56.Non-Harmonic Spurious Outputs, HP 8591EM Option 010

16.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 di￿erent if you are using another microwave spectrum analyzer.

a.Divide the marker frequency by the fundamental frequency (the EMC 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 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 di￿erence between the marker frequency and the frequency calculated in step c above. Continuing the example, the di￿erence 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 di￿erence calculated in step d is within the appropriate tolerance:

For marker frequencies <5 MHz, tolerance = 6200 kHz

For marker frequencies <55 MHz, tolerance = 6750 kHz

For marker frequencies >55 MHz, tolerance = 610 MHz

f.If the di￿erence 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.

17.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 16) and is a true response (see step 17), proceed with step 20.

Performance Veri￿cation Tests 2-357