The author found that a long-neglected gel battery in a hand-held vacuum cleaner had gone high-resistance. It took some effort to make it usable again, by alternately applying voltages of op... Read more
Elektor is all over the globe, starting out from Holland. The same with bicycles, which are even older. All the way from Åland Islands N60 E20 (check that out), Anders Gustafsson wrote 2 us:... Read more
When testing circuits and fault finding there is often a need to inject a defined DC voltage level at some point on the circuit. It may, for example, be necessary to apply a logic level on t... 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
Some microcontroller applications such as those which log or track information often require current time and date information to be stored along with the collected data. A Real Time Clock (... Read more
This small circuit was developed to monitor the battery in a model hovercraft. The lift in the model is produced by an electric motor driving a fan. To avoid the possibility of discharging t... Read more
The circuit described here lets you control a cellar drainage pump so that it turns on when a preset liquid level is reached and turns off again when a different preset level is reached. The... Read more
Simple mechanical timers, which you can buy for a couple of pounds in every home improvement center, are suitable for switching something on and off one or more times per day. They can be us... Read more
Like all its counterparts, this network wiring tester comprises two elements, a transmitter unit, powered and fitted at the network start point, and a receiver unit, passive, which can be mo... Read more
Here are two circuits that make it possible to add up to eight detectors to an existing alarm system without running a single cable. Each transmitter has a unique number that is reported to... Read more
