To begin with, Power ON Delay Circuit using IC 555 give time gap between power ON and circuit starts. When trigger comes, IC 555 work in monostable mode and give one output pulse for set time; furthermore, resistor R1 and capacitor C2 make timing part for delay. When the circuit is OFF, the output stays […]
DIY Projects
Panic Alarm Button Circuit using IC 555
Make cheap and easy Panic Alarm Button Circuit using IC 555, as this IC 555 work like bistable circuit with two states: alarm ON and alarm OFF. Pressing the panic button starts the timer, which stays ON until we press the reset button; the timer produces a HIGH output, turns ON the transistor, and activates […]
Light Detector Circuit using Wheatstone Bridge
An LDR changes its resistance when light falls on it and alight detector circuit uses this property in a Wheatstone bridge. One side of the bridge contains the LDR and a fixed resistor connected in series, while the other side contains a potentiometer and another fixed resistor connected in series. Furthermore, the circuit applies a […]
Frequency Divider Circuit
To begin with, a Frequency Divider Circuit take signal with high frequency and give signal with lower frequency, also it changes the signal in way to reduce frequency. Two common ICs used for this: IC 4017 Decade Counter: IC 555 Timer: Circuit Working: Parts List: Components Values Quantity Resistors (All resistors are 1/4 watt unless […]
Two-Way Intercom Circuit
This simple Two-Way Intercom Circuit let two places talk to each other like old home or office system; also main parts of this circuit are: Microphone: change voice to electric signal Audio amplifier (LM386): make mic signal strong Speaker: change strong signal back to sound SPDT switch: choose talk or listen mode Battery: give power […]
Long Range IR Transmitter Circuit
Compared to basic circuit this Long Range IR Transmitter Circuit can send IR light farther using easy parts, also its main idea is to make IR LED blink light in pulses. Furthermore, most IR receivers catch specific frequency made by IC 4047. Using more LEDs together or stronger LED gives more IR light, so with […]