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8. The ALC control is usually properly adjusted if the ALC LED just flashes when the
desired peak output power is reached. The audio or power output control on the
exciter can be adjusted to control how "heavily" the ALC is used. The higher the
exciter power (gain) control is adjusted the more compression the ALC circuit
provides.
The best signal quality occurs when the ALC LED occasionally flashes. The most SSB
signal "punch" will occur if the LED continuously flashes.
Full output levels of 500 watts CW should be obtained with drive levels of under 100
watts. Peak envelope output levels on SSB may reach as high as 800 watts depending on
voice and exciter characteristics. The lowest IMD and splatter will be obtained if the
amplifier is operated at an output level slightly below the maximum level obtainable.
Periodic Maintenance
The lack of extremely high voltages in this unit eliminates the chance of dirt and dust
causing high voltage arcing. The only requirement for periodic maintenance is to
monitor the amount of dirt and dust in the amplifier and the power supply. Whenever
there is a noticeable accumulation of dust that may affect cooling, air can be used to
blowout the equipment.
The fan area on the amplifier should be inspected every few months if the amplifier is
operated in a very dusty environment. If there is a large amount of dust on the fan it is
probably a good time to blow the dust out of the amplifier and power supply with
moderate air pressure.
A soft bristled brush and a small amount of alcohol can be used to clean stubborn dust
from the fan screen or the other components. Be careful not to get any cleaning
compounds on the relay contacts or the switches.
Caution: Never remove the cover of the amplifier or the power supply, with the power
supply plugged in to the electrical outlet.
