Found in American documentation from the 90s, this circuit uses a high voltage relay and has no grid isolation. The high values of R1 and R2 prevent the shock when it touches the sensors.
Obtained from a 1980s Linear Technology documentation, this circuit has a hysteresis of less than...
Found in documentation from the 1980s, this circuit makes use of discrete components of the time....
With this 1-transistor circuit we have a high input impedance and good gain. The circuit is from a...