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Old July 15th 03, 09:36 PM
Tdonaly
 
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Reg wrote,

Tom, sorry to be so disappointing. My Little formula for calculating L and
C for the constant resistance network is quite correct.


Yes, of course, but misleading because it implies that all four components
have to have the "same value in ohms (R)." In fact, the input resistance will
be the same no matter what the value of the reactive components as long as
they obey the requirement that L/C = R^2.


When designing constant-resistance networks it is convenient to have a
design-frequency.


Convenient, but not necessary to show that constant resistance networks exist.



It can be the frequency at which I said Xc = Xl = R ohms.


It can, indeed, or any other frequency for that matter.


So we can now calculate both L and C without prior knowledge of either of
them. After a little arithmetic it will be quite enlightening to discover ,
as you say, that L = C*R^2, but which is a less-convenient starting point.


Perfectly true, but what are you ultimately after?


In addition to a design frequency there can also be a design time constant.


Indeed.

---
Reg, G4FGQ


Tom Donaly, KA6RUH