[header] How to build antennas [title] Choose the rod length for your antenna. [step] You will need 2 rods that are 46.4 inches (117. 8 cm) long if you are designing the antenna to listen to non-commercial radio stations such as college channels. [substeps] You will need 2 rods that are 42.4 inches (107.5 cm) long if the antenna is for listening to fm band stations. 
[title] Place your rods perpendicular to each other and tie them together with a piece of string or tape. [step] You might need to tape together extra pieces to brace the frame.