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Re: Homemade chokes



> 
>  This must be a new and different definition of Q which people have been
> tossing about lately.  The last time I checked, Q was defined (in my
> electronics texts at least) as the inductance (or capacitance in a cap)
> divided by the resistance!

Reactance/Resistance (not L or C directly).... 

Q is related to how much energy is lost in each cycle... 1/Q energy is lost
each cycle (why the ratio decrement and pi figures in....)  (think about it
as the voltage divided across the sum of reactance and resistance.  The
reactance is lossless, by definition, and the voltage across the resistance
is a loss)

It's also related to bandwidth and center frequency: Q  = Center
Frequency/(3dB bandwidth).. small bandwidth = high Q.   For a TC at 100
kHz, and a Q of 100, the bandwidth is a big 1 kHz..  High Q coils are hard
to tune for this reason.

and it's also related to the damping in a RLC circuit, if you write it as a
differential equation....


All different ways of saying the same thing...
>