Most people have at least seen those cheap component testers you can buy on the Chinese websites for $10 or so. If you haven’t seen them before, they usually have some kind of multi pin socket. You ...

This tester is primarily meant to test bipolar transistors. It can indicate the type of the transistor as well as identify its base, collector and emitter pins. The circuit is very simple. The ...

This tester is intended to quickly check whether a transistor is functional or not and possibly also select two or more transistors with (approximately) equal gains. This is about the simplest ...