Yamaha pmn - Manual (Page 120)

E-
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Problem
The sound field parameters and
some other settings on this unit
cannot be changed.
This unit does not operate
properly.
“CHECK SP WIRES” appears on
the front panel display.
The sound is degraded when
listening with headphones
connected to a tape deck or CD
player that is connected to this
unit.
There is noise interference from
digital or high-frequency equip-
ment, or this unit.
This unit suddenly turns into the
standby mode.
Cause
“16 MEMORY GUARD” on the SET MENU is set to
“ON”.
The internal microcomputer has been frozen by an
external electric shock (such as lightning or excessive
static electricity) or by a power supply with low
voltage.
Speaker cables are short circuited.
This unit is in the standby mode.
This unit is too close to the digital or high-frequency
equipment.
The internal temperature becomes too high and the
overheat protection circuitry has been activated.
Remedy
Select “OFF” (see page __).
Disconnect the AC power cord from the outlet and
then plug it in again after about 30 seconds.
Make sure all speaker cables are connected correctly.
Turn on the power of this unit.
Move this unit further away from such equipment.
Wait until this unit cools down and then turn it back
on.
TROUBLESHOOTING
■ Tuner
FM stereo reception is
noisy.
There is distortion, and
clear reception cannot be
obtained even with a good
FM antenna.
The desired station cannot
be tuned in with the
automatic tuning method.
Previously preset stations
can no longer be tuned in.
The desired station cannot
be tuned in with the
automatic tuning method.
There are continuous
crackling and hissing
noises.
There are buzzing and
whining noises (especially
in the evening).
Cause
The characteristics of FM stereo broadcasts may cause
this problem when the transmitter is too far away or
the antenna input is poor.
There is multipath interference.
The station is too weak.
This unit has been disconnected for a long period.
The signal is weak or the antenna connections are
loose.
Noises result from lightning, fluorescent lamps,
motors, thermostats and other electrical equipment.
A TV set is being used nearby.
Remedy
Check the antenna connections.
Try using a high-quality directional FM antenna.
Use the manual tuning method.
Adjust the antenna position to eliminate multipath
interference.
Use the manual tuning method.
Use a high-quality directional FM antenna.
Re-store the stations.
Tighten the AM loop antenna connections and orient it
for best reception.
Use the manual tuning method.
Use an outdoor antenna and a ground wire. This will
help somewhat, but it is difficult to eliminate all noise.
Move this unit away from the TV.
FM
AM
Program