[en] Harmonics of the ripple have been investigated experimentally at a self-made model Cockcroft-Walton (C-W) voltage multiplier, as a function of the circuit asymmetry and load. The results showed that the odd harmonics of the ripple was due to the circuit asymmetry and the even harmonics due to the charge-discharge process of capacitors. Under a light load condition, the fundamental harmonics was dominant compared with other harmonics, which could be considered to be the alternating ripple caused by the circuit asymmetry in the linear circuit approximation. When the circuit was asymmetrical, asymmetry of the diode conduction could increase the odd harmonics of the ripple