Sony STR-W55 User manual

MICROFILM
SERVICE MANUAL
STR-W55 is RECEIVER section in
MHC-W55.
AEP Model
UK Model
STR-W55
FM STEREO/FM-AM RECEIVER

– 2 –
Specifications ...................................................................................1
1. GENERAL ...............................................................................3
2. TEST MODE ...........................................................................4
3. ELECTRICAL ADJUSTMENTS ..........................................5
4. EXPLANATION OF ICTERMINALS ..................................6
5. DIAGRAMS
5-1. Printed Wiring Boards – Main Section–..........................10
5-2. Schematic Diagram – Main Section–..............................13
5-3. Schematic Diagram – Panel Section– .............................18
5-4. Printed Wiring Boards – Panel Section– .........................21
5-5. Schematic Diagram – TCB Section–...............................23
5-6. Printed Wiring Boards – TCB Section– ..........................25
6. EXPLODED VIEWS
6-1. Chassis Section................................................................26
6-2. Front Panel Section .........................................................27
7. ELECTRICAL PARTS LIST ...............................................28
Section Title Page
TABLE OF CONTENTS
MODEL INDENTIFICATION
– BACK PANEL –
Parts No. Model
4-978-033-6πUK
4-978-033-2πAEP, German, Italian, AED
rAbbreviation
AED : Norway, Sweden, Finland, Denmark
Notes on chip component replacement
• Never reuse a disconnected chip component.
• Notice that the minus side of a tantalum capacitor may be damaged
by heat.
SAFETY-RELATED COMPONENT WARNING!!
COMPONENTS IDENTIFIED BY MARK !OR DOTTED LINEWITH
MARK !ONTHE SCHEMATIC DIAGRAMS AND INTHE PARTS LIST
ARE CRITICALTO SAFE OPERATION.
REPLACETHESECOMPONENTSWITH SONY PARTSWHOSEPART
NUMBERS APPEAR AS SHOWN IN THIS MANUAL OR IN
SUPPLEMENTS PUBLISHED BY SONY.
220-230V AC, 50/60Hz (EXCEPT UK)
220-240V AC, 50/60Hz (UK)

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SECTION 1
GENERAL This section is extracted from
instruction manual.

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SECTION 2
TEST MODE
DISPLAY / KEYTEST MODE
Press the ENTER/NEXT and FUNCTION buttons simultaneously.
Then press the MENU 1 button with the following 4 seconds to set the Test Mode.
1. The message “W1 J (destination) ” appears on the screen and a 32 cycle square wave of the subcrystal oscillator is output from Pin 24
(AUB. OUT).
2. Press any key to rotate JOG and all FL indicators light up.
When you rotate JOG at this point, the display changes as follows.
Nall FL indicators on Nn FL pattern 1 Nn FL pattern 2 n
The changes and all LED indicators light up.
3. Again press any key to set the key count check. The following display appears.
00 0
The numbers in order from left to right show ; the number of keys pressed, the JOG count (1 click per 4 counts), and the VOL count.
(1 cycle is a count of 96.)
4. Press the Power button to reset to the factory settings.
AMPTEST MODE
Press the ENTER/NEXT and FUNCTION buttons simultaneously.
Then press the MENU 2 button with the following 4 seconds to set the Test Mode.
1. The message “AMP TEST” appears on the screen. Press the MENU button to call up the Equalizer Curve for theAmp Test.
However when the function is set to the tuner, use the MENU button to call up each tuner preset from 1 through 5.
2. Press the Power button to reset to the factory settings.
MICROCOMPUTER COLD START
Press the ENTER/NEXT and FUNCTION buttons simultaneously.
Then press the MENU 3 button with the following 4 seconds to reset the microcomputer to the factory settings.
SUBCRYSTALTEST MODE
Press the ENTER/NEXT and FUNCTION buttons simultaneously.
Then press the MENU 4 button with the following 4 seconds.
The message “XTAL TEST ” appears on the screen and a 32 cycle square wave of the subcrystal oscillator is output from Pin 24 (AUB.OUT).
In addition, a square wave of the same frequency as the subcrystal oscillator, is output from 4PIN (POWER. ON/OFF).
Press the Power button to reset to the factory settings.

