This circuit, found in 1993 documentation, is the traditional relaxation oscillator configuration with unijunction transistor. The frequency depends on C and the resistance value R.
This circuit, which can be used as a shield, was found in a 1980s documentation. The circuit can be...
This 555 timed touch switch was found in a 90s Hands-On Electronics. It triggers a buzzer, but a...
Found in documentation from the 90's, this circuit can be implemented based on modern operational...