An analytic expression of electromagnetic near field emitted by a single current flow along a straight wire is derived to obtain the radiated EMI limit from the telecommunication lines connected to the equipment. The validity of the theory is tested in the experiment. Calculations show that the conversion factor between the electric field strength and the terminal voltage is not significantly changed by the wire length. A maximum conversion factor of about - 30 dB in the frequency range of 0.1- 30 MHz is obtained
