Digital volume control circuit schematic
Controls & Timers
This is digital volume control circuit that Can be applied to the normal volume of a power amplifier. When press switch S1 adds up the volume and press switch S2 to reduce the volume down. How it works IC1 is a 555 CMOS Timer Single IC will be connected in astable flip-flop model as pulse frequency generator up / down to input pin of the counter IC2-74LS193, through push-bottom switch S1 (Up) and S2(Down). Changing wide of pulse signal from IC1 may replace R1 with potentiometer. To begin with, when we press the switch S1 (increase sound) binary output will …
High Temperature fire Alarm Circuit using transistors
Meters & Detectors
This is high temperature fire alarm circuit, when the temperature rise exceeds the limit, it will sound the siren rang out. It is easy to use with transistor circuit to detects heat. Then, a loud noise of the sirens with IC packages. How it works We uses the combination between Q1 (BC109), which is silicon NPN transistor and Q2 (AC188) which is PNP germanium transistor To detect heat in case of fire. Then, the siren will sound warning beeps. The collector lead of Q1 is connected with Base lead of Q2, while the collector lead of Q2 is connected with …