> He used a 60 watt light bulb in place of the non-inductive resistor
> and explains why it works even though the resistance changes as the
> bulb lights up with the following reasoning in his exact words:
>
> "At the time the bulb is brightest the load is the lightest (high
> resistance) but the amplifier input is in parallel with this and it is
> calling for more power. It is kind of self compensating."
What really happens is at the time when the grid is closest to
being overdriven or overdriven, the gain goes up. When the drive is
low with plenty of headroom, the drive power goes down more.
> He indicates that scope picture of amp output exactly duplicates
> driver alone.
Scope pictures are next to useless indicators of IMD performance.
Bad idea.
73, Tom W8JI
W8JI@contesting.com
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