How about that. Here we use silver plated tank circuits and large spaced caps.
I checked, the QST is not the april edition.
Also notice the simple pi-L filter in the output. Guess the rice boxes
are charging us for fancy output filters that we dont need to pass the FCC spec
for harmonic reduction.
My first impression of this circuit is that the ARRL tech board didn't
review it. W1FB has written many articles on the use of switching FETs for RF
generation. He has never claimed more than 50% at low frequencies and dropping
rapidly as the frequency is raised.
I have built amplifiers and blown FETs trying to get above 35-50 watts.
It is an interesting thought that some way we can build single band amps for 10
cents a watt.
Looking forward to part 2 to find out what the magic in the " switched"
or "keyed" power supply is all about.
de NO2T -Jerry
PS: look at the april 89 QST for what W1FB says about switching FETs.
end
NO2T Jerry
no2tj@cybernex.net
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