HP ESA-L1500A, Руководство пользователя и калибровки

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Chapter 9 305
Performance Verification Tests
24. Non-Harmonic Spurious Outputs, Options 1DN and 1DQ
14.Verify that the marked signal is not the fundamental or a harmonic
of the fundamental by performing the following steps:
Note that the following steps are for an HP 8566A/B microwave
spectrum analyzer, the steps may be different if you are using
another microwave spectrum analyzer.
a. Divide the marker frequency by the fundamental frequency (the
spectrum analyzer center frequency setting). For example, if the
marker frequency is 30.3 MHz and the fundamental frequency is
10 MHz, dividing 30.3 MHz by 10 MHz yields 3.03.
b. Round the number calculated in step a to the nearest whole
number. In the example above, 3.03 should be rounded to 3.
c. Multiply the fundamental frequency by the number calculated in
step b . Following the example, multiplying 10 MHz by 3 yields
30 MHz.
d. Calculate the difference between the marker frequency and the
frequency calculated in step c above. Continuing the example, the
difference would be 300 kHz.
e. Due to span accuracy uncertainties in the microwave spectrum
analyzer, the marker frequency might not equal the actual
frequency. Given the marker frequency, check if the difference
calculated in
step d is within the appropriate tolerance:
For marker frequencies <5 MHz, tolerance =
±
200 kHz
For marker frequencies <55 MHz, tolerance =
±
750 kHz
For marker frequencies >55 MHz, tolerance =
±
10 MHz
f. If the difference in step d is within the indicated tolerance, the
signal in question is the fundamental signal (if the number in
step b = 1) or a harmonic of the fundamental (if the number in
step b >1). This response should be ignored.
15.Verify that the marked signal is a true response and not a random
noise peak by pressing
SINGLE
to trigger a new sweep and press
Peak
Search
. A true response will remain at the same frequency and
amplitude on successive sweeps but a noise peak will not.
If the marked signal is not the fundamental or a harmonic of the
fundamental (see
step 14 ) and is a true response (see step 15 ), proceed
with step 17 .
16.If the marked signal is either the fundamental or a harmonic of the
fundamental (see step 14 ) or a noise peak (see step 15 ), move the
marker to the next highest signal by pressing
SHIFT
,
Peak Search
.
Repeat step 14 .
The following step is only performed if the marker signal is not the
fundamental or harmonic of the fundamental and is a true response.