We haven’t yet experienced this first-hand, but it seems to occur more often than when some websites are visited they switch the Internet connection over to a premium rate dial-up number. Th... Read more
The first circuit in Figure 1 shows a particularly simple LED flasher for AC power operation with six channels. All six LEDs flash entirely at random (not synchronized), producing a totally... Read more
Vehicle immobilizers are fitted as standard to modern cars and heavy goods vehicles. Antitheft mechanisms have become more sophisticated but so have the methods employed by crooks. Nowadays... Read more
If you like the emergence of visual patterns, be it natural or man-made, one you’re bound to be impressed by is the ‘synchronization’ of hundreds or thousands of fireflies. First, they flash... Read more
The big fear of every developer of a microcontroller or computer-driven control system is that the computer or controller could crash while it is in the middle of controlling something and t... Read more
When a lithium-ion battery is discharged below the minimum recommended cell voltage its life expectancy is dramatically reduced. The circuit described here can avoid this by disconnecting th... Read more
One of the most frequent uses of n-channel MOSFET’s is as a voltage controlled switch. To ensure that the MOSFET delivers the full supply voltage to the load it is necessary for the gate vol... Read more
The touch switch is based on a Schmitt trigger withhold contact. which is built from IC1a, IC1b, and R3. The output of IC1b is fed back to IC1a via R3. resulting in both gates maintaining th... Read more
With the aid of two D-type bistables contained in a 74HCT74 and some external components, any push-button switch can be used as a bounce free changeover switch. In the diagram, IC1b provides... Read more
The most obvious alarm indication is a flashing light.This requires relatively complex electronics. however, to achieve correct flash-ing. Moreover, in certain circumstances, such as when th... Read more
