Difficulties in the measurement of the couple coefficient for a compact Tesla transformer is solved using the method proposed by I. D. Smith. The couple coefficient was experimentally measured to be about 0.9, a little lower than the figure designed. The reasons for the decrease in the couple coefficient were presented. Electrical parameters of the Tesla transformer's circuits were estimated by experimental voltage waveforms, which is in good agreement with that from theoretical calculation. The Tesla transformer can meet the requirements of high-voltage charge to the forming line (FL).