A method of organizing electron-wave interaction at the multiplied frequency of the signal wave is proposed.This type of electron-wave interaction provides multiplied-frequency electron bunching, which Womens hooded towel leads to formation of an intense harmonic of the electron current at a selected DL-Phenylalanine multiplied frequency of the signal wave.This effect is attractive for the use in klystron-type cyclotron masers with frequency multiplication as a way to increase the output frequency and improve the selectivity.