Test Mode; Diagrams; Circuit Boards Location - Sony STR-SE381 Service Manual

INITIALIZATION MODE
* All preset contents are cleared when this mode is activated. Use
this mode before returning the product to clients upon
completion of repair.
* Procedure:
While depressing the VIDEO, TAPE/MD and the CD buttons
simultaneously, press the power [I/u] button to turn on the main
power. The message INITIAL appears and initialization is
performed.
FLUORESCENT INDICATOR TUBE TEST MODE
* All fluorescent segments are tested. When this test is activated,
all segments turn on at the same time, then each segment turns
on one after another.
* Procedure:
While depressing the CD and the TAPE/MD buttons
simultaneously, press the power [I/u] button to turn on the main
power. All segments turn on at the same time, then each segment
turns on one after another. The message FINISH appears when
this test is complete.
SECTION 2

TEST MODE

AM CHANNEL STEP 9 kHz/10 kHz
SELECTION MODE
* Either the 9 kHz step or 10 kHz step can be selected for the AM
channel step.
* Procedure:
Set the FUNCTION to AM. Turn off the main power.
While depressing the TUNING+ button, press the power [I/u]
button to turn on the main power. Either the message 9k STEP
or 10k STEP appears. Select the desired step.
REAR SPEAKER GAIN UP MODE
* The rear speaker gain can be set to either NORMAL or GAIN
UP.
* Procedure:
While depressing the -SURROUND button, press the power [I/
u] button to turn on the main power. Either the message
NORMAL or GAIN UP appears. When the product enters this
mode again, the other gain appears. Select the desired gain.
— 5 —
3-1.

CIRCUIT BOARDS LOCATION

PRIMARY board
SW board
DISPLAY board
SW (A) board
SW (B) board
KEY
THIS NOTE IS COMMON FOR PRINTED WIRING
BOARDS AND SCHEMATIC DIAGRAMS.
(In addition to this necessary note is printed in each
block.)
For schematic diagrams.
Note:
• 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 Ω and
1 / W or less unless otherwise
4
specified.
• % : indicates tolerance.
• : internal component.
¢
• 2 : nonflammable resistor.
• 1 : fusible resistor.
• C : panel designation.
Note:
The components identified by
mark ! or dotted line with mark
! are critical for safety.
Replace only with part number
specified.
• U : B+ Line.
• V : B– Line.
• H : adjustment for repair.
• Voltages and waveforms are dc with respect to ground
under no-signal (detuned) conditions.
No mark : FM
• Voltages are taken with a VOM (Input impedance 10 MΩ).
Voltage variations may be noted due to normal production
tolerances.
• Waveforms are taken with a oscilloscope.
• Circled numbers refer to waveforms.
• Signal path.
F
: FM
SECTION 3

DIAGRAMS

SECONDARY board
STANDBY board
MAIN board
VOLUME board
board
VR-TONE board
For printed wiring boards.
Note:
• X : parts extracted from the component side.
• b : Pattern from the side which enables seeing.
• Waveforms
— 6 —
STR-SE381