If the battery is good, the LED flashes. This simple tester uses an LM3909 integrated circuit. We found this configuration in an old documentation.
This control circuit up to 1 kW was found in a 1967 RCA documentation. The components are from...
We found this circuit in an Analog Devices documentation from the 1990s. It provides an...
In this circuit the signal from the phototransistor is amplified by a Darlington stage and then...