This circuit can be implemented with either TTL or CMOS logic. The speed depends on the logic used and the circuit can be used with microcontrollers, functioning as a shield.
This circuit was published in an English magazine from 1980. The magazine no longer exists, but...
Found in a 1990s Motorola documentation, this high voltage circuit uses a PUT that is not a common...
This proximity sensor was found in a 90s Popular Electronics. The base is a PLL567 that operates...