Testing Components Onboard and Offboard
I used to get this question either from my students or from ERG members about could all electronic components be tested onboard? I told them that as a beginner one must start to test the components off board so that they could understand the components characteristic. With this, they would know if a components is bad, leaky or good. Once they are good in testing electronic components off board, they then can slowly learn to test components on board.
I told them that NOT all components can be test on board. Components like coil, thermister, bridge rectifier, fuse, e-caps, transistor (with collector and emitter removed) can be test on board. Other components like the zener diode, diode, varistor, FET, non polar capacitor, resistors have to be test off board for accuracy reading.