One of the tools available for engineers to use, if it is determined the oscillator might be causing a problem, is a spread spectrum oscillator. Spread spectrum is a technology used to reduce the peak levels of EMI emitted by the equipment by spreading the spectrum of the oscillator, instead of sending all of its energy to one fundamental frequency. As the graph here shows, with spread spectrum the energy is reduced, as opposed to not having a spread spectrum oscillator. Modulating the oscillating frequency leads to spread spectrum. In this example, the engineer is using a Hershey-kiss modulation profile with 25.4kHz frequency.