Installation guide

Troubleshooting
Troubleshooting Harmonic Spurious
1-103
To Verify Harmonic Performance at the Coherent Carrier Output
1. Signal Generator Settings
a. Set the frequency of the signal generator to the fundamental frequency being measured.
For example, when planning to measure the second harmonic of a 1 GHz signal
(which would be 2 GHz), set the frequency of the signal generator to 1 GHz.
b. Set the power level of the signal generator to +4 dBm (+7.5 dBm for Option UNB).
2. Spectrum Analyzer Settings
a. Connect a spectrum analyzer to the Coherent Carrier Output connector of the signal generator.
b. Set the frequency of the spectrum analyzer to the fundamental frequency being measured.
To continue with our example, set the frequency of the spectrum analyzer to 1 GHz.
c. Press the
Peak Search and Marker Delta keys.
The Marker should indicate approximately 0 dBm.
d. Set the frequency of the spectrum analyzer to the harmonic frequency being measured.
To continue with our example, set the frequency of the spectrum analyzer to 2 GHz.
e. Press the
Peak Search key and read the power level (and record it for future reference in case further
troubleshooting is necessary).
The Marker should indicate the harmonic power level in dBc.
f. Compare the power level of the Marker against the specified harmonic performance level for your
signal generator.
Filtering on the A13 Output should improve the harmonic performance at the RF Output versus the
Coherent Carrier output. However, the magnitude of this difference changes with frequency and actual
harmonic content. Therefore, it is hard to define an absolute acceptable harmonic level at the
Coherent Carrier output.
• If the harmonic level at the Coherent Carrier output is significantly higher than the harmonic level
of the RF Output, the most likely causes are one of the following:
— Signal Generators with Option 501, 502, 503, 504,
replace the A17 Synthesizer (Option 501, 502, 503, 504) followed by the A13 Output.
(Refer to “A17 Synthesizer (Option 501, 502, 503, 504)” on page 2-40
and “A13 Output” on page 2-32.)
— Signal Generators with Option UNJ or Option 506,
replace the A16 Frac-N (Option UNJ or Option 506) followed by the A13 Output.
(Refer to “A16 Frac-N (Option UNJ or Option 506)” on page 2-38 and “A13 Output” on page 2-32.)