R: [AMPS] L-Pi net...downside?

[Peter Chadwick]

Rich says:

	>?  When an L-network is resonant, it is a dead short, Peter. 

Rubbish. Twaddle. WRONG!!! Do the mathematics of series parallel transforms.

	>?  The Eimac definition of R/XC1 is one.  The other definition of Q
is a 
	>lot more complicated and gives a different result.  I use Eimac Q.
I am 
	>lazy.  

That's an approximation that applies only to the complete network and falls
over at low values of Q. It may be one you can get away with - it doesn't
mean that it's right.

	>> Further, you have not yet given a rigorous definition of
resonance
	>>capable of  being modelled mathematically. 

	>?  equal and opposite reactance - - which does not mysteriously
>disappear whenever a dipmeter is brought near.    

Only applicable to very simple circuits, and the 'resonant' frequency that
it gives is not the resonant frequency that we want - which is where the
correct non reactive load is presented to the PA tube.

>?  The advantage of the dipmeter is that it obviates prestidigitations.  

Reinforces misconceptions about technical matters

cheers, Rich

73

Peter G3RZP


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