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.

12 V power supply using a 6 V transformer (CB18705E)
This 12 V power supply can be made with scrap transformers from valve equipment that normally have...
LM386 Amplifier (CB4852E)
This is one of the many approaches we have on the site for this low power 0.5 W amp using the...
12V Battery Charger (CB12324E)
This circuit can be seen in several publications of the same time. The circuit is an application note...