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A 2 stage 40w amp using 28v devices. RF input power should be between 0.5 and 1 watt. The diagram below shows a 2N3375 driving a 2N5643 but there are many other devices that will work. I used these 2 transistors just because they were cheap at the time. If any of the variable capacitors are at full capacitance you can pad them out with a fixed ceramic capacitor of suitable value. Extra capacitace also might be needed on the base of the transistors (i had to add 3 100pF capacitors on the base of the 2N5643).
heres a built example below. The transistors are bolted to a piece of right angle aluminium which is fixed to the metal chassis to dissipate heat effectively: