Integrated signal generator appeared in Radio Electronics magazine in January 1968. The integrated circuits are from the time and the generator produces signals from 5 Hz to 50 kHz.
We found this circuit in an American 1980s documentation. The operational ones used are not common...
This filter with the 741 op amp was found in the February 1995 Electronics Now magazine. The power...
With two cascading tunnel diodes, this circuit found in a 196 General Electric documentation...