A year or two ago there was a discussion on the wildly accepted practice of
shorting out unused sections of a PI or PI-L output tank when not in use.
One commentator gave an exception that when toroids were used, shorting out
part of the inductor could be problematic. I do notice that several of the
latest ARRL Handbooks do exactly that in their "Saint Petersburg" amplifier
as well as Command Technologies and QRO amplifiers, judging from their ad
photos. So what determines whether shorting out toroidal turns in the PI-Net
will work or not?
Stan
WB6UYG
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