I'll put in my $0.02 and then be silent (I promise!).
At 10:42 AM 3/28/2002 -0500, Paul Christensen wrote:
> > If there's no termination, there's no power - for power, you have to have a
> > dissipating resistance.
>
>Correct in that the unterminated end of a line presents no load. Without
>a load on the of a transmission line, no power is
>dissipated.
>
>However, power is being generated and dissipated somewhere. Why? If I
>take my fixed output impedance transmitter and connect to an
>unterminated transmission line, my Bird 43 reads 100-watts of forward
>power and 100-watts of reflected power.
No. Watt meters that hams and most engineers use at RF measure either
voltage or Current. They do not measure *power*. Given the voltage or
current, analog meters use a graphical conversion (called a meter scale) to
equivalent power given under the assumption of a matched
termination. Digital meters also perform a conversion in firmware. None
of these devices measure *power*.
Kim Elmore, N5OP
Kim Elmore, Ph.D.
"All of weather is divided into three parts: Yes, No, and Maybe. The
greatest of these is Maybe" The original Latin appears to be garbled.
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