Abstract: A phase-locked loop (PLL) circuit includes an input for receiving a timing reference signal, a phase detector circuit coupled to receive the timing reference signal, a controllable oscillator circuit controlled according to an output of the phase detector circuit, and a feedback divider circuit having an output coupled to the phase detector and an input coupled to the controllable oscillator circuit. The phase-locked loop circuit is coupled to output one of a plurality of output signals having an arbitrary frequency relationship to each other according to a frequency selection mechanism, the frequency selection mechanism including one or more input terminals coupled to control a divide ratio of the feedback divider circuit. The frequency selection mechanism selects one of a plurality of stored values.

Abstract: A patient support apparatus having a base, a litter frame, an elevation mechanism interconnecting the base to the litter frame and being configured to effect changes in elevation of the litter frame relative to the base. The litter frame includes a pair of laterally spaced and longitudinally extending support rails and a plurality of laterally extending support rails interconnecting the longitudinally extending support rails so that the litter frame has a rectangular configuration. Selected ones of the laterally extending support rails are mounted to the elevation mechanism.

Abstract: A phase-locked loop (PLL) circuit includes an input for receiving a timing reference signal, a phase detector circuit coupled to receive the timing reference signal, a controllable oscillator circuit controlled according to an output of the phase detector circuit, and a feedback divider circuit having an output coupled to the phase detector and an input coupled to the controllable oscillator circuit. The phase-locked loop circuit is coupled to output one of a plurality of output signals having an arbitrary frequency relationship to each other according to a frequency selection mechanism, the frequency selection mechanism including one or more input terminals coupled to control a divide ratio of the feedback divider circuit. The frequency selection mechanism selects one of a plurality of stored values.

Abstract: A patient support apparatus includes a base, a litter frame, and an elevation mechanism interconnecting the base to the litter frame and being configured to effect changes in elevation of the litter frame relative to the base. The elevation mechanism includes a pair of hydraulic actuators, each actuator covered by a telescoping shroud. The telescoping shroud is connected to the base and to the litter frame by a number of biased catches. The litter frame includes a pair of laterally spaced and longitudinally extending support rails and a plurality of laterally extending support rails interconnecting the longitudinally extending support rails so that the litter frame has a rectangular configuration. The litter frame includes a thigh section configured to be raised and lowered by use of one of a manually pumped hydraulic actuator or a gas-spring assisted lever actuator.

Abstract: A patient support apparatus having a base, a litter frame, an elevation mechanism interconnecting the base to the litter frame and being configured to effect changes in elevation of the litter frame relative to the base. The litter frame includes a pair of laterally spaced and longitudinally extending support rails and a plurality of laterally extending support rails interconnecting the longitudinally extending support rails so that the litter frame has a rectangular configuration. Selected ones of the laterally extending support rails are mounted to the elevation mechanism.

Abstract: Compressor system comprising (a) a first compressor having a first stage and a second stage wherein the first stage of the first compressor is adapted to compress a first gas and the second stage of the first compressor is adapted to compress a combination of a fourth gas and an intermediate compressed gas from the first stage of the first compressor; and (b) a second compressor having a first stage and a second stage wherein the first stage of the second compressor is adapted to compress a second gas and the second stage of the second compressor is adapted to compress a combination of a third gas and an intermediate compressed gas from the first stage of the second compressor. The first gas is at a first pressure, the second gas is at a second pressure higher than the first pressure, the third gas is at a third pressure higher than the second pressure, and the fourth gas is at a fourth pressure higher than the third pressure.