5 return loss sweep guide, Return loss sweep guide, Section 4.5 – ADC ClearGain Dual Inline Tower Mounted Amplifier System User Manual
Page 23
ADCP-75-214 • Issue 2 • September 2006
Page 17
© 2006, ADC Telecommunications, Inc.
4.5
Return Loss Sweep Guide
0
-5
-10
-15
-20
-25
-30
-35
-40
-45
RL dB
v1
v2
v1
v2
18270-A
0
-5
-10
-15
-20
-25
-30
-35
-40
-45
RL dB
v1
v2
v1
v2
RETURN LOSS SWEEP GUIDE FOR THE RECEIVE SECTION OF THE MHUs.
GOOD
BAD
RESISTANCE LOOKING INTO THE FEEDLINE SHOULD INDICATE HIGH OR INFINITE OHMS.
GOOD
BAD
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.
ANTENNA PORT: TERMINATED WITH 50 OHM LOAD.
"PERFECT ANTENNA" < 50 OHM LOAD >
ANTENNA PORT: ANTENNA CATASTROPHICALLY
FAILED "OPEN".
ANTENNA PORT: ANTENNA CATASTROPHICALLY
FUSED "SHORT".