Lna Output Alarm Adjustment; Operational Check-Out; Forward Pa Channel Verification; Pa Output Level Verification - Andrew 2400 Operation And Maintenance Manual

385700-4006-006
2.5.2.3.3

LNA Output Alarm Adjustment

The previous step must be completed
before adjusting the output alarm.
Attach a voltmeter to J4-2 (LNA output Alarm test point) on the Alarm I/O board. TP1 or TP2
can be used as the ground connection.
Adjust R2 on the LNA until the voltage on J4-2 goes high (≥ 3 VDC), low (≤ 1.0 VDC), and
then high again.
Decrease the signal generator output as required to obtain a 10 dB drop in output level, from
the level set in the previous section, of the LNA channel.
Adjust R2 on the LNA until the voltage on TP2 goes low (≤ 1.0 VDC), high (≥ 3 VDC), and
then low (≤ 1.0 VDC) again. Increase the signal generator input by 10 dB and verify that the
output alarm signal at TP2 is high (≥ 3 VDC). Decrease the signal generator level by 10 dB
and verify that the output alarm signal at TP2 is low (≤ 1.0 VDC). Readjust R2 and repeat as
necessary.
Remove the SMA termination from the LNA module J5 Aux RF IN port and reattach the pilot
tone signal cable to the LNA module J5 Aux RF IN port.

2.5.3 Operational Check-Out

Attach a 2 watt or greater 10 dB power attenuator to the J3 and J4 ports of the DLA. From the
configuration documentation sent with the amplifier or using on site documentation that
reflects any changes from the factory settings, determine the output level settings of the PA
and LNA channels, the PA input alarm level, and the PA and LNA output alarm levels.
2.5.3.1

Forward PA Channel Verification

Set the DLA direction to the forward direction.
2.5.3.1.1

PA Output Level Verification

Attach either a signal generator (frequency = 2417 MHz) or a BDR to J4 (FWD IN/RVS OUT)
port of the Distribution Line Amplifier Assembly. Adjust the signal generator or BDR signal
level at J4 to 0 dBm ± 0.1 dB. Using a power meter verify that the signal level at the J3 (FWD
OUT/RVS IN) port of the Distribution Line Amplifier Assembly equals G
G is equal to the expected gain of the PA channel. If the gain is not equal to G
pa
dB, perform the steps outlined in section 2.5 for the PA output adjustment. If after completing
the amplifier setup procedure the output level of the PA channel is not G
Document use is restricted to that described on cover
NOTE
INSTALLATION
dBm ± 1 dB where
pa
dBm ± 1
pa
dBm ± 1 dB and all
pa
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