Read Sony XM-255EX / XM-255NX Service Manual online
XM-255EX/255NX
7
7
SECTION 3
DIAGRAMS
3-1. BLOCK DIAGRAM
DIFFERENTIAL
AMP
Q403
3
1
PRE AMP
IC101(2/2)
LPF
IC201(2/2)
CNJ301(4P)
INPUT
FILTER
(MONO)
HIGH
LEVEL
INPUT
INPUT
L
R
2
CN201
3
1
FILTER
IC301(2/2)
3
1
VR101
VR101(3/4),VR101(4/4)
SW501
FILTER
LPF
OFF
DRIVE AMP
Q404
SWITCH
Q401
DRIVE AMP
Q408
BIAS
Q406,407
POWER AMP
Q410
POWER AMP
Q411
DIFFERENTIAL
AMP
Q402
DRIVE AMP
Q405
DRIVE AMP
Q409
SPEAKER
OUT
L+R MONO
CNJ101
(3/4)
(3/4)
OUTPUT
L
(THROUGH)
CNJ101
(4/4)
(4/4)
LEVEL
VR102
VR102(2/2)
TEST TONE
+B
1
OP AMP
OP AMP
IC401 (1/2)
2
3
7
IC401 (2/2)
5
6
B+
B+
B–
B–
OVER LOAD
DET
Q312
L
R
DIFFERENTIAL
AMP
Q303
5
7
PRE AMP
IC101(1/2)
SW501
LPF
IC201(1/2)
OUTPUT
FILTER
5
7
FILTER
IC301(1/2)
5
7
VR101
VR101(1/4),VR101(2/4)
SW501
FILTER
FILTER
D905
OVER
CURRENT
POWER/PROTECTOR
LPF
OFF
DRIVE AMP
Q304
SWITCH
Q301
DRIVE AMP
Q308
BIAS
Q306,307
POWER AMP
Q310
POWER AMP
Q311
DIFFERENTIAL
AMP
Q302
DRIVE AMP
Q305
DRIVE AMP
Q309
CNJ101
(1/4)
(1/4)
INPUT
R
(THROUGH)
CNJ101
(2/4)
(2/4)
LEVEL
VR102
VR102(1/2)
CN101
REMOTE
PROTECT
LATCH
Q904,905
(20A)
09
F901
DC-DC CONVERTER
CONTROL
IC901
T901
DC-DC CONVERTER
TRANSFORMER
LED
DRIVE
SWITCH
Q909,910
TH901
TH902
+12V
PH901
DC DET
B+
D905
LED
DRIVE
SWITCH
Q911,913
D906
LED
DRIVE
SWITCH
Q914,915
D907
D906
OFFSET
D907
THERMAL
16
1
14
12
ON/OFF
CONTROL
OSC
3
(CURRENT CHECK)
RECT
D908,909
PROTECT
LATCH
Q906,907
OFFSET DET
Q953-954
LINE CONTROL
Q941,942
(CURRENT CHECK)
DRIVER
Q946,949
B+
SWITCH
Q901,902
B+
ON/OFF
DRIVE
Q947
ON/OFF
DRIVE
Q948
+REG
Q944
-REG
Q933
Q933
6
OVER LOAD
DET
Q412
10
9
VCC
Q908
D904
• Signal path
F
: AUDIO
POWER
ON/OFF
Q903
THIS NOTE IS COMMON FOR
PRINTED WIRING BOARDS AND
SCHEMATIC DIAGRAMS.
(In addition to this, the necessary
note is printed in each block.)
PRINTED WIRING BOARDS AND
SCHEMATIC DIAGRAMS.
(In addition to this, the necessary
note is printed in each block.)
For schematic diagrams.
Note:
• All capacitors are in µF unless otherwise
• All capacitors are in µF unless otherwise
noted. pF: µµF 50 WV or less are not in-
dicated except for electrolytics and
tantalums.
dicated except for electrolytics and
tantalums.
• All resistors are in
Ω
and
1
/
4
W or less un-
less otherwise specified.
•
C
: panel designation.
•
U
: B+ Line.
• Power voltage is dc 14.4V and fed with
regulated dc power supply from ACC and
BATT cords.
BATT cords.
• Voltages and waveforms are dc with re-
spect to ground under no-signal condi-
tions.
no mark : POWER ON
tions.
no mark : POWER ON
*
: Impossible to measure
• Voltage are taken with a VOM (Input im-
pedance 10 M
Ω
).
Voltage variations may be noted due to
normal production tolerances.
normal production tolerances.
• Signal path.
F
: AUDIO
For printed wiring boards.
Note:
•
X
: parts extracted from the compo-
nent side.
Click on the first or last page to see other XM-255EX / XM-255NX service manuals if exist.