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.

Remote control receiver (CB21914E)
The frequency depends on the coil and is not found in the original documentation but should be...
Digital Do Nothing (CB26218E)
This is a device for those who need to show that they know how to use digital electronics but have...
Sinusoidal generator CA3130 (CB21987E)
Using an operational amplifier with FET, this circuit from a 1977 publication can generate...