This circuit was obtained from a 1947 amplifier manual. The circuit makes use of a transformer source, but it can also be battery powered.
This circuit produces a sine 1 kHz signal. The frequency is given by C1, C2 and C3. This is a...
This circuit is a traditional configuration with the 741 Operational Amplifier and its gain is...
We find this vibrato configuration with transistors in a 1987 documentation. The components are still...