Diodes in DC circuits   Diodes in AC circuits   Half - wave rectiers with smoothing   Bridge rectiers with smoothing   Displaying diode characteristics on an oscilloscope   Light - emitting diodes   Photodiodes   Diode - like characteristics of transistor circuits   Input , output and control characteristics of transistors   Transistors in common emitter circuits   Transistors in common collector circuits   Transistors in common base circuits   Transistors used as switches   Transistors used as delay switches   Characteristics of eld eect transistors ( FETS )   FETS used as controllable resistors and switches   MOSFET characteristic   Dimmer sensor using a MOSFET   Characteristics of thyristors and triacs   Thyristors used as switches ·   Phase control using triacs and diacs   Characteristics of unijunction transistors ( UJTS )   Pulse emitter using a UJT