Discussing coupled impedance in a double tuned circuit...?

Thread Starter


Joined Apr 3, 2015
Hi friends,

In a double tuned circuit at resonance the coupled impedance transferred from secondary circuit is pure resistive which increases the primary resistance causing primary current to decrease which result fall in secondary current causing the output to decrease whereas as at non resonant frequencies i.e high and low frequencies the coupled impedance is reactive which cancels the reactive impedance already present in the primary circuit which nullifies the primary impedance causing a flow of large current in the primary. This result in a double hump curve as shown..

What I want to know is that resistance R is a static quantity independent of operational frequency then why at non resonant frequencies R is not coupled along with reactive impedance...??

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