Rich says:
>Can you accept what is on the constant-current curves?
Yes - but what has that got to do with it?
Quote again from Pappenfus et al. 'Most power tubes have a more linear plate
characteristic operating Class AB2, however.'
>I do not agree. Modern transceivers need a 50-j0 ohm load. With
grid
>current, the load Z on the exciter goes bananas
Not necessarily so. It depend on the relative ratio of grid swamping to non
linear grid current loading. Additionally, you appear to assume that the
input impedance of grounded cathode AB1 stage is constant and high. This is
not necessarily so - because of Miller effect.
If the driver has adequte NFB to reduce its output impedance, the effects
are minimised.
73
Peter G3RZP
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