Solid state relay (CB8518E)

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

500 Hz to 5 kHz Enhanced Oscillator (CB14913E)
In relation to the previous circuit (CB14912E) it has a control for the output signal strength. The...
LM741 Variable Gain Amplifier (CB25920E)
This circuit was found in a May 1981 Radio Electronics magazine article. The circuit is offset...
Halogen lamp protector (CB7865E)
Found in a 90s 303 Circuits, this circuit aims to provide a soft start for a low voltage halogen lamp....