Using the 741 this circuit can be adjusted to values between 1 Hz and 100 kHz. The power supply must be symmetrical. We found it in the Radio Electronics magazine of November 1973.
This circuit is from old European documentation. R1 depends on the output voltage of the...
This circuit can be used in an experimental link for educational purposes. based on an integrated 4093....
This circuit provides just over ½ W to a small speaker. We found this configuration in an old...