This circuit is from Mullard 1969 documentation. The circuit operates at a relatively high supply voltage and has a 10 Vpp output. The transistors are of the time, but admit equivalents.
Found in old documentation, this circuit uses components that are still common on the market. The...
This circuit activates a relay by activating one of a series of optical sensors that can be...
We found this circuit in a 1996 publication. Equivalent components can be tried, especially in the...