OK, so I've been trying to learn how to calculate RF matching networks for a while, but I keep getting frustrated because I can't seem to find any good resources.

So it looks like the matching network on the circuit I'm looking at uses an LCC type.

On the input it is 2 x 56p one in-line and one to ground and then a 150nH in line.

On the output is a ~27nH in-line and 62p to ground, and 1nf in-line.

The MOSFET is RD06HVF1. How do people arrive at these values? What are the caluclations?

The best book is "Solid State RF Power" by Raab. It's unsurpassed, but will cost you about £180 for a copy (unless you can find a bootleg pdf copy on-line).

I'll be happy to run a short series of tutorials if anyone's interested, but beware - there's some fairly abstruse mathematics involved. You need to have a good grip of algebra, some basic calculus and complex number theory. An understanding of trigonometrical identities is also a time saver.

Designing an RF power amplifier isn't trivial. Most pirates take the "copy someone else's" approach. In all the time I was building rigs in London, I can name the five or six originators of virtually every circuit that was used. Myers, Richard C, Roger P, Martin, Me, Roger H..... I can't think of anyone else

I used to deliberately use some unnecessarily obscure component values in my circuits, so it was easy to see who was copying my designs! At one time I accidentally managed to corner the world market in 51pF capacitors - I had boxfuls of them - and used them in almost every stage of a run of exciter boards. All the component shops in London (and beyond) got fed up with the endless requests for 51pF ceramic capacitors. What the clueless copiers didn't realise was that in most cases, 47pF or 56pF would have worked just as well!

I found this this book in pdf it's co written by F H Raab with Krauss and Bostian, Solid State Radio Engineering from 1980, i'm not sure if it's the same book Albert refers to, but looks to be a good read if your into radio.

http://www.csun.edu/~ih20409/SCHOOL1/So ... .1980).pdf

shorty wrote: ↑Mon Jun 05, 2017 3:31 pm I found this this book in pdf it's co written by F H Raab with Krauss and Bostian, Solid State Radio Engineering from 1980, i'm not sure if it's the same book Albert refers to, but looks to be a good read if your into radio.

http://www.csun.edu/~ih20409/SCHOOL1/So ... .1980).pdf

The Krauss, Bostian & Raab book is a superb primer for the principles of radio engineering. Some University courses use it (still). My copy is rather worn. The ISBN is 0-471-03018-X and you can get it from specialist book shops (though it's very expensive!).

Here's my copy:

Another very popular book is RF Circuit Design by Chris Bowick. He tells you how to use the Smith Chart, design matching networks and build filters, etc etc. Also very affordable.

The problem you're going to have with your RD06 circuit is working out the input impedance; a lot of the Japanese datasheets lack proper data and give you the optimum impedance at some random frequency making it hard to know where to start. Luckily this can be done experimentally by using a single LC matching network which is uses a trimmer and variable inductor and some means of measuring the input match (S11). The output is more straightforward and can be found in the books!