If the battery is good, the LED flashes. This simple tester uses an LM3909 integrated circuit. We found this configuration in an old documentation.
We found this circuit in a Electronics Hobbyst from 1977. The circuit is indicated to adapt the...
June 2017 - These new AVX capacitors are suitable for filter applications, considerably reducing...
This powerful pushbutton uses a power MOSFET. We found it in a Popular Electronics magazine from...