This Schmitt trigger was found in old documentation. The transistors can be of the general-purpose type like BC548 or even 2N2222.
This circuit, obtained from old documentation, doubles the frequency of the pulses applied to the...
The passage of an object in front of the LDR, producing a shadow or even turning off the ambient...
The CMOS TLC555 [equivalent to the bipolar 555] can be used as a monostable in the configuration...