Re: QCX: Calculation of low pass filter for PA?


Kārlis Goba
 

You can use various networks for impedance matching, see this: https://home.sandiego.edu/~ekim/e194rfs01/jwmatcher/matcher2.html (the best calculator on this topic, but sadly the author is no more with us).

Depending on their topology, these networks can often be combined with the following lowpass section, e.g. parallel capacitors or series inductors merged into one.

However, it is still not entirely clear to me how the authors of your original link arrived at their component values. I bet they did it with good old clever analog design methods :)

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Karlis YL3JG

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