Integrator with bias compensation (CB20991E)

This circuit was found in a Popular Electronics from the 90's. It can be implemented with equivalent operational amplifiers.

Mini Flasher (CB4416E)
This conventional slow-moving circuit uses incandescent light bulbs, but can be changed to use...
Electronic Dice (CB12221E)
This TTL dice is from an old publication from 1978, but it can still be assembled, as the...
Gate Control (CB18152E)
The purpose of this circuit is to control magnetic door locks activated by the power grid. The...