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If the power output is less than expected, and if other test equipment is not available, then I suggest removing a turn or two from each of the toroids, similar to what Karsten DL3HRT and others have done.?

I think that in the event of the Low Pass Filter having attenuation which reduces the anticipated output, this power has to go *somewhere*... where it is going, is heat. So this is why when you have unwanted attenuation in the Low Pass Filter, people observe heating in the capacitors. 3dB of attenuation at 5W would mean 2.5W lost in the filter, as heat. No wonder, it gets hot... If a capacitor value is too low then this can also alter the shape of the response and cause attenuation at the transmit frequency. Again if you do not have test equipment and you want to be perfectionist, I would suggest just removal of a turn or two or few.?

If at any specific supply voltage, one person gets 3.5W, one person gets 4W and another gets 3W, then I think that this is nothing to worry about. In any case many people do not have accurate means of power measurement. If you get 1W when some others get 3, 4 etc., then this is probably an issue (as long as you are confident of your measurement). When measuring power always be aware of the limitations of the instrument! You must use a 50-ohm dummy load because many power meters will not read accurately if you are transmitting into an antenna - any SWR will just alter the measurement. Also do not trust power measurement readings before the Low Pass Filter, the waveform is not a sinewave and many power meters will therefore not read that accurately either.?

73 Hans G0UPL