Abstract: A transmitter, having controllable transmission functions is described for transmitting coded message signals to a plurality of portable communications receivers, the coded message signals including and message information interleaved with transmitter control signals synchornized with the message information. The transmitter includes a receiving section for receiving the coded message signals from an input source for transmission. A decoder which couples to the receiving section decodes the synchronized transmitter control signals to derive transmission control signals. A transmitter section, responsive to the transmission control signals, transmits the coded message signals. Additional transmission control signals may also be derived from one or more receiver control signals embedded in the coded message signals.

Abstract: A modular building block for electronic circuitry is provided with areas for mounting circuitry thereon. Posts of a particular geometric shape and receptacles of a complementary geometric shape are provided on the substrate. The posts and receptacles are coated with an electrically conductive material and connected to nodes within the circuit such that when blocks are interconnected, post within receptacle, the interconnection provides both physical and electrical connection. An alternate embodiment is disclosed having fingers and edge cards, configured such that the fingers of one block grasp the edge cards of another block, providing physical and electrical connection between the blocks.

Abstract: A battery saving apparatus for supplying power to a selective call communication receiver for enabling the detection of a synchronization codeword in data received in a predetermined signaling format comprises circuits for supplying power to the receiver, and for detecting valid data received during a first portion of the first predetermined time interval. Power is maintained to the receiver for the remainder of the first predetermined time interval when valid data is detected in the first portion. A synchronization codeword detector is included for detecting a synchronization codeword. When valid data is subsequently detected following a second portion of the first predetermined time interval and the synchronization codeword is not detected in the first predetermined time interval, power is maintained to the receiver for a second predetermined time interval to further enable detection of the synchronization codeword.

Abstract: A paging receiver having acknowledge back capability is provided with the capability to request a received message to be forwarded to an alternate paging receiver in a paging system after having received its address and associated message. The paging receiver includes an entry device for selecting the alternate paging receiver to which the message is further to be sent, and after the selection is made, the paging receiver generates the acknowledge back response requesting the message be further sent to the selected alternate paging receiver.

Abstract: Apparatus and method is disclosed for storing and subsequently transmitting later messages for system pagers with acknowledge back capability that nevertheless fail to acknowledge back in the first instance. Addresses are retransmitted for pagers initially failing to acknowledge back on a continuous periodic basis until such acknowledge back is received, at which time the message intended therefor is sent, or a predetermined time period expires.

Abstract: An encryption key, required to encrypt and decrypt data according to a predefined algorithm is usually retained in a volatile memory device. Detection of loss of the key or corruption of the key is frequently possible only be means of the encryption circuit itself testing the key. Automated and repetitive testing of encryption keys by means of a processor or a control circuit periodically requesting the encryption circuit to test an encryption key minimizes data loss and system down time due to corrupted or lost keys.

Abstract: Ceramic dielectric substrates, calcium titanate, bismuth titanate and strontium titanate, used with superconductor, Ytrium Barium Copper Oxide, or YBC, as an electrode, produce a superconducting electrical device, useable as a filter or capacitor. The electrical device formed by using one of the dielectrics taught herein in combination with YBC, is mechanically stable in comparison to prior art ceramic dielectrics that used YBC for an electrode material, in that the YBC is substantially free of microcracks and remains bonded to the substrates.

Abstract: A virtual ground memory which has four state cells coupled to bit lines has a load directly connected to each bit line to reduce the degradation of the output of a selected memory cell due to voltage drop caused by current flow between load and selected memory cell. Additionally, loads which are coupled to the bit lines are also coupled to an adjacent virtual ground line to avoid providing a separate power supply line for the loads.

Abstract: A CMOS Schmitt trigger which has two series-connected inverters uses both an input and an output signal to provide hysteresis. A pair of series-coupled transistors is coupled between a power supply terminal and a node between the two inverters. One of the transistors has a control electrode for receiving the input signal. The other of the transistors has a control electrode for receiving the output signal.