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amplifier. Relay switching time is approximately ten milliseconds. Radio adjustable TX
delay should be set to 10 mS.
This amplifier includes full metering using a large easy-to-read conventional cross-
needle panel meter. The meter reads all critical parameters, including Forward and
Reflected peak envelope RF power, voltage and, current.
Installation
Please look your amplifier and power supply over carefully. Observe the air inlet and
outlet ventilation holes. Facing the amplifier front panel, the cooling air inlets are on the
top left and lower right side, including the right hand side cabinet bottom. Warm air exits
vents at the cabinet rear.
While outlet air will not be particularly hot, it is never a good idea to have warm air blow
into heat sensitive equipment, such as transceivers or other power amplifiers. Have the
same consideration for your new amplifier and power supply. Be sure air inlet
temperature is not substantially above normal room temperature. Ideally, the air inlet
temperatures should be below 32°C or 90°F, although temperatures up to 41°C or
106°F are permissible. Should ambient temperatures exceed these limits, it might
become necessary to reduce duty cycle or power.
Warning:
Do not block cooling air inlets and outlets!
Never expose the amplifier to excessive heat, dirt, water, or mist.
Installation Clearances
The amplifier must have a clear area to the bottom, both sides, and top for proper
airflow, and to the rear for exhaust air and interconnection wiring. It is especially
important to avoid obstructions that block the air inlet on the top left, as well as both
lower sides. One to two inches clearance is normally adequate for full ventilation. Keep
any papers or loose objects that might impede airflow away from the air inlets and
outlets.
Locate the amplifier and power supply away from sensitive equipment such as
microphones, audio processing equipment, or low level audio or radio frequency
amplifiers. Generally, the best location for the power supply is below the operating desk
and away from antenna feedlines. This will minimize unwanted mechanical, acoustical,
and electrical coupling.
The power supply produces very little heat, but the air inlet and outlet must remain open
to normal room temperature air.
Installation Warnings
Accessory Equipment and Devices
Second to operator error, the most common amplifier failure or erratic fault protection
shutdown is from antenna switches, lightning protection devices, or baluns with lightning
spark gaps in high SWR coaxial lines. Do not use 50-ohm lightning protection devices
on lines with high SWR, such as between and antenna and antenna tuner. High SWR
can raise the RF voltage to above the voltage limits of the protection device so that it
arcs over. Be sure any lighting protection devices are in good working order and is rated
above the power level of the amplifier.
Summary of Contents for ALS-706
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