ADCP-75-214 • Issue 2 • September 2006

4.5Return Loss Sweep Guide

RETURN LOSS SWEEP GUIDE FOR THE RECEIVE SECTION OF THE MHUs.

 

0

 

GOOD

 

BAD

 

 

 

 

 

 

-5

 

 

 

 

 

-10

 

 

 

 

 

-15

 

 

 

 

dB

-20

 

 

 

 

RL

 

 

 

 

-25

v1

v2

v1

v2

 

 

 

 

 

 

-30

-35

-40

-45

NORMAL IN-SYSTEM SWEEP. TYPICAL.

DEGRADATION FROM NORMAL SYSTEM SWEEP.

 

RL IS STILL GOOD IN RX BAND.

 

RECOMMEND CONNECTOR/LINE/ANTENNA CHECKS

 

DURING NEXT SCHEDULED MAINTENANCE PERIOD WHEN

 

TOWER CREW AVAILABLE.

RESISTANCE LOOKING INTO THE FEEDLINE SHOULD INDICATE HIGH OR INFINITE OHMS.

RL dB

0

-5

-10

-15

-20

-25

-30

-35

-40

-45

GOOD

BAD

v1

v2

v1

v2

ANTENNA PORT: TERMINATED WITH 50 OHM LOAD.

 

ANTENNA PORT: ANTENNA CATASTROPHICALLY

 

"PERFECT ANTENNA" < 50 OHM LOAD >

 

FAILED "OPEN".

 

 

 

 

ANTENNA PORT: ANTENNA CATASTROPHICALLY

 

 

 

 

FUSED "SHORT".

 

 

18270-A

Page 17

© 2006, ADC Telecommunications, Inc.