Found in ancient American documentation this circuit uses semiconductors from the thyristor family such as SCRs, Triacs and unijunctions. The circuit can control loads up to 550 W with the indicated triacs.
Carbon microphones are no longer used in most projects. However, finding one in the scrap metal, it...
This circuit produces a strong tone of audio or ultrasound, depending on the values of components C1 and...
This alarm from an old 1978 publication uses PNP transistors and driver and output transformers that are...