Rich...
Why do you find it so hard to comprehend that there's a FUNDAMENTAL
definition of "Q" from which all other "descriptions" or adaptations
descend?
It's in basic engineering texts going back at least 70 years. E.g.,
ELECTRONIC and RADIO ENGINEERING, Frederick Terman (Dean of the Stanford
School of Engineering), copyrighted first in 1932 and a classic at least
well into the 60's... p.45 under the general topic of "Resonance:"
Q = 2pi (energy stored in circuit) / (energy dissipated in circuit
during one cycle)
Eimac, as many others have pointed out previously, defined a parameter "Q"
for use in the flawed equations in their publications (and in many others
for decades), but that doesn't make either their equations or their
definition of Q anything but a peculiarity of historical interest which led
to a lot of badly designed low-Q matching networks and confusing results.
Terman is credible on "Q" and resonance. Various organizations,
publications and individuals who uncritically propagated one or more
inapplicable approximations to valid equations over the decades (and today)
are not. Time to do your homework.
Cheers,
Dick W0ID
-----Original Message-----
From: Rich Measures [SMTP:measures@vc.net]
Sent: Friday, August 06, 1999 2:17 AM
To: amps@contesting.com
Subject: RE: [AMPS] Pi-Net math
>
>I'm with you, Ian. Someone on this reflector very recently stated the
>basic, fundamental definition of "Q" as "(energy stored)/(energy
>dissipated)." I think "per cycle" is usually added. Ultimately that comes
>down to the very general form of X/R or R/X.
>
>Seems to me the fundamental fact Rich continues to ignore is that you
can't
>define a loaded Q, which is what we're inherently dealing with in matching
>networks, without including the dissipative element(s).
Eimac defines Q using RL. Q = RL/XC1. My contention is that with RL
and Ro connected to the Pi-network, the resonant frequency is neither
decreased nor increased.
.....
Rich...
R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures
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