| 摘要 |
<p>PURPOSE:To improve the reliability of a pulse modulator by providing a third winding induced to a primary winding and connecting a power absorbing means to absorb the power at a primary winding side through the third winding to the third winding when the pulse voltage induced to the third winding exceeds a prescribed value. CONSTITUTION:To a pulse transformer 16, a third winding TH having the approximately same winding as a primary winding P is connected in a polarity reverse to the primary winding P. To the hot end side of the third winding TH, the anode side of a power feed-back diode 19 is serially connected and the cathode side of the power feed-back diode 19 is connected to the plus side terminal of a power source 11. Consequently, when a positive voltage of the power source or above occurs, the power feed-back diode 19 is conducted, the current flows from the third winding TH to the power source 11 and the power is absorbed (charged) to the power source 11. Thus, the absolute value of the pulse voltage to occurring at the primary winding P and the third winding does not come to be a power source voltage or above and an abnormal voltage does not occur even at a secondary winding S side.</p> |
