There is a history of water conditioning using magnetic resonance (electromagnetic field) and radiofrequency since 1995 in the United States, Israel, Saudi Arabia and Mexico (Walter Savers Worldwide, 1997). The results indicate that Magnetic Water has altered thermodynamic parameters, stimulates plant growth, increases yields per unit area, reduces water consumption and keeps the tapes and drippers in the drip irrigation system clean (Bueno, 1997).

There are various patents that describe fairly simple electronic circuits (Binger, 1994; Hayakawa, 1995, Tamari, 1998). The magnitude of the magnetic field of the devices can easily be achieved with a market magnet (Noran et al., 1996, Romo & Pitts, 1998, Tamari, 1998). A surprising feature of the equipment is that its electrical consumption is always small or null. Therefore, "electromagnetic" devices for water treatment can be defined as truly sustainable equipment that produces an "electromagnetic" signal with low energy consumption and does not require chemical additives harmful to the environment.