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RE: RJ-45 common mode radiated emissions testing

Title: RE: RJ-45 common mode radiated emissions testing

I agree with you.

Keep in mind that open ended data cables are a very common as well as a valid test setup for radiated emissions.
That is why I tested using this setup, I wanted the worst case to help shed some light on an upper bound for DTE
power supply common mode noise. This applies equally to the PSE and the PD, since either end can be a source of noise.

More testing is needed.
For instance, I would like to see the test results from injecting a sine wave signal, in the "pair to pair" mode,
into the "spare" (as well as data pairs) so that the same mode is excited as will be with a power supply.
The collected data would consist of voltage levels of the injected signal that cause any increase in 10/100/1000 data errors,

at injection frequencies of 100 kHz to 30 MHz. This frequency range is not strictly covered by radiated emissions, yet
is important for power supply output spectrums.

- Rick