Solid state relay (CB8518E)

This circuit was found in a 90s Popular Electronics. Both the coupler and the MOSFET can be of any type.

Biestable photo (CB8336E)
This circuit was found in 1967 Philips documentation. It uses transistors from that time....
Sequencer for Relay Control Using the 4017 (CB503)
Output stages driving relays or other loads are plugged to the outputs of a 4017. The trigger...
Earphone Amplifier (CB416)
This is a amplifier for XTAL high impedance earphones or piezoelectric types. Current drain is...