User's Manual

LNA - Low Noise Amplifier
The LNA low noise amplifiers are located in the outermost boxes at the
top of the cabinet and large cover (see Figure 5-1 to Figure 5-4 on
page 5-4 to 5-7). LNA/UL (uplink) is located to the left and LNA/DL
(downlink) to the right. All coaxial connectors are SMA type.
Signals from the duplex filter output is fed to the LNA input connector
IN. Output OUT1 and OUT2 feed the CHA boards of the same signal
direction. The signal level in these connectors are +20dB referred to the
antenna input. Another output, OUT LOW, is an expansion output for an
additional LNA amplifier, if the repeater is equipped in the cover part of
the chassis. The gain to this connector is +2dB.
The +7V input is used for 7V supply from the DIA board.
ATT is a control signal for a controllable attenuator in the LNA.
Connection
To the left in the cabinetLNA/UL:
Port Connected to
OUT LOW IN on the LNA/UL in the cover if equipped.
IN LO on the DPX/MS duplex filter.
ATT P23 on the DIA board.
+7V P23 on the DIA board.
OUT1 P101 on the CHA3/UL or CSA/UL or BSA/UL board.
OUT2 P101 on the CHA4/UL channel board.
To the right in the cabinetLNA/DL:
Port Connected to
OUT LOW IN on the LNA/DL in the cover if equipped.
IN HI on the DPX/BS duplex filter.
ATT P24 on the DIA board.
+7V P24 on the DIA board.
OUT1 P101 on the CHA1/DL or CSA/DL, or BSA/DL board.
OUT2 P101 on the CHA2/DL channel board.
Not used outputs do not need to be terminated.
OUT
LOW
IN ATT +7VOUT1 OUT2
LNA
UL
OUT
LOWIN+7V ATTOUT1 OUT2
LNA
DL
Figure 5-9. LNA low noise amplifier
ALLGON System AB AR Repeaters & OMT32 Hardware – Functional Description
User’s Manual VD202 90/EN Rev. 1A 1999-07 5 - 18