We found this circuit in a Japanese 1968’s documentation. The circuit makes use of transistors from that country common at the time of publication. Observe the symmetrical power supply for the circuit.
With this circuit, a relay can be activated from an alternating signal with frequency up to a few...
With this circuit the visually impaired can easily locate important places inside the house, such...
In the figure we have the way to use the transistors of an old-paired pair as a trigger circuit. The...