The frequency of each note depends on R2, which must be replaced by a keyboard. The circuit is from Radio Electronics from April 1980. The power supply is 9 V for the amplifier used.
We found this circuit in a documentation on active filters from 1977. The gain of this circuit is...
The touch sensor of this circuit consists of a single plate that must be touched to obtain an...
The integrated circuit used in this project is not common today, as it was obtained in the Linear...