AUSTRALIAN MONITOR AM1600, Руководство по эксплуатации

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Front Panel
Figure 1 shows the panel layout of the
AM1600
. The
functions of the controls and indicators are as follows:
1. Attenuator
Level control for your amplifier is provided by a 21
position detented potentiometer and indicates gain
reduction in decibels from the 0 dB position
(maximum gain, no attenuation).
2. VU Meter - Status Indicator
Level Indication
(see insert - 1)
Each channel features a variable 10 segment display
showing the actual power/volume level available
before clipping (taking mains supply and load duty
into account).
The display is colour coded, and calibrated in 3dB
increments.
The 10 LEDs are:
Green = -27dB to -21dB
Yellow = -18dB to -6dB
Red = -3dB and the two LEDs indicating
the clipping point.
Power On Indication
Two Green LEDs either side of the mains switch
(above the "ON" legend) are used to indicate that
the unit is on. The first Green LED indicates the 15
Volt preamp supply is present (the left hand side
display shows -15V, and the right hand side shows
the +15V).
The next LED outwards is also a supply indicator
and shows that the Positive High Current Output
Rail is available to the corresponding channel.
NOTE: The amplifier is not damaged by running into
clipping, but speakers may be. To maximise the life
of your speakers, try to keep clipping infrequent.
3. Power Switch
Press the switch DOWN for power ON and UP for
power OFF. At start-up (turn-on) the input to the
amplifier is muted by 30dB for approximately two
seconds.
4. Thermal Indicator
When switching the amplifier on, this red LED will
flash momentarily, indicating correct operation of
the Mains In-Rush Current Suppression circuit.
After establishment of Inrush Current Suppression
circuit the LED will extinguish. This LED will not
illuminate during normal use of the amplifier.
In the advent of a thermal overload this LED will
illuminate red indicating that the internal operating
temperature of one or both amplifier channels has
exceeded a safe level of operation and the amplifier
will be shut down. The fans will continue to run and
once the amplifier has cooled down sufficiently, the
amplifier will start up automatically providing Inrush
Current Suppression and input signal muting until
establishment of the amplifier after which it will
return to normal operating mode.
NOTE: You should always ensure that the fan grille
is kept clean and free from the build up of dust and
lint. This will ensure longer operation of your amplifier
and reduce the possibility of it prematurely going
into thermal shutdown mode.
5. Fault Indicator
This amber LED will illuminate when a fault condition
exists.
The fault detection circuit monitors the difference
between drive and output in your amplifier.
If you have a short on the speaker output (or a blown
negative rail fuse) the LED will flash brightly in sync
with the programme. This LED will also flash with
programme peaks for gross overloads or if the load
is 2 ohms or less.
The circuit has two stages of operation:
1. It will provide indication (e.g. gross overload) but
does not affect the input signal (a faint flash).
2. It will indicate and mute the input signal (e.g.
shorted output) (brightly flashing or permanently
on).
In the advent of a failure the display panel reverts to
a fault display to assist in diagnosis of the fault.
- The VU meter will light up fully and the Positive
Output Rail LED will extinguish if the positive
supply rail is not available (check rear +ve rail fuse).
- The fault Led will glow brightly if the Negative
Output Rail is not available (check rear -ve rail fuse).
- Failure of the pre-amp supply will cause the
amplifier to be muted and indicator LEDs to be
extinguished.
Controls & Connectors 7