Agilent Technologies 8590 Series Service Manual page 577

5. A12 Step-Gain Check and error message STEP
GAIN/ATTEN FAIL.
The test checks the switching of the step gains on
the A12 amplitude control assembly. The test does
not check step-gain accuracy. The test steps the
reference level from −60 dBm to +30 dBm, in 10 dB
increments, with the input attenuator set to 60 dB.
The test detects step-gain switching activity by
comparing the noise-floor level for each 10 dB step
gain.
If the error message STEP GAIN/ATTEN FAIL is
displayed, the displayed noise level did not decrease
when the reference level was changed.
6. 3 dB Resolution-Bandwidth Check and error
message RES-BW SHAPE FAIL.
The test checks the 3 dB resolution bandwidth of the
10 kHz, 30 kHz, 100 kHz, 300 kHz, 1 MHz, and
3 MHz bandwidth filters.
If the error message RES-BW SHAPE FAIL is
displayed, the bandwidths that are displayed with
the error message are not within ±20%. Resolution
bandwidth accuracy is a characteristic, not a
specification. Check the failed bandwidths manually
using the
Chapter 13
softkey.
3 dB POINTS
Softkey Descriptions
Softkey Descriptions
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