In the steady state, the transmission line will be nothing more
than an impedance transformer. Depending on the load impedance
and the Zo of the line, and the length of the line, it will transform
the load impedance into what the source sees as an effective load.
Assuming the losses in the transmission line are negligible, the
power delivered to the load can be calculated based upon Steve's
"simple impedance calculation" using the effective load impedance
presented to the source. If there is no transmission line present, then
the simple impedance calculations can be done directly without any
accounting for transformer action.
73 de Mike, W4EF..................
----- Original Message -----
From: "Steve Thompson" <g8gsq@qsl.net>
To: <amps@contesting.com>
Sent: Saturday, May 26, 2001 2:20 AM
Subject: Re: [AMPS] Conjugate Matching and Efficiency
>
>
> -----Original Message-----
> From: Jon Ogden <na9d@speakeasy.net>
> To: Steve Thompson <g8gsq@qsl.net>; amps@contesting.com
> <amps@contesting.com>
To: <amps@contesting.com>
> Date: 26 May 2001 00:31
> Subject: Re: [AMPS] Conjugate Matching and Efficiency
>
>
> >
> >on 5/25/01 8:47 AM, Steve Thompson at g8gsq@qsl.net wrote:
> >
> >> For power to be reflected, doesn't the source have to be a transmission
> >> line? A series C can reduce the power delivered to a load just by adding
> >> reactance and increasing the overall impedance thus reducing the current.
> >
> >What do you mean "doesn't the source have to be a transmission line?"
>
> Nothing personal here, Jon, but I can't think of any other way to put it. In
> my mind, I can't see how you can have or measure forward and reflected power
> without a transmission line somewhere. Doesn't reflected power only happen
> when the termination on a transmission line doesn't equal Zo. I'm wide open
> to correction here.
> >
> >A series C can indeed do what you say. However, a true series C does not
> >dissipate energy but stores it.
>
> Indeed. The point I intended to make was that there are situations and
> impedances where simple impedance calculations are intuitively more useful
> than s parameters, but it didn't come over as clearly as I intended.
>
> Steve
>
>
>
> --
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>
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