In one embodiment of the invention, a replaceable electrosurgical end effector cartridge is provided to couple to a mechanical wrist of a surgical instrument for a robotic surgical system. The condenser includes a water inlet and a water outlet for flowing water therethrough or proximate thereto, or is affixed to the tank or immersed into the tank to effect water heating without flowing water. An AC voltage signal is applied to the coil having first and second half-cycles. During operation of the disk drive the patterns are detected by the read head and interpreted within the disk drive using knowledge of the pseudo-random scrambling function, so that reading and writing of data can occur in the conventional manner. The pattern-generator cards contain pattern-generators that generate address, data, and control signals that exercise the memory modules.