This circuit, obtained from a 1965 magazine, can still be assembled using some modern equivalent components. The transistors may be BC558 and the transformer is obtained from a disused transistor radio.
This circuit can be used as an amplifier for musical instruments or even with your cell phone. The...
This circuit, which can act as a shield, was found in a 1970s American documentation. The...
This timer produces a continuous sound at the end of the timer set in potentiometer RV1. The...