Bias Calculator

Calculate Plate Dissipation Based On Plate Voltage And Cathode Current Readings. In these calculations, 5% of the cathode current is assumed to be screen current. This calculator is for a single tube.
Plate voltage DC voltage measured between plate and cathode. (Actual Plate Voltage) Example: Octal - pins 3 and 8 9 pin - pins 3 and 7	Cathode Current (milliamps) Displays Approximate Plate Current After Calculation	Plate Dissipation (Watts)
Note: For calculating plate dissipation in cathode biased circuits, subtract the measured cathode voltage from the measured plate voltage and use that as the plate voltage in the calculator above.

Calculate Plate Dissipation In Cathode Biased Output Stage Based On Voltage And Resistance Readings In these calculations, 5% of the cathode current is assumed to be screen current. With multiple tubes sharing the same cathode resistor, this calculator assumes the tubes are fairly well matched.
How many tubes share the same cathode resistor? (typically 1 to 4)	Voltage measured across cathode resistor	Actual resistance of cathode resistor	DC voltage measured between plate and cathode. (Actual Plate Voltage) Example: Octal - pins 3 and 8 9 pin - pins 3 and 7	Plate dissipation per tube (Watts)	Approximate plate current in each tube (in milliamps)	Will calculate and display plate power dissipation and approximate plate current per tube.