The quiescent dc conditions (bias voltages) are determined for a 'generic' amplifier configuration and by selecting very high or very low resistor values the basic configuration becomes a 'variable'. For instance the default value resistors will give the configuration and dc voltages of the shunt series circuit used in the FLEXI-BOX with HF Broadband Amplifier
This simulator is intended for linear calculations and can produce impossible results when the transistors are turned ON or OFF . These results are normally immediately obvious because they are negative or exceed the supply voltage. Some are more subtle and give results like a collector to emitter voltage of less than the transistor saturation voltage. There are indications of transistor conditions and the validity of the results but is up to the user to interpret the results as valid or not and also to allow for the effect of a variable configuration. The calculator has proven to be most useful, particularly when transistors with no spice data available are used, and is offered 'as is' with no guarantees.
W J Highton 8/4/2008
This calculator is provided free by Chemandy Electronics in order to promote the FLEXI-BOX
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