Carl says,
>I never could get a straight answer why Ameritron uses a Pi-L on 80-160M.
Meeting the current FCC specs on harmonics with a pi network is at best
dubious. A Pi-L gives that bit extra. To meet the requirements of ITU(R)
Recommendation SM.329-7, which is supposed to be implemented for new
equipment from Oct 2003, and for all equipment from Oct 2012, even a Pi-L
will be dubious. (A class AB PA plate current has a second harmonic
component 6dB below the fundamental component). SM.329-7 requires harmonic
suppression of 43 + 10 log P dB without exceeding 50dB for equipment below
30MHz, and 43 + 10 log P not exceeding 70dB for equipment above 30MHz. So
far, the FCC haven't made any suggestion that they are going to implement
SM.329-7 in their rules. You would think that having accepted it at WRC97,
they would have gotten around to telling people that this change was going
to happen, but I guess it is because the international side doesn't talk to
the amateur side except on things that directly concern amateurs, and have
'amateur' stamped on them!
73
Peter G3RZP
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