A transistor tester can be a handy addition to your electronics workbench. This versatile transistor tester design, first presented a decade ago, enables you to quickly assess the functionality of NPN ...

Signals when an on-circuit battery is exhausted, 5V to 12V operating voltage A Battery-status Indicator circuit can be useful, mainly to monitor portable Test-gear instruments and similar devices. LED ...

In the modern world, we use batteries in almost every electronic gadget from your handheld mobile phone, digital thermometer, smartwatch to Electric Vehicles, aeroplanes, satellites, and even Robotic ...

This circuit, designed on request, has proven to be useful to indicate when the voltage in a power supply line is changing from 120V to 240Vac. It can be used in different circumstances and circuits, ...

If you’re working with 3.3V or 5V circuits, it’s easy for you to throw on a power or status LED here or there. [Tom Gralewicz] has found himself in a pickle, though, often working on projects with ...

The following circuit uses a low-power CMOS comparator and an LED to indicate low-battery voltage without causing excessive current drain. To view the application note, click on the URL below. Circuit ...

LED VU meters are popular devices, especially for those people who love music. With this device, you can easily look at the level of sound with a glance at the LEDs. if you are thinking about making ...

ABLIC has launched the S-82F9 Series for driving five LED indicators and the S-82D9 Series for driving four LED indicators, both of which are designed for voltage monitoring ICs to provide simple ...

Back in 1977, for most people, if you weren’t home to hear a ringing phone, the moment was gone forever. Unless, that is, you built Elektor’s ingenious "Telephone Tell-Tale" missed-call indicator.