This circuit, which controls both the temperature and the level of a liquid in a reservoir, was found in an Electronic Design from the 90s. The circuit is based on a double 555.
The circuit shown in the figure consists of a low voltage dropout (LDO) regulator for 200 mA using...
Found in Radio Electronics from the 90s, this circuit has a power given by the output amplifier. The...
Many reed switches can be wired in series to perform na efficient alarm as shoen in the figure....