We found this circuit in a 1968 Electronics World. The circuit uses a transistor of the time providing a 16 dB signal gain with a 4 V output.
Two operational are used on this triangular-rectangular oscillator suggested by Motorola in its...
This circuit from a Popular Electronics from the 90's can generate signals from 0.03 Hz to 3 kHz...
With 8 to 30 V power supply, the output power depends on both the voltage and the load. The...