A Norton equivalent circuit is developed for a long-wire antenna used with a VHF man-pack FM radio exposed to an incident electromagnetic pulse (EMP). The required short-circuit current and antenna impedance are computed by use of a transmission-line model for the antenna, and the computations are compared with measurements of the short-circuit current and antenna impedance. The comparison shows that the transmission-line model for the antenna is adequate for performing a vulnerability analysis of the radio. A network model is developed for a portion of the radio and is used as the load in the Norton equivalent circuit. Load currents in response to an incident electromagnetic pulse from the Army EMP Simulator Operation (AESOP) are computed when the radio is tuned to specific frequencies in the low and high bands. The computed load currents are compared with experiment and show excellent agreement between theory and experiment.