Wolfgang Zeiller (19)

| This small but very effective circuit protects a lead-acid battery (12-V solar battery or car battery) against overcharging by a solar modul...

| This design uses a classic two-transistor astable multivibrator configuration to drive the LEDs via a transformer from two standard 1.5 V al...

| With extended periods of bright sunshine and warm weather, even relatively large storage batteries in solar-power systems can become rather...

| We have featured numerous torch circuits using white LEDs. This simple design adds a couple of other types of LED to extend light emissions...

| Precision instruments for measuring temperature, altitude and light intensity have all appeared in Elektor Electronics, but those of us who...

| This secret lock, unlike a conventional code lock, gives away no hints to the unwanted visitor as to its existence: there are no buttons, sw...

| More and more electronic devices are portable and run off batteries. It is no surprise, then, that so many flat batteries find their way int...

| In this day and age when we’re surrounded by hi-tech we should leave it all behind and return to a very basic circuit. So stop thinking for...

| The voltage step-up converter described in this article is a transformerless design based on just one integrated circuit and a handful of...

| Button or coin cells that appear to be flat in their normal function may yet be discharged further. This is because in many cases, for i...