This circuit goes into operation producing a sound on a small speaker when the supply voltage drops below the zener voltage. The circuit operates with voltages in the range of 9 to 15 V. The unijunction transistor can be 2N2646.
This circuit goes into operation producing a sound on a small speaker when the supply voltage drops below the zener voltage. The circuit operates with voltages in the range of 9 to 15 V. The unijunction transistor can be 2N2646.
