Hans-Norbert Gerbig (12)

| 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...

| You switch it on and... ping! Or perhaps a gentle ‘pffft’ or just silence, but nothing more after that. Who hasn’t had this experience at so...

| 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...

| This simple six-component circuit flashes an LED to let you know that a fuse in some AC powered device has blown. Its operating principle is...