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Redback® Proudly Made In Australia
4
Redback® A 4270/80
Four Zone Paging PA Amplifier
3.0 FRONT PANEL CONTROLS
Figure 1 shows the layout of the front panel.
Fig 1
1
Inputs 1-4 volume controls
Use these controls to adjust the output volume of inputs 1-4 (volume 3 is used to adjust the volume of input 4 the
music input.
2
Master volume Control
Use this control to adjust the master volume.
3
Protect Indicator
This LED indicates when the amplifier module has an internal circuitry fault.
4
BGM Output Select Switches
Use these switches to select which zones are to receive the background music.
5
Status Indicators
Normal Mode: Indicates that the amplifier is operating in normal mode (i.e. no paging or Evac tones active).
Mic Paging Active: Indicates when an A 4488 paging mic console is in use.
Mic BGM Active: Indicates when the BGM input on the rear of an A 4488 paging console is active.
Evac Tones Active: Indicates when the Alert or Evac tones are active.
6
Power Switch
Use this to turn the unit on.
7
On Indicator
This led indicates the unit has power.
8
24V DC Indicator
This LED indicates when the amplifier is being powered from the 24V input.
9
Fault Indicator
This led indicates when the amplifier has a fault.
10
Peak Limit Indicator
This LED indicates when the input signal is clipping.
11
OverLoad Indicator
This LED indicates when the output is drawing too much current from the amplifier. The output will be
disconnected until the current draw is reduced.
12
OverTemp/ Half Power Indicator
When this LED is red it indicates when the amplifier is overheating. The output will be disconnected until the
amplifier is once again cool enough to operate. If thie LED is orange the amplifier has gone into half power mode.
This mode lets the amplifier continue to run at a lower output rather than shutdown completely. This mode might
be initiated from the amplifier being overdriven or overloaded.
13
Bass and Treble Controls
Use these controls to adjust the bass and treble.
14
Signal Presence Indicator
This LED indicates when an input signal is present.
15
Music Input
Use this input to connect a portable music player. This input over-rides the rear input 3 and is adjusted via the
volume 3 pot.
16
Vox level controls
Use these controls to adjust the vox sensitivities of inputs 1-2.
Model : A 4270
125W
Public Address Amplifier
24V
Signal
Protect
DC
Over
Load
Power
Local Music
Input
Treble
Bass
On
Master Volume
Volume 1
Volume 2
Volume 3
_
0
+
Present
VOX 1
Sens.
VOX 2
Sens.
Fault
Limit
Over Temp
Peak
16
1
2
13
3
6
7
8
9
10
11
14
15
0
2
4
6
8
10
0
2
4
6
8
10
0
2
4
6
8
10
0
2
4
6
8
10
_
0
+
1/2 Power
Out 1
BGM Output Select
Out 2
Out 3 Out 4
Status Indicators
Mic
BGM
Active
Mic
Paging
Active
Evac
Tones
Active
Normal
Mode
12
4
5
