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.
Standing wave ratio or SWR is an important measure of whether all power from a transmitter is being...
This circuit is from 1976 Radio Shack documentation. It detects when rapid variations in the light...
This circuit was found in an Electronics Now of the 90s. It is intended for amplifying composite...