Specifications

PA250 Series High Power Voice Amplifier
SM44-1 Installation and Operation Manual
April 22, 2012 Rev: 2.00 Page 3-3
ENG-FORM: 806-0100.DOTX
CONFIDENTIAL AND PROPRIETARY TO ANODYNE ELECTRONICS MANUFACTURING CORP.
3.3.4 AUDIO POWER (Level) Meter
The AUDIO POWER meter indicates the audio voltage going to the speaker load. The meter is calibrated
so that the pointer will be in the red area of the display at full power with the proper load.
Note: If the load is incorrectly connected, an erroneous meter reading will be given.
3.3.5 OVERLOAD Indicator LED
The PA250 Series amplifier is designed with self-protecting circuitry to interrupt operation whenever
unusual conditions exist which might endanger the amplifier components. Such conditions might be
excessive voltage, a voltage spike, a speaker short or a temperature rise. The OVERLOAD indicator will
illuminate red to notify the operator that the protective circuitry has been activated. See Section 3.3.6 for
‘Reset’ information.
3.3.6 Resetting the Protective Circuit
Once the protective circuit is activated, the OVERLOAD indicator LED will illuminate red and no further
operation is possible without corrective action. If the trouble was due to a temporary or transitory cause,
operation may be resumed by simply selecting the power switch to OFF and back to ON. If the protective
circuit again shuts the amplifier off, the POWER switch should be turned off and the problem diagnosed
and corrected before further use of the unit is attempted.
CAUTION:
The transistors of this system are subject to damage when exposed to excessive heat, voltage,
or current for even short periods of time.
The PA250 Series incorporates a protective circuit, which disables the amplifier when safe
operating currents or voltages are exceeded. The protective circuit is adequate in most
instances however, it is also subject to damage when the unit is exposed to extreme or
sustained stresses. Careful monitoring is therefore necessary when operating under unusual
environmental extremes. Precautions should be taken to maintain temperature within
recommended limits. Other damaging conditions are excessive battery charging voltages, short
circuits within the system and transmission of compressed high level music resulting in
continuous high-level power generation.
Operation at high temperature should be limited to short periods. Even at normal temperatures,
operation at continuous full power (Level meter in the red) should be interrupted for 5–10
seconds at 15-second intervals.
Loudspeakers will overheat with a continuous signal at full power. Voice operation will generate
less heat, and pauses between words will result in a low duty cycle.
Section 3.0 ends