Block Diagrams.
no mark : FM
( ) : AM
〈〈 〉〉 : POWER OFF
• Voltages are taken with aVOM (Input impedance 10 MΩ).
Voltage variations may be noted due to normal production toler-
ances.
• Waveforms are taken with a oscilloscope.
Voltage variations may be noted due to normal production toler-
ances.
• Circled numbers refer to waveforms.
• Signal path.
F: FM
f: AM

– 13 – – 14 –
• Waveforms
– KEY Board –
1IC101 !™ XOUT
500 mV/DIV, 10 µs/DIV
2IC101 !£ XIN
500 mV/DIV, 10 µs/DIV
3T101
10 V/DIV, 200 ns/DIV
4Q106 Collector
2 V/DIV, 200 ns/DIV
5Q106 Base, Q107 Collector
200 mV/DIV, 200 ns/DIV
1.2 Vp-p
13.3 µ s
2 Vp-p
13.3 µ s
34 Vp-p
424 ns
5.2 Vp-p
320 ns
616 mVp-p
320 ns
• IC Block Diagrams
– MAIN Board –
IC1 CXA1238M-T6
VCO
REGULATOR
FM FRONT-END
AM FRONT-END
MPX
REGULATOR
MONO/STEREO
SELECT
DECORD
AMP
MUTING
AUTO
BLEND
TUNING
INDICATOR
AM IF/
DET
FM IF/
DISCRI
RIPPLE
FILTER
BAND-PASS
MUTE
1
27
28
2930 242526 212223 181920 1617
2 3 4 5 6 7 8 9
PLL LPF1
PILOT DET LPF2 PILOT DET LPF2
ST IND/VCO CHECK
L-CH OUT
VCC
R-CH OUT
RIPPLE FILTER
AGC AFC1
10
AGC AFC2
13
FM IF IN
14
AM IF IN
15
BAND SELECT
11
GND
12
TUNE IND
1/2
COUNTER
1/2
COUNTER
PD1
PD2
FM/AM FE OUT FM GND
FM RF IN AM RF IN FM RF REG FM OSC AFC AM OSC MUTE FM DISCRI GND PLL LPF2 MPX REG VCO
IC2 LA4533M
MT/SW
OUT1
POWER GND
OUT2
VCC
P/SW
IN1
PRE GND
IN2
REF
1
2
3
4
5
10
9
8
7
6
POWER
AMP
POWER
AMP
MUTE
CONTROL
POWER
SWITCH
BIAS