| 摘要 |
PURPOSE:To lower the grounding height of an antenna without deteriorating the irradiating efficiency by forming the antenna with a main pole having a function as a main conductor and whose base is grounded, and a sub conductor whose one end is folded by 1 1/2 to ground and expanded while being connected electrically to the top of the main pole and whose other end is connected to a feeding line supplying broadcast power near the ground. CONSTITUTION:A main pole 11 as a main conductor is made of a steel pipe, and the base 12 is fixed to an anchor 13 buried under ground and connected to a grounding plate 14 subjected to the 1st class earthing work. The main conductor formed by the main pole 11 and the sub conductor 17 form a grounding double folded antenna and inputs the broadcast power applied via a feeding line 28 to a terminal point of the sub conductor 17, that is, a feeding point 29. In expanding the grounding double folded antenna in a straight line, the current at the main pole 11 is larger than the sub conductor 17 in the current distribution of the broadcast power of broadcast power having a frequency 1MHz in the main pole 11 being the main conductor and the sub conductor 17. |
