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Old September 1st 03, 09:24 PM
Kevin Aylward
 
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Don Pearce wrote:
On Mon, 1 Sep 2003 16:02:24 +0100, "Kevin Aylward"
wrote:

Don Pearce wrote:
On Mon, 01 Sep 2003 14:16:51 +0100, Paul Burridge
wrote:


Is a tuned load (tank circuit) a viable load for an RF amplifier
operating in class A? Or is this type of load only really suitable
for class C?

Of course you can use a tuned load with class A. But the nice thing
about a tuned load is that you don't *have* to use class A to
achieve a clean output. Of course, if you are using an amplitude
modulated signal, then you will need class A.


That is, if the input signal is already AM, you need a class A or
linear amplifier. If the AM is to be done at that stage itself, then
its the class c non-linear bit that makes the multiplication
modulation work.

True - I was considering only the "carrying the signal" case. Anode
modulation of a PA is a different matter.


Yes, I know you knew, I was just tiding up the description a bit for
others.

Kevin Aylward

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