This is the door bell circuit with flashing LEDs to make the circuit more attractive. IC1 (NE555) is applied right here as being a clock generator. It is actually set up as an astable multivibrator whose frequency could be altered using the support of potensiometer VR1. The clock pulses received from IC1 are fed to… Read More »
Here the variable desktop power supply which will convert a high input voltage (12V) from the SMPS / PSU of a desktop computer into small output voltage (1.25 to 9 volts). This converter will be very beneficial for electronics hobbyists. An adjustable three-pin voltage regulator chip LM317T (IC1) is applied right here to deliver the… Read More »
Here the circuit diagram of musical bell with touch switch and timer. This circuit is designed around CMOS IC CD4011 which work as the delay timer and IC UM66 which is well-known musical sound generator. When touch plates are bridged (touched) by hand for a moment, the circuit will start to produce music sound. Just… Read More »