Soft x-ray emission from the Oak Ridge Tokamak (ORMAK) has been studied with an array of diode detectors. The thermal character of the plasma emission allows observation of phenomena associated with fluctuations in electron temperature. Measurements of internal disruption growth rates and repetition times corroborate a theoretical tearing-mode instability model. Heat pulses from the disruption evolve diffusively, but with a heat conduction coefficient larger than that inferred from the plasma equilibrium.