Marantz PM7001 Stereo Amplifier User Manual


 
14
ENGLISH
TROUBLESHOOTING
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7 Before considering it as a failure
In case of trouble with this component, first check the following
before calling for service.
What seems to be a serious malfunction is often due to a simple
operation mistake.
If the trouble is not fixed after making the following checks,
contact the place of purchase, your nearest Marantz dealer,
our customer service center, or our repair service center.
* Power does not turn ON.
1. Is the power cable plugged securely into the power outlet?
2. Isn’t the STANDBY indicator above the POWER ON/OFF
button lit? Either turn the INPUT SELECTOR knob, or press
the MAIN POWER ON button on the remote controller.
3. If the STANDBY indicator is flashing, the protective circuit
has been activated. Switch the PM7001’s POWER ON/OFF
button to the OFF position, wait for more than a minute,
and then turn the power back ON.
* Nothing is heard from the speakers.
1. Aren’t the SPEAKER 1 and 2 buttons on the front panel in
the OFF position?
2. Isn’t the MUTE function activated?
3. Did you make a mistake selecting the input source using
the INPUT SELECTOR knob on the front panel?
4. Are you using the component correctly?
5. Are connection cables and speaker cables securely
connected.
6. Is the SEPARATE switch on the rear panel set correctly?
7. The volume may have been muted by the protective circuit
activated. Try adjusting the volume level again.
* Record player audio is not heard, or
contains a lot of noise.
1. Are the PHONO plugs connected correctly?
2. Connect the grounding wire from the record player to the
PHONO GND terminal.
3. Is the cartridge connected properly to the tone arm?
4. Sometimes plugging the record player’s power cable into
the power outlet with the polarity reversed can reduce noise.
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7 About the Protective Circuit
The PM7001 is equipped with a protective circuit to protect
the amplifier circuits and speaker system against damage.
If the protective circuit is activated, the sound is instantly muted.
In this case, either the MUTE indicator in the center of the
panel flashes, or the STANDBY indicator above the POWER
ON/OFF button flashes.
At Power On
For about 8 seconds after the power is turned on, the protective
circuit is activated muting the sound to give the amplifier circuits
time to stabilize. Once the amplifier circuits stabilize, the
protective circuit releases and audio is enabled.
In the Event of Overcurrent
The protective circuit is activated if current exceeding a certain
level is detected, which can happen if excessive signal flow is
input to the amplifier or if the PM7001 is connected to a speaker
system of less than 4 impedance. The protective circuit is
also activated if a speaker cable shorts.
In these cases, the MUTE indicator in the center of the panel
flashes, and the volume is automatically reduced. Approximately
15 seconds later the protective circuit is released, therefore
the volume needs readjusting to continue normal use.
Moreover, if the overcurrent continues, the amplifier’s power
shuts OFF and the STANDBY indicator above the POWER
ON/OFF button flashes.
If excessive ultra-bass signals are input
The protective circuit is also activated if ultra-bass signals that
exceed the base signal range settings are input.. In this case,
the MUTE indicator in the center of the panel flashes, and the
volume is automatically reduced. Approximately 15 seconds
later, the protective circuit is released, therefore the volume
needs readjusting to continue normal use. If excessive ultra-
bass signal input continues or if DC voltage is detected due to
trouble with the amplifier, the power shuts OFF and the
STANDBY indicator above the POWER ON/OFF button flashes.
If the Main-amplifier Overheats
The protective circuit is activated if the temperature of the main-
amplifier section rises above a certain level, which can happen
if the amplifier is continually used with excessive signal flow
being input into it. The protective circuit is also activated when
the set operating temperature is exceeded, which can happen
if the vents on top of the amplifier are covered, or if the amplifier
is installed on a cramped audio rack. In these cases, the MUTE
indicator in the center of the panel flashes, and the volume is
automatically reduced. Approximately 15 seconds later, the
protective circuit is released, therefore the volume needs
readjusting to continue normal use.
If the temperature does not sufficiently lower within a certain
amount of time after the protective circuit activation, the power
shuts OFF and the STANDBY indicator above the POWER
ON/OFF button flashes.
In the Event of Amplifier Trouble
The protective circuit is activated and the power is automatically
shut OFF if an abnormality is detected in the power circuit.
The same happens if the main fuse inside the amplifier blows.
In these cases, the STANDBY indicator above the POWER
ON/OFF button flashes.