Tal --

> Are "Artificial Earth" can be made only if you build your switching PSU or
> it can be made with other methods?

Yes, to get true galvanic isolation you need to generate AC so that you
can push energy through a pair of capacitors (very low-power systems) or
a transformer (most other systems).

The only other option would be a bright light and a photocell -- very
inefficient, but might be useful in certain applications.

-- Dave Tweed

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