52 Keysight Agile Signal Generator Service Guide
Troubleshooting
Troubleshooting Harmonic Spurious
Harmonics are multiples of the fundamental output frequency produced by a
signal generator. Specifically, the second harmonic is two times the output
frequency and its amplitude is measured relative to the fundamental (carrier)
output frequency amplitude; the power lever of a harmonic is expressed as
-xx dBc.
— If the frequency of a harmonic falls beyond the frequency range of the signal
generator, that particular harmonic is not specified or measured.
— If the frequency of a harmonic falls within the frequency range of the signal
generator, the harmonic’s power level is obtained with the following
procedure:
1. Set the signal generator and spectrum analyzer to the same
harmonic frequency.
2. Set the signal generator to a specific power level. Its output peak
power level is measured on the spectrum analyzer; this peak power
level is the reference level used for the harmonic measurement.
3. Set the signal generator to the fundamental frequency. The power
level of the fundamental frequency is measured by using Peak Search
and Marker Delta.
This measurement obtains the power level of the harmonic and is
expressed as a dBc value; it is the difference between the
fundamental peak power level and the harmonic frequency power
level.