Vollane wrote:
when i watch a signal on an oscilloscope, what
am i looking at a flux of electrons or a flux of an
absence of electrons?

What you see is the light generated by the interaction of a beam of
electrons hitting the phosphor painted on the inside of the CRT (cathode
ray tube -- cathode rays are an old name for electrons emitted by a
cathode). The phosphor is just a chemical that happens to emit light
when excited by collisions from such an electron beam. The glass of the
CRT is more than enough to stop the electrons; they also generate some
X-rays, but for modern displays they are not a health risk.


Tom Roberts