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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 

Содержание BDA-PS8-2

Страница 1: ...INSTALLATION AND OPERATING MANUAL BDA PS7 PS8 2 2W 80 A DUAL BAND BI DIRECTIONAL AMPLIFIER...

Страница 2: ...ONS 4 MECHANICAL SPECIFICATIONS 5 ENVIRONMENTAL CONDITIONS 5 BDA CONNECTIONS 5 MECHANICAL OUTLINE DRAWING Figure 1 1a 6 BDA INSTALLATION 7 BDA OPERATION 8 UPLINK MECHANICAL OUTLINE ADJUSTMENT Figure 2...

Страница 3: ...from the base station and amplifies and transmits them to the subscriber The BDA Uplink path receives RF signals from the subscriber and amplifies and transmits them to the base station The Uplink and...

Страница 4: ...26 dBm Isolation between Up Down Link 100 dB min Input Output Impedance 50 Ohms VSWR Input Output 1 5 1 max Pass band Gain min attenuation 80 dB minimum Power Supply 110VAC 1 42Amp 240VAC 0 71 Amp 50...

Страница 5: ...connector provides failure alarm output contacts see diagram next page as well as an optional 12 VDC 250mA auxiliary output The RF connections are made via two type N female connectors The RF connecto...

Страница 6: ...ine Figure 1a Relay Shown in Non Alarm Condition The alarm monitors current of both uplink and downlink amplifiers An alarm condition will occur if either uplink or downlink amplifiers are over or und...

Страница 7: ...to the BDA connector labeled BASE and the cable from the service antennas to the BDA connector labeled MOBILE 4 Open the adjustment access panels on the sides of the BDA and verify that both of the a...

Страница 8: ...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...

Страница 9: ...Figure 2 Uplink Adjustment Access Panel and Label Page 9 OFF ON ALC 0 30 UPLI NK...

Страница 10: ...Figure 3 Downlink Adjustment Access Panel and Label Page 10 0 30 DOW NLINK OFF ON ALC...

Страница 11: ...quires no periodic maintenance There are no user serviceable components inside the BDA This section covers possible problems that may be related to the installation or operating environment a Gain Red...

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