Yamaha NX-U10 - Speaker Sys, Service Manual

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NX-U10
8
NX-U10
■
TROUBLESHOOTING
• When the status indicator LED does not light up when "POWER" key is pressed.
• When no sound is produced.
NG NG
OK OK
PC/Macintosh and the main unit
are connected
with the USB cable.
Install
the USB/AC adapter
to the USB cable and connect it
to the AC outlet.
Does the LED turn
on ?
Disconnect
the USB cable from
the main unit and load the battery.
Does the LED turn
on ?
• Remove the USB/AC adapter,
connect the USB cable again and re-
check.
• Check USB DAC (IC2) and
peripheral circuit.
• Connect the cable to another PC/
Macintosh and check.
• Check the power circuit (IC1 and
Q15) and peripheral circuit.
(Is the power v5V and +12V
correct ?)
• Check the power circuit (IC15 and
IC16) and peripheral circuit.
(Is the power v5V, +12V and
+50V correct ?).
NG
OK
NG
OK
NG
OK OK
NG
PC/Macintosh and the main unit
are connected
with the USB cable.
Is the USB cable
connected properly?
• Recheck after reconnecting
the USB cable or after replacing
it with a new one.
Is
the audio device
of PC/Macintosh set to
“USB AUDIO DAC”? Also, is the
volume setting
muted ?
• Recheck settings on the PC/
Macintosh side.
Connect
the main unit and
PC/Macintosh or the
portable audio player to the
PORTABLE terminal with
3.5mm mini-plug cable.
Is the sound
produced ?
Is the power voltage (+5V and +12V)
correct ?
• Check the power circuit (IC1, IC15,
IC16, Q15) and peripheral circuit.
• Check USB DAC (IC2) and
peripheral circuit. • Check the audio circuit (IC5, IC9,
IC10 and IC12) and peripheral circuit.