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.
This old receiver (1967) uses germanium transistors from the time and coupling transformers,...
This circuit can act as a shield being controlled by a microcontroller by pin 1 or 2. The...
A negative pulse applied to the input of the circuit shown in figure bellow turns on the relay....