An RF system includes a cryostat having a chamber and a cold region in the chamber, a high-temperature superconducting filter disposed in the cold area, a low-noise amplifier disposed in the chamber, a bypass switch coupling the high-temperature superconducting filter to the low-noise amplifier, and a conventional filter coupled to the bypass switch. The first application program is operative to indicate to the DAM program that a first data item processed by the first application program is available for further processing. Logic for testing a group of cells in parallel is disclosed. The obtained echo function is stored in a two-dimensional pattern whose first dimension is the burst frequency and whose second dimension is the time. A support member may be pivotally coupled to the footboard for movement between a stowed position and an extended position in which the support member may support the platform. A first rotor defines a cooling air inlet in its radially inward portion.