Jano OM8AAK is the author of an interesting article about PA, which he managed to compile for a few crowns. The base is a hybrid PA Mitsubishi M6779H2, which was purchased on the stock exchange for fifty crowns. The PA gives approximately 20W of power in the 70cm band.
After switching on, it is necessary to match c3-c7 at the input and at the output already for the reason that the integrated circuit is mainly intended for the frequency of 450-480 MHz. This setting adjusts its operating frequency downwards. It heats up especially during longer cranking.
If you need something more powerful and have more integrated circuits, go to the site https://www.QSL.net/dl4mea/70cmpa.htm.
73… OM8AAK