Transistor tester

These devices usually perform three types of checks: Some service testers include a go/no-go feature, indicating a pass when a certain hfe is exceeded.

Transistor hfe varies fairly widely with Ic, so measurements with the service type tester give readings that can differ quite a bit from the hfe in the transistor's real life application.

Hence these testers are useful, but can't be regarded as giving accurate real-life hfe values.

This type of tester is used for measuring transistor parameters dynamically under various operating conditions.

Among the important characteristics measured are: Transistor testers have the necessary controls and switches for making the proper voltage, current and signal settings.