The circuit shown indicates voltages from 10 to 14 V used to monitor automotive voltage. One or two LEDs light up depending on the voltage.
Originally this circuit is from an English magazine, but I found it in Argentina's Radio Chassis...
This circuit was obtained in a 1967’s EEE. Transistors and integrated circuits can be replaced by...
In the figure we have a simple amplifier stage for BC547 series transistors. The gain is...