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SECTION 3
ELECTRICAL ADJUSTMENTS
Precautions in Repairing
Note. 1 : The adjustment should be performed in the publication.
(AM nFM)
Note. 2 : As a front-end (FE1) is difficult to repair if faulty, replace it
with new one.
AM SECTION
AMTuned Indication Lighting Level
Setting :
Band :AM ( MW)
set
AM RF signal
generator
Carrier frequency : 999kHz
loop antenna B
loop antenna A
Procedure :
1. Set loop antennaA so that the loop antenna B input level becomes
55dBµ/m (0.6mV/m).
2. Tune the set to 999kHz .
3. Adjust RV41 so that the TUNED indicator goes on.
FM SECTION
FMTuned Indication Lighting Level
Note : Always make the tuning level adjustment first.
(Since it affects the FM tuning level.)
Setting :
Band : FM
set
FM RF stereo signal
generator FM ANTENNA terminal
Carrier frequency : 98MHz
Modulation : OFF
Output level :0.018mV (25dB µ )
75 Ω coaxial
Procedure :
1. Tune the set to 98MHz.
2. Adjust RV42 so that the TUNED indicator goes on.
Adjustment Location : TCB board
Adjustment Location :
[TCB BOARD ] – Component side –
RV42 : FM Tuned Indication Lighting Level
RV41 : AMTuned Indication Lighting Level
FE1

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1VDD – Power supply.
2 CLK OUT O Direct output for communications with HCD-W55.
3 RDY IN I/O Direct input / output for communications with HCD-W55.
4 POWER ON / OFF O L : Relay ON
5 MUTE O Mute output to transistor. L : Mute ON
6,7 – – Not used.
8 427LAT O Latch output to IC105 (M62427FP).
9 LED LAT O Latch output to IC504 (M66313FP).
10 RESET I Reset terminal.
11 X2 – Oscillator connection terminal. (5MHz)
12 X1 – Oscillator connection terminal. (5MHz)
13 IC – Ground connection.
14 XT2 – Oscillator connection terminal. (32MHz)
15 XT1 – Oscillator connection terminal. (32MHz)
16 VDD – Power supply.
17 BACK UP I AC Power supply OFF.
18 COM CLK O Transfer clock output serial data.
19 COM DATA O Serial data output.
20 ST DATA IN I Serial data input from IC 1.
21 ST CE O Chip enable output to IC 1.
22 STEREO I Stereo signal input.
23 TUNED I Tuned signal input.
24 AUB OUT O Audio bus output.
25 AVSS – Ground.
26 – – Not used.
27 SUFFIX I Input for model select.
28 SPE I Spectrum analyzer signal input.
29 SPE I Spectrum analyzer signal input.
30 SPE I Spectrum analyzer signal input.
31 SPE I Spectrum analyzer signal input.
32 KYE 1 I Key data input (A/D converter).
33 KYE 2 I Key data input (A/D converter).
34 AVDD – Power supply for anlog.
35 AV REF – Reference voltage forA/D converter.
36 VOL IN A I Volume encoder input.
37 JOG IN A I JOG dial encoder input.
38 RDS CLK I Not uset.
39 AUB IN I Audio bus output.
40 VSS – Ground.
IC501 1 ASD0204GF-011-3BA (SYSTEM CONTOROL)
SECTION 4
EXPLANATION OF ICTERMINALS
Pin No. Pin name I/O Description

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41 RDS DATA I Not uset.
42 D 3 I/O System control data signal input / output.
43 D 2 I/O System control data signal input / output.
44 D 1 I/O System control data signal input / output.
45 D 0 I/O System control data signal input / output.
46 VDD – Power supply +5V.
47 SIRCS IN I SIRCS signal input.
48 VOL IN B I Volume encoder input.
49 JOG IN B I JOG dial encoder input.
50 ST FM O BAND select output.
51 ST MUTE O
52 EMG OUT O Urgent signal standby output. “H” : standby
53 EMG IN I Urgent signal start input. “H” n“L” : start
57 – 78 P 32 – P 8 O Segment output to FL501.
79 VG – Power supply for fluorescent indicator tube.
80 – 86 P 7 – P 1 O Segment output to FL501.
87 – 100 14 G – 1 G O Grid output for FL501.
FM Receiving AM Receiving MUTE
%º pin H L H
%¡ pin L L H
Pin No. Pin name I/O Description

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