Low frequencies antennas can construct at low cost by using self-supporting iron towers as antennas. The authors had demonstrated it that a feed method with a folded line has high radiation efficiency in comparison to direct feed. In this report, consideration for details of antenna characteristics is conducted in simulation. Firstly, an effect of symmetrical feed method with multiple folded lines is shown. Next, the antenna using an iron tower is compared with an antenna using a metal mast which is a common constitution method. We clarify effectivity of the proposed antenna.