10Base-T Harmonic Content
1000BASE-T/100BASE-TX/10BASE-T Physical Layer Compliance Tests Manual
72
Intel Confidential
3. Adjust the spectrum analyzer as indicated below.
4. Place a marker on 10 MHz (fundamental frequency) and the highest amplitude harmonic (must
be a multiple of 10 MHz) between 6 MHz and 206 MHz. The figure below provides a
reference.
Note:
For a better display, The end frequency can be reduced to be closer to the frequency of the highest
amplitude harmonic. The signal may need to be attenuated if it is out of range on the spectrum
analyzer.
5. Record dBm at 10 MHz and dBm at highest amplitude harmonic. The difference between the
two markers must be greater than 27 dBm to ensure compliance with IEEE standards and
specifications.
6. Verify the measurements meet specifications.
Table 18-1. Analyzer Configuration for Harmonic Content
Scope Parameter
Settings
Start Frequency
6 Mhz
Stop Frequency
206 MHz (a pre-scan to 500 MHz is okay)
Resolution BW or IF BW
Lowest practical BW supported by equipment
in the range of 10 KHz and 200 KHz.
Number of Points (Resolution)
Maximum for instrument (
≥
401)
Acquire
Average (if necessary)
Vertical Division
10 dB/division
Mode
Spectrum Analyzer