Abstract: High speed automatic gain control (AGC) circuitry, capable of use in pulse or CW systems, incorporates hysteresis for improving the stability and distortion characteristics of the AGC. After a gain setting is selected, the built-in hysteresis feature prevents an adjustment in that gain setting until the amplitude of the input signal varies more than a predetermined amount. Sampling of the amplitude of the input signal and gain adjustments are accomplished by digital circuitry. In one embodiment, AGC is on a pulse-to-pulse basis.

Abstract: There is disclosed herein an upright vacuum cleaner comprising a main body having a suction opening, and a handle body pivotally attached to the main body. A lifting assembly for the main body comprises a pair of wheel assemblies pivotally attached to the handle body. These wheel assemblies support the vacuum cleaner in a manner to raise its suction opening and brush assembly from the floor when the vacuum cleaner is in its full upright or idle condition. The wheel assemblies are suitably attached to receptacles in the handle body to allow these assemblies to move out of the way when the vacuum cleaner is used in the normal cleaning fashion, but to engage the floor when the handle body is moved to the full upright position.

Abstract: The present invention discloses a second level bus arbitration method and apparatus for use with a distributed computer network. The invention alleviates any simultaneous access possibility by requiring any computing element which claims access to the bus to first send a pseudo-random sequence over a common line using open collector logic. A computing element can access the bus if the sequence appearing on the common line is the sequence it transmitted. The invented arbitration system does not require central control or centralized clocking.