Agilent Technologies N5241A, Руководство по обслуживанию

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Service Guide N5242-90001 3-35
PNA Series Microwave Network Analyzers Tests and Adjustments
N5241A/42A Performance Tests
Dynamic Accuracy Test
Function of the Test: To measure the relative power linearity of the analyzer’s receivers.
Specification Tested: Test Port Input–Dynamic Accuracy
Equipment Used: The dynamic accuracy test set (Z5623A Option H01), a power meter
(E4418B or E4419B), power sensors, and two test cables.
Description of the Test:
1. The analyzer’s test ports are tested separately at a specific CW frequency and a
reference power level of
−
20 dBm.
2. The analyzer’s driving port is connected to the dynamic accuracy test set’s source port
and the analyzer’s receiving port is connected to the dynamic accuracy test set’s
receiver port. A power sensor is connected to the dynamic accuracy test set’s power
meter port.
3. The dynamic accuracy test set is used to input a signal from the driving port on the
analyzer. The input signal is routed through step attenuators to both the analyzer and
a power sensor.
4. The analyzer source and the dynamic accuracy test set create power levels that are
“deltas” from the reference power level of
−
20 dBm. Each delta is measured two ways:
by the power sensor and by the analyzer’s receiver under test.
5. The analyzer’s power level into the port under test is set to the
−
20 dBm reference level.
6. The power level is measured with the power sensor: ( P
mr
).
7. The power level is measured using the analyzer’s receiver under test: ( P
pr
).
8. The power level into the analyzer’s port under test is stepped, in 5 dB steps, over the
range of 0 to
−
120 dBm. Each power level represents a “delta” from the reference power
level.
9. At each step, the power level is measured using the power meter: ( P
md
).
10. At each step, the power level is measured using the receiver under test: ( P
pd
).
11. The power error in dB
=
( P
mr
−
P
md
)
−
(P
pr
−
P
pd
) .
If the Analyzer Fails this Test:
• If the analyzer 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
“Removing and Replacing the A23 and A24 Mixer Bricks” on page 7-34 .
• If the analyzer still fails this test, replace the A12 SPAM board and repeat this test.
Refer to “Removing and Replacing the A4–A13 Boards” on page 7-14 .