Technical data

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Chapter 4, Test, Parameter, and Pass/Fail Limit Descriptions

TEST_14. RX Usable Sensitivity

This test measures the RF signal level required to produce the standard SINAD

ratio (determined by

Parameter 18, RX Usable Sens Set and Measure the “usable

sensitivity SINAD level”) at the output of the receiver. Audio connections from

the radio to the test set are required for this test.

This test can be run in two different ways:

• The first method is the “iterative” test where Parameter 17, RX Tolerance for

Setting Volume is set to “0”. In this case, usable sensitivity is measured at 60% of rated

system deviation at a 1 kHz rate. The volume is checked to verify that it has not

decreased by more than 3 dB. The measured usable sensitivity is reported in the test

results and compared to Pass/Fail Limit 13, RX Squelch Blocking to determine if the

test passed or failed.

• The second (and faster) method is the “set and measure” test where Parameter 17,

RX Tolerance for Setting Volume is set to “1”. In this case, usable sensitivity is

measured by setting the RF level to the upper limit of Pass/Fail Limit 13, RX Squelch

Blocking and SINAD is measured to determine if the test passed or failed.

Pass/Fail Limits Used

Pass/Fail Limit 17, RX Usable Sensitivity

Test Parameters Used

Parameter 1, RT External Pad and Cable Loss

Parameter 11, RX Maximum Audio Power

Parameter 16, RX Standard RF Input Level

Parameter 17, RX Tolerance for Setting Volume

Parameter 18, RX Usable Sens Set and Measure

Parameter 19, RX Usable Sensitivity SINAD Level