This automatic brightness control that uses an LDR as a sensor, was found in American documentation from the 1980s. Resistors in series with LEDs depend on the desired current.
Found in Electronics now, this circuit generates signals given by the formulas next to the...
This source was found in the National Semiconductor's Linear Applications Handbook of 1994....
This circuit is another practical idea for places where they still receive signals from analog TV. The...