Analog Electronics with LabVIEW®

C.4. Accuracy of Transistor Gain Measurements

We want now to consider the measurement of the gain of the transistor amplifier (Fig. C.1) based on the linear model. This model is not valid if the signals are too large, such as to cause an unacceptable degree of nonlinearity. If the linear model is valid, the signal input voltage magnitude, between the base and emitter of the transistor, is related to the fraction I_c/I_C according to [combining (C.7) and (C.12)]

Equation C.24

This voltage must be large enough for a good measurement using the DAQ board in the computer (i.e., at least a few millivolts), yet small enough so as not to cause substantial ...