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The time‐varying electric and magnetic fields inside a solenoidal coil have recently been calculated by Harmon. He modeled the coil by a cylindrical current sheet, used a physical approach starting from the Maxwell equations, and found results very different from what was believed from circuit theory since the 1920’s. Harmon’s derivation neglects the electric field‐current relation in the wire, i.e., it violates Ohm’s law. In this article, the fields are derived from the Maxwell equations with this omission amended. Instead of the current, the terminal voltage of the coil is taken as the independent input. The relation between the current and the electric field in the coil wire constitutes an additional boundary condition. It allows as additional variable an energy influx from the power source, whereas Harmon considered radiation from the coil outward only. With these modifications, the old circuit theory results are recovered again. Implications are outlined for the physical legitimacy of other models involving a given current sheet. © 1996 American Institute of Physics.