16.6 UNIJUNCTION TRANSISTORS
A unijunction transistor as discussed in chapter-12 exhibits a V–I characteristic as shown in Fig. 16.28. The device is ON when v = VP and OFF when v = VV. The device is used as a switch.
16.6.1 An Astable Multivibrator Using a UJT
The Fig. 16.29(a) gives an astable multivibrator using an UJT. Let initially the diode D be ON. Then its forward resistance is small. Thevenizing the circuit at E,
Initially, when the UJT is OFF, the capacitor tries to charge ...