This simple circuit, found in American documentation, uses only one relay that locks when any of the sensors is activated. To reset, simply turn off the power for a moment.
Found in American documentation from the 1970s, this circuit is intended for amplifying analog TV...
This circuit uses only passive components and the instrument can be a microammeter or the lowest...
This oscillator generates quadrature signals, that is, with a 90-degree lag. The frequency is...