User's Manual

BDA OPERATION
Refer to figure 3 for adjustment access location and label.
ALC (Automatic Level Control)
To minimize intermodulation products, each amplifier in the BDA contains an ALC
feedback loop. The ALC circuit senses the output power and limits it to the factory
preset level of +25 dBm.
ALC function is selected with an on/off toggle switch located on each amplifier and
accessible via the adjustment access panels located on the sides of the BDA
enclosure (Left, or “BASE” side is Downlink, right, or “MOBILE” side is Uplink). A red
indicator lamp located on each amplifier illuminates when output power exceeds the
ALC set point. The indicator is functional regardless of the position of the ALC switch.
Units are shipped with the ALC switch in the “ON” position.
MGC (Manual Gain Control)
BDA gain can be reduced by approximately 15 dB with screwdriver-adjustable
potentiometers located on each amplifier. The potentiometers accept a 3/32” slotted
screwdriver (provided), and are accessible via the adjustment access panels located
on the sides of the BDA enclosure (Left, or “BASE” side is for Downlink, right, or
“MOBILE” side is for Uplink).
When ALC operation is selected, the MGC remains the “master” gain control. MGC
cannot raise ALC set point above its factory preset level.
If operation below the 25 dBm ALC set point is desired, BDA gain can be reduced by
turning the MGC potentiometer clockwise until the light goes off.
Operation of BDA-XXX-1/1W-60-A at maximum gain with greater than -30 dBm
average power incident on either BASE or MOBILE port can cause damage to
the BDA.
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