This bidirectional circuit was found in an American documentation from the 80's. The LEDs are common red, and the resistor is calculated according to the formulas next to the diagram.
The time the output is high (1) of a TLCSSB in the astable configuration depends on Ra and C. The...
The adjustment of the maximum load voltage is made in the trimpot. The circuit is from 1994...
This circuit from a 1967 documentation generates 2.5 Hz signals depending on the capacitors used,...