BDA OPERATION
Refer to Figure 2 & 3 for adjustment access location and label.
Variable Step Attenuator
BDA gain can be reduced by up to 30 dB in 2 dB steps using the variable step
attenuator. Gain adjustment is made with rotary switches accessible via the access
door on the BDA enclosure. Arrows on the shafts of these switches point to the value
of attenuation selected. BDA gain can be determined by subtracting the attenuation
value from the gain reported on the BDA Test Data Sheet for that side of the unit.
The attenuators are labeled for Uplink and Downlink.
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 +26 dBm.
ALC function is located on each amplifier and accessible via the access door on the
BDA enclosure. A red indicator lamp located on each amplifier illuminates when
output power meets or exceeds the ALC set point. The indicator is functional
regardless of the position of the ALC momentary switch.
To establish proper operating gain on the Uplink and Downlink sides, start with the
Downlink. Observe the red indicator lamp on the Downlink amplifier. Units are
shipping with maximum attenuation. Decrease attenuation one step at a time until the
lamp is lit. Then, using the Downlink step attenuator, increase the attenuation until
the lamp goes off. Repeat the process for the Uplink. The level indicator is accurate
to +/- 0.4 dB of the ALC set point.
Operation of BDA-PS7/PS8-2/2W-80-A at maximum gain with greater than -43
dBm average power incident on the MOBILE or BASE ports can cause damage
to the BDA.
Page 8
Summary of Contents for BDA-2W-80-A
Page 1: ...INSTALLATION AND OPERATING MANUAL BDA PS7 PS8 2 2W 80 A DUAL BAND BI DIRECTIONAL AMPLIFIER ...
Page 9: ...Figure 2 Uplink Adjustment Access Panel and Label Page 9 OFF ON ALC 0 30 UPLI NK ...
Page 10: ...Figure 3 Downlink Adjustment Access Panel and Label Page 10 0 30 DOW NLINK OFF ON ALC ...
