This circuit was found in a 90s Wels' Think Tank. The frequency depends on C2 and R3. The handset or speaker must be at least 80-ohm. Observe the low supply voltage.
To obtain triangular signals, we have the circuit in the figure that uses two amplifiers. One of...
This circuit was found in an old Electronic Design. It makes use of sidacs and operational not very...
This circuit was found in an American publication from 1969. Transistors are from the time and can be...