The circuit presented was obtained in a technical documentation from National Instruments. The low-consumption circuit supplies a common LED with a voltage of just 1.5 V.
This simple alarm was found in a 1982 documentation, but uses components that are still common,...
Found in a 1969’s Electronic Design, this circuit operates in a narrow range of voltages....
This experimental circuit was found in a technical publication from 1976. The diode can be of...