The most simple example of a constant-resistance network is a capacitor
in
series with a resistor, both in parallel with an inductor in series with
a
resistor. When all 4 components have the same value in ohms (R) then the
input resistance is a constant resistance R from DC to infinity.
----
Reg, G4FGQ
Since the reactive components change reactance with frequency, Reg's
network
may be a little hard to realize in practice. Try making the inductance
equal
to
R^2*C Reg. You might have better luck. You also might want to review
Everitt's
take on this subject, starting on page 284 of the second edition of his
book,
_Communication Engineering_. His ideas are quite enlightening.
73,
Tom Donaly, KA6RUH
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Tom, sorry to be so disappointing. My Little formula for calculating L and
C for the constant resistance network is quite correct.
When designing constant-resistance networks it is convenient to have a
design-frequency.
It can be the frequency at which I said Xc = Xl = R ohms.
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.
In addition to a design frequency there can also be a design time constant.
---
Reg, G4FGQ
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