A cold-plasma supply like the CTP-2000K has two different frequencies on two different timescales, and confusing them is the most common mistake. The fast carrier is the medium-frequency AC that actually drives the discharge — on the CTP-2000K a center frequency near 10 kHz, adjustable over roughly 5–20 kHz. On the modulated-pulse CTP-2000K/P a much slower burst envelope (about 1–1000 Hz) switches that carrier on and off, and the duty cycle is the fraction of the envelope that is on — not a slice of a single carrier cycle. Switch modes and watch the two scales.
Raising the carrier frequency packs more oscillations — and more chances for breakdown — into each second, tending to raise power and reactive-species output as well as gas heating. Burst modulation instead inserts off-time between bursts: the electrons de-energize almost instantly during the off-period while the gas keeps shedding heat, so a lower duty cycle lowers the time-averaged gas temperature. The CTP-2000K/P sets these independently; the microsecond-pulse CTP-2000KM adds separate pulse-width and repetition controls not shown here.