[Amps] Zener Screen Regulators

[gdaught6 at stanford.edu]

Bill wrote (over and over)

> >> I still ask for an explanation of why the filament or cathode in
> a tube has to
> >> be heated to receive the current flow. I've been asking this
> question for fifty
> >> years. Still waiting.

This is so easy.  The filament/cathode has to be brought up to a proper operating 
temperature to emit electrons.  When they are emitted, they can flow to other 
electrodes in the tube's envelope, right?  We measure the electron flux by a variable 
called 'current', which BY CONVENTION, is said to flow in a direction opposite to 
that of the actual motion of the electrons.  

It's not that hard.  It may not be what some folks like, but it's how it is.  Similar 
questions can be asked about the electric field, and the direction of a magnetic field 
around a conductor which is carrying a flow of electrons [expressed as a current].

73,

George T Daughters, K6GT
CU in the California QSO Party (CQP)
October 6-7, 2012