locked Re: Understanding USB and PC noise


You have not been listening. "Ground is not ground." That is one of Joanne's Laws. It simply means you are deluded if you think the ground over there is the same as the ground over here even if the distance between here and there is in fractions of an inch.

In a word, no. Ground isn't ground. And data does not like to be bypassed to ground giving it round edges and reduced amplitude.


On 20180416 16:17, Bryon NF6M wrote:
I wonder, as far as RFI coming in on the USB cable itself, would it help to add some RF bypass capacitors from the USB data/power lines to ground within the HF+?
It seems like that would essentially short any stray RF to ground at the connector, while allowing DC signals and power to remain unaffected.
Or would that distort the rise/fall of DC transitions on the data lines?

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