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An induction thermal plasma system has been newly designed for advanced operation with a pulse modulated mode to control the plasma power in time domain and to create non-equilibrium effects such as fast quenching of the plasma to produce new functional materials in a high rate. The system consists of MOSFET power supply with a maximum power of 50 kW with a frequency of 450kHz, an induction plasma torch and a vacuum chamber. The pulse modulated plasma was successfully produced at a plasma power of 30 kW and a pressure of 760 torr, with taking the on and off time as 10 and 5 ms, respectively. Measurements were carried out on the time variation of the spectral lines emitted from Ar species. The plasma temperature in an on-off cycle was estimated by the Boltzmann plot method and it changed periodically from 0.5 to 2.5 e V during the cycle as well as deviated considerably from the estimation of thermal equilibrium calculation.