Vesiniksagedusetalonis kasutataval vesiniku aatomil on kõrgeim energia, kui mõlemad spinnid on samasuunalised, ja madalam energia, kui need on vastassuunalised. Elektronispinni ümberpööramiseks vajalik energia vastab raadiosageduslikule footonile, mille sagedus on 1,420 405 751 768 GHz ja lainepikkus 21 cm ning mis on registreeritav vesiniku spektri joone abil.
The atom of the hydrogen frequency standard has a higher energy if both spins are aligned, and a lower energy if they are opposed. The amount of energy needed to reverse the spin of the electron is that of a radio-frequency photon with the frequency of 1,420 405 751 768 GHz and wavelength of 21 cm which is detected as a "line" of the hydrogen spectrum.
