> Rich says:
>
> >If the reactance of the inductor is equal to the reactance of the
> >capacitor, the L-network presents a short to the generator. What is the
> >impedance of a series-resonant circuit?
>
> Firstly, let's say it again. Resonance is where the input impedance of the
> network is resistive i.e. volts and amps are in phase. (There's another
> case where they are 180 out of phase, but that be neglected here)
>
> There are 4 varieties of L network.
>
> Series L, shunt C across the output.
>
> The effective shunt C is modified by the impedance of the load across it.
> It looks like an R and C in series. So it does not go to a short circuit.
>
> Series C, shunt L across the output.
>
> The L is modified by the load to look like L and R in series. never goes
> short circuit.
>
> Shunt C on the input, series L. Obviously can't go to a short circuit.
>
> Shunt L on the input, series C. Obviously can't go to a short circuit.
>
>
> Suggest you look at 'Electronic Applications of the Smith Chart' by Philip
> H. Smith. It's actually the best book I've found on Smith Charts, although
> the title sort of suggests that there are non electronic applications for
> it. Those I would love to see!
>
> Sorry Rich, we seem to have this total disconnect in that your definition
> of resonance and Q is different to everyone else's, and to that which
> electrical engineering generally accepts. Bit like the little old lady who
> went to see her grandson's passing out parade after he finished basic
> infantry training. 'He was ever so good' she said, 'he was the only one in
> step!'
>
>
> 73
>
> Peter G3RZP
The neat thing Peter is Rich extends his meaning of Q into his
special parasitic suppressors.
That's why Wes, N7WS, and Rich went into a cat fight.
Wes, who understands Q and complex circuits, measured
suppressors and said Rich's suppressor (and it wasn't even his
standard fair, it had more inductance and so LESS real Q than
normal) has negligible difference from a standard suppressor at
VHF but has a lot less Q at HF and lower.
I have to wonder how many people are duped into thinking things
are as Rich claims. I'm sure Rich believes what he says is true, he
just has his own definition of how things work.
73, Tom W8JI
w8ji@contesting.com
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