A printer includes a system for cooling an image receiving member. By pressing a single button or key, a low-pass filter is switched into the signal path to filter voltage spikes, noise, and switching transients from pulse-width modulated pulses, or lower frequency sinusoidal signals with higher frequency components, and at the same time an on-screen icon indicates to a user that the filtered mode has been selected. An operator can use a configuration station to implement single or reoccurring queries that interact with the interface device and corresponding machines. The transmitter works to send out a predetermined radio wave. There is a water flow path between the inlet and the outlet. Exemplary embodiments and aspects include, without limitation, re-use of nuclear fission fuel, alternate fuels and fuel geometries, modular fuel cores, fast fluid cooling, variable burn-up, programmable nuclear thermostats, fast flux irradiation, temperature-driven surface areavolume ratio neutron absorption, low coolant temperature cores, refueling, and the like.