AUSTRALIAN MONITOR AM1200 Specifications download pdf (Page 7)

Front Panel

Figure 1 shows the panel layout of the AM1200. 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. Status Indicator

This is a dual colour LED which displays the status

of the output stage and displays three levels of

operation.

These levels are:

Below -20dB (unlit)

-20dB and above (green)

1dB below actual clipping (red)

The LED will turn green once the output voltage

exceeds the -20dB point (3.5 volts).

The LED will change to red once the output ex-

ceeds the -1dB point before actual clipping of the

amplifier’s output stage. The threshold of the -1dB

point is referred to the amplifier supply rails and

alters with changes in the mains supply, changes

in the load and duty cycle fluctuations.

The attack and decay time (ballistics), of the status

circuit are those of a Peak Programme Meter

(P.P.M.)

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. 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).

4. 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.

5. On / Thermal Indicator

When switching the amplifier on, this red LED will

momentarily flash Red, indicating correct operation

of the Mains In-Rush Current Suppression circuit.

After establishment of the Inrush Current

Suppression circuit the LED will change to Green

indicating the unit is on and receiving mains power.

In the advent of a thermal overload this LED will

illuminate red indicating that the internal operating

temperature of one or all 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.

6. Bridge Mode Indicator

This LED will illuminate yellow when the relative

pairs of channels of the amplifier have been selected

to operate in a "BRIDGE" mode of operation.

Selection of the bridge mode is accomplished by

engaging the rear panel "PUSH TO BRIDGE" Switch.

See section 5 (page 15) for more information on

Bridge mode operation.

Controls & Connectors 7

1 2 3 4 5 6 7 8 9 10 11 12 ... 19 20

Comments to this Manuals

No comments

AUSTRALIAN MONITOR AM1200 Specifications Page 7

Comments to this Manuals

Related products and manuals for Audio amplifiers AUSTRALIAN MONITOR AM1200