Semiautomatic Transistor Characteristic-Curve Plotter

A simple semiautomatic instrument for tracing common-emitter hybrid collector and base characteristics of low-level transistors is described. DC supplies, including a transistorized automatic and continuously varying voltage supply, are encountered in the network which allows appropriate biasing of transistors to be tested. Plotting of transistor curves is provided by a conventional X-Y recorder. The range of the instrument comprises: for plotting collector characteristics-base currents up to 40 μa, collector voltages up to 15 v; for base characteristics-base currents up to about 30 μa. The instrument enables accurate and rapid plotting of transistor characteristics, which is of considerable importance for special design purposes, when trade data of transistors prove to be inadequate.