We found this circuit that converts a direct voltage into a proportional frequency signal. The circuit is from an Electronics Now from April 1993. The JFET can be of any type.
This circuit found on a William Sheets can be used with a headphone or external amplifier. The...
In the figure we have the circuit of a complete audio generator using the 741. The circuit was found...
This monostable multivibrator with signals in phase opposition was found in October 1986 Radio...