close
close
close
Home Tags Ece projects

Tag: ece projects

This circuit gives audio-visual indication of the failure and resumption of mains power. The circuit is built around dual timer IC LM556. When mains is present the bicolour LED glows in green colour, and when mains fails it turns...
Hide this solar-powered circuit suitably and see the reaction of your friends to the chirpy sound produced by it every few minutes. In all probability, it will coax them to find out where the sound is coming from. The circuit...
Certain industrial controls require accurate switching operations. For example, in case of a foot-switch for precise drilling work, even a small error in switching may cause considerable loss. This low-cost but accurate foot-operated switch can prevent that. IC NE555 is...
Many a times equipment at workstations remain switched on unnoticed. In this situation, these may get damaged due to overheating. Here is an add-on device for the workbench power supply that reminds you of the power-on status of the...
Need to connect more than one audio-video (AV) source to your colour television? Don’t worry, here’s an AV input expander for your TV. It is inexpensive and easy to construct. The working of the circuit is simple and straightforward. Whenever...
Nowadays, high-power light-emitting diodes (LEDs) LXHLMW1C are available in the market. These white LEDs contain indium-gallium-nitrogen (InGaN). The LEDs’ emitting capacity is 20 candela (Cd). We can use these LEDs for automatic garden lighting and wide voltage operation by...
Small-size AA cells and button cells used in electronic devices providing a terminal voltage of 1.5V are normally rated at 500 mAh. As the cells discharge, their internal impedance increases to form a potential divider along with the load...
This add-on circuit automatically turns on your porchlight when your doorbell rings, so you can see the person ringing the doorbell at the doorstep. This also helps to guard against burglars, who usually press the doorbell switch to confirm...
Here’s a low-cost two-way intercom circuit with musical ringtone that can be made using readily available components (see Fig. 1). Melody generator IC UM66 (IC1) generates ringtone for the intercom circuit. The supply voltage to IC1 is limited to 3.3...
Very often we forget to switch off the peripherals like monitor, scanner, and printer while switching off our PC. The problem is that there are separate power switches to turn the peripherals off. Normally, the peripherals are connected to...