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.

Drain dip oscillator (CB22029E)
This drain dip oscillator was found in an old English documentation. The JFET can be of any type...
SCS 5 kHz stages (CB9068E)
This SCS counter circuit was found in a 1964 General Electric documentation. The circuit has a...
MW Commercial Radio EB-180 (CB18352E)
This is the circuit of a commercial radio from the 60s, sold in Japan. The circuit shows the...