| 摘要 |
PURPOSE:To make the transmitter to have a protectively operating point having small dispersion by a method wherein the transformer at an electric power transmitting part is constituted of a material having the remarkable Curie temperature characteristic. CONSTITUTION:When an excessively large input signal is inputted to the input transformer 43, heat is generated according to the amount of loss. The calorific value thereof is designed as to be held at a sufficiently low temperature than the Curie temperature in the normally using condition. When the ferrite core material is heated to the Curie temperature or more by abnormal use, the material is changed immediately from ferromagnetism to paramagnetism, and AC initial permeability (muiac) is reduced abruptly. Accordingly the L value of the transformer 43 is reduced to fail in the duty as the transformer, the input signal is not transmitted to transistors 44, 45 at the final stage, and because the temperature is reduced automatically to some set fixed temperature or less, the transistors 44, 45 are prevented from thermal destruction. |
