Service manual
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Note:
The potentiometers do not have end stops. It is possible
to set the potentiometer in a dead band between the
ends, resulting in the audio being lost.
2.4.4 Overload LED.
The overload LED circuit monitors the amplitude of the
audio level entering the DSP module. The LED will
illuminate when the amplitude exceeds the maximum
permitted level. If the amplitude is increased further the
DSP will clamp the audio signal to prevent damage to
the DSP input. This will cause the audio signal to become
distorted. The optimum level is achieved when the
loudest peaks of the input audio, just cause the LED to
glow.
2.5 Module mounting.
The DSP module has four mounting holes that can be
used to retain the unit inside the equipment. Alternatively
a self adhesive pad is supplied to allow the module to be
mounted in a convenient position - without the need for
drilling.
Two holes need to be drilled in the casing of the
equipment for the keyboard. Hole sizes and positions
can be found in section 7.
The keyboard can retained using the supplied ‘Z’ bracket
or alternatively retained using a suitable adhesive, or
the mounting pads supplied.
In some equipment it may be possible to clamp the
bracket under the loudspeaker bracket.
Cover the keyboard holes with the supplied self adhesive
label.
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connection (this screens the cable and acts as a
mechanical fixing for the cable, protecting the capacitor
pads).
3.3.2 Power connections.
5 - 15VDC (9V typically) is required to operate the
module. The lower the voltage, the less heat the module
will have to dissipate.
Locate a convenient point to connect the power. Ensure
that this point is connected after the power switch,
otherwise the DSP module will be drawing power all the
time, and may flatten the batteries (where fitted). Connect
the red wire to this point.
The 0V connection is formed using the M3 ring tag.
Locate a suitable 0V point (such as a PCB retaining screw
that is fixed into the chassis).
When routing the wires, ensure they are away from strong
sources of RF or high voltage.