Noise Floor Test - Keysight Technologies N5244/5B Service Manual

Tests and Adjustments
Performance Tests
11.The magnitude and phase measurements using the receiver under test are
read: (Pc).
12.The first test set output attenuator is set to 0 dB.
13.The magnitude and phase measurements using the receiver under test are
read: (Pd).
14.The compression for each point is calculated as (Pa–Pb) – (Pd–Pc).
If the Analyzer Fails this Test:
— Run the Receiver Characterization adjustment, and repeat this test.
— If the analyzer still fails this test, 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
on page

Noise Floor Test

Function of the Test: To measure the absolute power level of the noise floor for
the analyzer's receivers.
Specification Tested: Test Port Input–Test Port Noise Floor
Equipment Used:
— Power meter
— Power sensors
— Test cable
— Calibration kit
Description of the Test:
This test uses the source signal out of one analyzer test port as part of the
noise floor measurement on another test port. Port 2 is the source port when
measuring the noise floor of Port 1. Port 1 is the source port when measuring
the noise floor of Ports 2, 3, and 4.
1. The analyzer is Preset.
2. The analyzer is set up for a CW transmission measurement between the
source port and the test port to be measured. The analyzer is set to an IF
bandwidth of 1 kHz and 801 points per sweep.
3. A test cable is connected to the source port.
4. A power sensor is connected to the end of the test cable with any
necessary adapters.
5. For hundreds of frequencies across the analyzer's full range, a source
power calibration is performed to ensure a flat power response at the end
of the cable at the Preset power level.
3-38
"Removing and Replacing the A27 and A28 Mixer Bricks"
7-48.
Keysight N5244B/45B Service Guide