User's Manual

14221-1200-4010, Rev. B

11. Position the wattmeter’s 5-watt element to measure reverse (reflected) RF power from the antenna.

The arrow on the face of the element must point away from the antenna and towards the LBPA to

measure reverse power.

12. Turn on the MRU.

13. The wattmeter reading should be less than ½ watt.

14. If the wattmeter reading is within the range, record the value in the appropriate space on the data

collection form near the end of this manual (page 90).

If the wattmeter reading is outside the range, first verify the LBPA antenna’s driven element is

properly trimmed. Before making any antenna adjustments, be sure to disable the LBPA to stop

transmitting. Verify LBPA power supply voltage (i.e., battery voltage) is within the specified range,

recheck all connections, and measure the forward power again. If this fails to produce a reading

within the range, check all cabling and connections, and repeat the testing procedure to this point. In

the event the wattmeter reading still falls outside the range, replace the antenna, make sure all

connections are seated firmly, and repeat the testing procedure. If problems persist, contact the

Technical Assistance Center (see page see page 21).

15. Turn off the MRU. The LBPA should stop transmitting immediately, as indicated by the wattmeter.

16. Disconnect the coaxial cable jumper and wattmeter.

17. Permanently connect the LBPA antenna cable to the ANTENNA (TNC) connector on the rear of the

LBPA.

Improper installation of the RF cables may lead not only to poor radio performance

but also to harmful exposure to RF electromagnetic energy.

18. Use a pair of soft-jaw pliers to gently tighten this connection. Do not over tighten and do not twist the

antenna cable.

To prevent RF leakage and ensure peak performance, make sure the RF connectors are tight,

but do not over-tighten so connector damage will not occur.

19. Make several test calls on the radio system to verify MRU/LBPA operation. Before making the calls,

select another conventional channel(s), as required to verify operation.

NOTE