Abstract: An apparatus is provided to handle classes of data in computer systems that must not be permitted to intermingle due to their security classifications or criticality of their data content, as in banking or safety applications. An isolated path is established for transmitting a given class of data between elements of the computer system with assurance that the data has been transmitted from the proper source, has been received by an authorized recipient and that unauthorized elements of the system have not intercepted or altered the data. Plug in type secure bus arbiter (SBA) module or bus arbiter interconnect module (10) with a controller (11) provide a way to isolate data without modification of the computer back plane or motherboard in a computer chassis (12). Modules can be used with commercial off the shelf (COTS) and non-development item (NDI) cards for a wide variety of standard computer printed circuit boards.

Abstract: A radio receiver includes a blanker circuit for muting the receiver in response to interfering noise signals. The invention contemplates a transistor switch which, when biased to its nonconducting state, inhibits blanker action. The transistor is biased to nonconduction when the receiver provided automatic gain control (AGC) level is below the threshold voltage of the transistor. An adjustment is provided for controlling the AGC level at which blanker inhibit is introduced. Temperature compensating circuitry maintains inhibit action response at the threshold voltage with changes in ambient temperature.