RadioBanter - View Single Post - 50 Ohms "Real Resistive" impedance a Misnomer?

July 16th 03, 06:58 AM

(Richard Harrison) wrote in message ...
Dr. Slick wrote:
"The funny thing about this is that you cannot say that the 50 ohms in
the center of the chart is a "resistive" 50 ohms as there is very little
real resistance in the average antenna."

Resistance is defined as real. That is, current is instantaneously
proportional to the voltage.

Any efficient antenna has a high ratio of radiation resistance to loss
resistance.

Ok, i stand partially corrected. I should have stated this:

"You cannot tell if the 50 Ohms reading on a Network analyzer into
a Black Box is a dissipative resistance like a dummy load, or if it is
a radiated resistance of a perfectly matched antenna. You don't have
that information."

Richard, I like your definition of real: "Resistance is defined
as real. That is, current is instantaneously proportional to the
voltage."

In other words, the V and I sine waves will be IN PHASE.

This clarifies it more for me. BOTH the radiation resistance and
the dissipative resistance of a dummy load are both "real" resistive
impedances.

Thanks,

Slick