Vacuum-Tube Input Admittance

The input load of a common-cathode vacuum-tube amplifier can be specified as impedance or admittance. If specified as admittance, it is defined as the current flowing into the control-grid divided by the voltage applied between the control-grid and the cathode. An equivalent admittance circuit is a capacitor shunted by conductance. An equivalent impedance circuit is a capacitor shunted by resistance. ©2004 Martek International All rights reserved.

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