Rich:
The 3/2 power law is being used as a smoke screen and does not prove the
G2DAF, or any other amplifier that changes screen voltage as a result of
drive, will not work.
The 3/2 power law simply states that if you change all of the interelectrode
voltages applied to a power grid tube by a factor of 2, that the current
will change by a factor of 2.8.
In the G2DAF amplifier, the grid voltage and screen voltage vary in relation
to the drive, while the plate voltage remain constant. One unique feature
of the G2DAF circuit is that the ratio of grid to screen voltage varies
depending upon the drive as a result of the inefficiency of the half wave
doubler circuit. The more screen current that is drawn, the lower the
relative voltage applied to the screen.
The 3/2 power law is a simple conversion process for changing all of the
voltages on a screen grid power tube. It neither proves or disproves the
theory of the G2DAF design.
However, if you put a 2 mfd capacitor on the screen, overdrive the grid, use
a 4CX250 tube and yell into the mike as Norm did, then you can splatter.
Colin K7FM
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