Cecil Moore wrote:
Alan Peake wrote:
But I still can't see that a virtual short would be different to a
real short.

I forgot to say, the following applies only to a virtual
short in the absence of a physical impedance discontinuity.
A virtual short at a physical impedance discontinuity
involves interference between forward wave components and
reflected wave components.

A virtual short is (Vfor-Vref)/(Ifor+Iref) = 0
where |Vfor| = |Vref|

For the virtual short to exist, two equal magnitude
EM waves have to be *flowing through* the virtual
short. EM waves *cannot flow through* a real short.

For real shorts:
V/I=0 is a result caused by the real short.

For virtual shorts:
A virtual short is a result caused by V/I=0.
--
73, Cecil http://www.w5dxp.com