Keysight N5227B, Руководство по обслуживанию

Страница: 66 / 415

3-40 Keysight N5227B Service Guide
Tests and Adjustments
Performance Tests
3-
6. The test set’s output attenuator is changed in 5 dB steps from 0 to 60 dB,
and this measurement is repeated.
7. With the 1 dB of overlap in each measurement, the data for each
attenuator setting can be stitched together to provide a complete receiver
linearity profile from +3 dBm to -63 dBm.
8. This test is repeated for each receiver.
If the Analyzer Fails this Test:
— If the analyzer fails this test, rerun the test.
— If the analyzer fails this test repeatedly, replace the A23 mixer brick for a
Port 1 or Port 2 failure or the A24 mixer brick for a Port 3 or Port 4 failure,
then repeat this test. Refer to “Removing and Replacing the A27 and A28
Mixer Bricks” on page 7-39 .
— If the analyzer still fails this test, replace the A12 SPAM board and repeat
this test. Refer to “Removing and Replacing the A4–A17 Boards” on
page 7-17 .
Dynamic Accuracy at Low Frequency (Available with LFE Option
205/220/420/425)
This description applies to all instruments with low frequency extension (LFE)
Option 205, 220, 405, 420, and 425.
Function of the Test: This test will be set to the LFE path at 99.6 MHz. The test
procedure is the same as the Dynamic Accuracy test process except that the
LFE test process uses a 2-channel function generator as the source which has
sufficient power range to cover each power step. Therefore a test set is not
required.
Specification Tested: Dynamic Accuracy at Low Frequency
Equipment Used:
— Function generator (33622A)
— Power splitter (11667B)
— Fixed attenuator (10dB x2) – (8493C Option 010)
— Four test cables