[en] By keeping only the essential physical effects the simplest possible quasilinear description of fast wave minority heating in a tokamak is presented in a tractable form suitable for convenient numerical implementation. The resulting quasilinear operator retains all trapped and passing particle effects and permits the minority heating resonance line to be offset from the magnetic axis. The quasilinear diffusion coefficient is shown to depend on pitch angle and inverse aspect ratio in rather different ways for a high and low field side off-axis resonance. Rather than averaging the infinite, homogeneous quasilinear operator, the derivation is carried out in tokamak geometry to properly treat the merging of distinct rf-particle interaction regions. Merging occurs when the banana tips of trapped particles are in the vicinity of the minority resonance, or, for both trapped and passing particles, when the minority resonance is tangent or nearly tangent to a flux surface. A smooth transition from distinct uncorrelated rf wave-particle interactions to the correlated rf interactions that occur at merging can be made by using a phenomenological collision model for gyrophase diffusion due to pitch angle scatter