A computer is very suitable for making (audio) measurements thanks to the sound card that is usually built in. Unfortunately, the audio input on laptops is usually too sensitive to measure s... Read more
Why build an electrosmog (‘E-smog’) detector? The answer is quite simple. More and more of our everyday objects are based on some sort of electrical ‘core’: your toothbrush, camera, cellphon... Read more
I’m in the process of building myself a single-ended class A MOSFET amplifier consisting of two monoblocks, and I don’t want to use a coupling capacitor between the amplifier and the speaker... Read more
This circuit clearly falls under the heading “Why didn’t I think of that earlier?” Virtually everyone who works with electronics has been faced with the need or desire to limit the inrush cu... Read more
These days there are many types of intelligent LEDs available. These LEDs flash or change their color, slowly or quickly and with different color combinations. Those LEDs that gradually chan... Read more
If you’ve read old textbooks on electronics basics you may recall how it’s possible to create a multivibrator from just a neon lamp and a capacitor. The circuit of the simple multivibrator s... Read more
To monitor the filling of a bath, a water tank, or a swimming pool, or to warn when a gully is overflowing, here’s a very simple water level detector built around a CD4011 CMOS quad Gates IC... Read more
LED Chase is a game that flashes one of eight LEDs randomly, the LEDs being arranged in a row. If the LED on the extreme right or left lights and the corresponding button (L or R) is pushed... Read more
Hall sensors can of course be purchased but making them yourself is far more interesting (and satisfying)! According to the theory the crucial thing is to use a touch layer that’s as thin as... Read more
The circuit described here provides monitoring of the charge status of a battery by the continuous measurement of charge and discharge currents. The battery current is integrated over time (... Read more
