>All the books on RF amplifier design

Indeed, "All" the books?

sorry, I don't mean to be nasty, I can't help it. Being a cellular engineer
at Motorola, I attended to infamous "Dale Carnegie" course that learned me
to "Never Criticize, Condemn or Complain" (hear no evil, see no evil, speak
no evil - go along and get along with social and management Pravda!) To "Not
pay too much" ("I'll give you something to cry about") to passively accept
and "not worry" - internalize, to blame oneself for ones stress related
illness and poisonings - (if you have a problem, your the problem). This
last technique of blaming the victim finds widespread application in abusive
families, police, prisons, communist brainwashing camps, and cult religions
that demand its members faith (and personal identities) are sinfull if their
faith will not heal their illness, if they must turn to science and doctors.
A very clever, subtle and insidius double bind that dumbs down and destroys
independance and initiative.

Of course, I got it all wrong, misunderstood what they were trying to
'teach' me. After all authority and social concensus is 'always right'. So I
don't need the 'double whammy' of getting smacked and ridiculed. Anyone hear
anything about the Motorola engineer Scott Falater that drowned his wife
while he was asleep? Or that Hewlet Packard woman that jumped from several
thousand feet out of the corporate jet?

I think corprate security has too many former CIA mindcontrol experts. But I
digress.

> say that class C RF amps should be operated with the transistor going
>fully between saturation and cutoff to maximize efficiency.

And harmonic generation too!

>What I don't understand, though, is this: when you
>design a transistor saturated switching circuit, you
>usually want to know the switching paramaters for the
>transistor (Ton, Toff, etc.) Yet, whenever I look up
>datasheets for RF power transistors intended for class
>C operation, no such parameters are given.
>What gives?

For RF transistors, have you found those funky things called "Smith chats"
that show the "Complex Impedance" vs Frequency?

> How are you supposed to know if a given
>transistor can handle class C operation at a given
>frequency?

You use a spice model and spice. Or you use the smith chart to tell you the
complex impedance, and design a conjugate matching network for the
transistor, input and output. The hybrid or S (scattering) parameters will
allow you to calculate the gain too, which the data sheets usualy provide
(Hfe, for instance).

Simply, the t-rise and fall are determined by the capacitive load the on the
transistor. Depending on the amplifier configuration (common emitter) , the
'Miller effect' can increase the effective capacitance. So your t-rise and
fall depend on frequency, external circuit components and amplifier
configuration.

ARRL has lots of good literature on design, which I will dig up references
for if no-one else tells you better. Seem to remember some old articles in
RF Design too. I wonder if their online?

> I'm also puzzled as to why you never see
>Shottkey-clamped transistors in class C RF amplifier
>service, since that would surely allow class C
>operation at higher frequencies, wouldn't it?

What? Putting a sharper pulse into the amplifier (with a diode 'clipper'?)
is done to generate harmonics. It would not improve the gain of the
transistor. But it is done with pulse sharpeners (frequency multipliers).

Scott

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The mob only rules what its members are allowed to achieve.

Is the American Identity defined in our Bill of Rights and Constitution,
or by corporate owned, politician bribing media concensus builders?
Quo Bono - Who Profits!
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