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to continue it here, since I think that there are some issues discussed there which require

a little bit more clarification.

@berkeman responded in the linked discussion in #25 as follws:

"I think this is pretty close to correct. If the line segments are long enough to manifest TL

effects (and thus generate reflections), it is best to use matching networks to minimize

reflections and wasted energy. If the joining sections are short, the matching networks are

probably not needed. Note though that even RF connectors are designed for a particular impedance

generally, even though they are electrically short at RF frequencies."

I'm a bit confused about the statement that "If the joining

sections are short, the matching networks are probably not needed."

As far as I understand it correctly, in general case where the source ##S## and load ##L##

have complex impedances ##Z_S## and ##Z_L## there are two standard but different impedance matching methods known:

the maximal power transfer and the minimization of reflected signal waves (they only coincide if the impedances of source and load are real, ie resistive.

But in general setting that's not the case. So if we have such source and load with complex

impedances given and our goal is to match them, we should ask ourself a basic question

depending on the context "What is for us in THIS situation more important? To

maximize the transfered power to the load or to minimize the reflected waves?

As I said in general to obtain both simultaneouly is mathematically not possible

(see my opener #1 in https://www.physicsforums.com/threa...ne-and-load-impedances-are-different.1009266/ )

And now we come back to @berkeman's statement. If we deal with the case that

joining sections (=transmission lines) are short (with resp the used wavelenghts, I guess),

then we know that the wave reflection effects are neglectable.

So in this case the impedance matching should be focussed on the maximization of

power transfer, or not?

So I not understand why berkeman said there that in case of short joining sections NO

impedance matching is needed.

Doesn't this condition only exclude the neccessarity for carring for the signal reflection issues? But then since we can exclude the neccessarity for minimization of wave reflection, we can focus ourself on maximization of power transfer only, or not?

Or did I misunderstood the point there?