6-2
Antenna and transmission line tests
411-2051-500
Draft
00.01
November 1999
Antenna return loss
The antenna return loss is measured to verify that the antenna is properly
matched to the system and to identify open connectors.
Antenna return loss test
This test uses the signal generator, the spectrum analyzer and the VSWR
bridge to sweep the antenna for return loss at both the receive (824 to 849
MHz) and transmit (869 to 894 MHz) frequency bands. Figure 6-1 shows the
set up for the test.
Test Equipment:
RF Signal Generator
Spectrum Analyzer
VSWR Bridge
If any of the test equipment is not available, a Thruline Wattmeter may be
used (refer to the Thruline Wattmeter Method section).
Step
Action
Observation
1
Visually inspect the bonding of the
transmission line to the mast ground riser at
both the top and bottom of the tower.
The transmission line must be bonded at
both the top and bottom. A set of binoculars
or a spotting telescope may be required to
verify the upper bonding.
2
Inside the building, measure the DC
resistance of the outer conductor to the
principle ground.
Less than or equal to 0.5
Ω
3
Measure and record the DC resistance of the
center conductor (pin)to the outer
conductor(shield).
4
Also check the alignment of the center pin of
the heliax connector. If necessary re-align
the centre pin so that the female pin in the
antenna jumper cable connector is not
damaged.
Repair or replace heliax, connectors, ground
systems as required.
CAUTION
This test is service affecting when the antenna is disconnected.
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Страница 6: ...vi Publication history Nortel Networks Confidential 411 2051 500 Draft 00 01 November 1999...
Страница 82: ...2 20 Periodic maintenance 411 2051 500 Draft 00 01 November 1999...
Страница 90: ...3 8 Test equipment and precautions 411 2051 500 Draft 00 01 November 1999...
Страница 100: ...5 6 Master Oscillator tests 411 2051 500 Draft 00 01 November 1999...
Страница 106: ...6 6 Antenna and transmission line tests 411 2051 500 Draft 00 01 November 1999...
Страница 116: ...8 4 Alarm Control Unit ACU tests 411 2051 500 Draft 00 01 November 1999...
Страница 138: ...10 2 ICRM tests 411 2051 500 Draft 00 01 November 1999...
Страница 200: ...12 10 Enclosure maintenance 411 2051 500 Draft 00 01 November 1999...
Страница 208: ...A 8 Appendix A Frequency table 411 2051 500 Draft 00 01 November 1999...
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