A steering control apparatus includes a first wire and a second wire extending from a distal end of a catheter to a steering assembly. The steering assembly includes a steering knob disposed at an exterior of the handle, a cylindrical steering shaft projecting from the steering knob and into the interior of the handle, a first cylindrical drum disposed within the handle and connected to the first wire, and a second cylindrical drum within the handle and connected to the second wire. The first drum is configured to engage the steering shaft to produce tension on the first wire. The first drum is coaxial with the steering shaft. The second drum is configured to engage the steering shaft to produce tension on the second wire. The second drum is coaxial with the steering shaft and axially adjacent to the first drum.