A roll-detecting sensor assembly includes a coil extending along and disposed about an axis. The coil comprises one or more portions, with each portion defining a winding angle. At least one of the portions defines a winding angle that is substantially nonzero relative to a line perpendicular to the axis, whereby the projected area of the coil in an applied magnetic field changes as the coil rotates about the axis. As a result, the coil is configured to produce a signal responsive to the magnetic field indicative of the roll of the sensor about the axis. In an embodiment, at least one of the portions defines a winding angle that is at least 2 degrees. In an embodiment, at least one of the portions defines a winding angle that is about 45 degrees.