| Never miss a blown fuse again! This ultra-simple four-component circuit ensures you’re instantly alerted when a mains fuse fails, using an a...
| Never miss a blown fuse again! This ultra-simple four-component circuit ensures you’re instantly alerted when a mains fuse fails, using an a...
| This handy transistor tester allows you to quickly test the function of an NPN/PNP transistor, JFET or (V)MOSFET and identify the correct le...
| Instead of converting a low frequency analogue signal to pulsewidth modulation (PWM) try using the signal to modulate a high-frequency oscil...
| Analog circuits have had their day; everything is digital now. Here we present a simple digital amplifier built with standard CMOS logic gat...
| Remarkably, in this transistor tester the TUT (transistor under test) flashes a bicolour LED. This allows you to see immediately whether the...
| Need to check fuses? A failed fuse indicator is a great solution, but it needs to be simple, affordable, reliable, and small. The straightfo...
| You can make a smart power bar (also called ‘block’; ‘strip’) with one single semiconductor component: a triac!
| The BF961 is a plain vanilla dual-gate MOSFET, which can also be configured to act as a Fetron. And with this Fetron you can build a simple...
| Tiny ultra-low power FM transmitters for testing VHF receivers are hardly rocket science. This design is notable, being easy on the pocket a...
| Small VHF receivers needn‘t employ complex FM demodulation circuitry nor be double superhets. Using a capacitive three-point oscillator in c...
