Stefan Wolfe wrote:
"Roy Lewallen" wrote in message
...
Stefan Wolfe wrote:

In a resonant circuit containing R, L, and C, there most definitely is a
time constant. Related to Q, it describes the time taken for the circuit
to respond to a transient. The higher the Q, the longer the time constant,
and the longer it takes the circuit to come to equilibrium after a step or
sinusoid is applied, and to decay after it's removed. Failure to
understand this has resulted in some very poorly designed audio filters
for CW, among other things.

But Roy, I must first clear up that we are talking about apples and oranges.
I was referencing a sinusoidal source of a frequency that is resonant to the
circuit. You are talking about a transient can be treated as the sum of
sinusoids which will not be resonant at the same curcuit. I was also
referring to the antenna as a L-C-R circuit that does have time constants
along its lengths (but I was asking 'where' along the length) but as a
whole system the time contant of the antenna, when fed by a signal at
resonant frequency is zero.
. . .

You've lost me. What is the meaning of a "time constant" in steady
state? What effect does it have? With a single frequency of constant
amplitude, how could you tell whether a circuit, resonant or not, has a
"time constant"? How could you measure it?

Roy Lewallen, W7EL