We have many versions of biofeedback with the 555 IC on this site. This is another one. We found it in October 1986 Radio Radio Electronics magazine. The power supply must be isolated.
We found this circuit in a circuit manual from the 1980s. The circuit eliminates the conductive...
This circuit generates interval signals controlled by a light sensor. The basic time of the sound...
This high-gain digital amplifier uses general-purpose transistors. The supply voltage is logic...