A grill comprising a firebox assembly for mounting on a cart assembly, the cart assembly having first and second support assemblies interconnected by at least one linking member. The container comprises an enclosure having an internal volume and a base, wherein the volume is actively cooled using a refrigeration system or alternatively is insulated for retaining a plurality of freezable blocks or a quantity of ice therein. The feeding channel is surrounded by a pressurized chamber into which gas is fed and out of which gas is expelled from an opening. The transceiver front-end also comprises a first tunable capacitance connected between the transmitter node and the receiver node, and a second tunable capacitance connected between the signal transmission and reception arrangement node and a signal reference level. The present invention also pertains to electric current producing cells comprising such solid composite cathodes, and methods of making such solid composite cathodes and electric current producing cells. A piston spring connected to the piston is also includes and at least one secondary orifice.