At 2:12 PM -0500 2001/1/28, measures wrote:
>...All one has to do to run class A is reduce the mic.
>gain until anode current does not increase during modulation.
True but incomplete, therefore confusing or misleading. If you want to get
much power out of your amp you must reduce the negative grid bias (or
perhaps with some tubes bias the grid slightly positive) to increase the
quiescent anode current so that decreasing-current peaks are not clipped at
all. You must limit dissipation to a safe level, of course. Most "linear"
high-power amps are normally biased for Class AB operation, in which plate
current cuts off during decreasing-current peaks.
-Chuck W1HIS
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