Pulse generator with delay 555 (CB8922E)

We found this circuit in a Hands On Electronics from the 90s. The delay is given by the formulas next to the diagram.

Audio driver (CB7113E)
Found in a 1968 Mallory documentation, this circuit makes use of an integrated circuit of the...
Voltage multiplier 2 (CB9438E)
We found this circuit in an EDN from the 90s. The circuit is a voltage quadruplicator using...
Isolated zero-crossing switch (CB7419E)
This circuit was obtained in a General Electric documentation from the 80's, and can be used as a...