Relays usually are driven using optocouplers, which offer isolation between analog and digital grounds to ensure that switching currents in the relay coils do not affect the noise margin of the ...

Fig. 1: Add this relay to prevent shorted transistors in the MW-1. Usually after a transmitter is discontinued, any hope of upgrades or improvements fades. Some enterprising engineers can’t help but ...

An RC circuit in series with the coil allows full-current turn-on for reliable relay operation, then reduces the current to save power. Fellow engineer Sanjay R. Chendvankar of Mumbai, India, recently ...

How many remote controls do you have in your home? Don’t you wish all these things were better integrated somehow, or that you could add remote control functionality to a random device? It’s a common ...

As with many inventions, two people had the idea for an integrated circuit at almost the same time. Transistors had become commonplace in everything from radios to phones to computers, and now ...

The main principle of this circuit is that the door lock opens only when the buttons in series are pressed at a time. We can use it to lock the doors and for other security purposes. This article ...

The flip-flop, in whichever of its several forms you encounter it, is a staple of logic design. Any time that you need to ...