W2VJN's book have this !
73 LA6FJA Rag
> From: John Lyles [email@example.com]
> Sent: 2010-03-30 05:28:24 MEST
> To: firstname.lastname@example.org
> Subject: [Amps] coaxial stub on amplifier output
> Has anyone seen anything in print about using a lambda/4 (Quarter
> wavelength) stub on the output of an amplifier with a tube. Its a nice
> way to bring water, tuning mechanisms into an output circuit, without
> looking like a short circuit for the primary frequency. This same stub
> is a half wavelength at second harmonic, so it reflects a short right
> across the output at F2. This should cause some plate current waveform
> modification, depending on where it is located physically with respect
> to the plate, i.e., similar to Tyler circuits.
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