Abstract: A radio communication system (100) has radio receivers (106) assigned to a predetermined one of a plurality of time periods (FRAME 0-127). The radio communication system (100) comprises a transmitter (104) that transmits information during the predetermined time period (FRAME 0-127) assigned to at least one radio receiver (106). A receiver (202, 206) receives information directed to said at least one radio receivers (106), the radio receivers (106) being individually assigned to receive information during at least one of a plurality of predetermined time periods (FRAME 0-127). A monitoring device (1702) monitors a level of traffic associated with each of the predetermined time periods (FRAME 0-127) and a measuring device (1704) measures a level of traffic associated with the at least one radio receiver (106) over the assigned predetermined time period (FRAME 0-127).

Abstract: An operational transconductance amplifier (38) is coupled to first and second supply voltages (41, 42) for converting differential input signals into a proportional output current. The operational transconductance amplifier (38) has a predetermined common mode input range, and a differential amplifier input stage (28, 29) having a non-inverting input (Vin+), and an inverting input (Vin-). The non-inverting and inverting inputs (Vin+, Vin-) receives differential input signals. Parallel connected transistors (36, 37) are coupled to the differential amplifier input stage (28, 29) for receiving the differential input signals. A current mirror (20-23) has first and second current paths, wherein the first current path sinks a common mode current from the differential amplifier stage, and wherein the second current path diverts the common mode current from the differential amplifier input stage (28, 29) in the event that the differential input signals fall below a predetermined magnitude.

Abstract: A class AB transconductance amplifier (200) has first and second differential input amplifier stages (100-112) adapted for receiving first and second differential input signals (Vin+, Vin-). First and second input cascode stages are coupled to the first and second differential input amplifier stages for providing first and second differential folded cascode signals. An output stage (113-118) is coupled to the first and second differential folded cascode signals providing an output signal indicative of a difference between the first and second differential input signals (Vin+, Vin-). A bias stage (101, 102) is coupled to said first and second differential input amplifier stages (103-104, 105-106) and the first and second input cascode stages bias the first and second differential input amplifier stages (100-112) to operate as a class AB folded cascode amplifier circuit (200). The bias stage generates class AB biasing signals.

Abstract: A simulcast system (FIG. 16) capable of synchronizing and maintaining synchronization of a plurality of base sites (1602, 1604, 1606, 1608) is coupled to a transmitter controller (226). The plurality of base sites (1602, 1604, 1606, 1608) is capable of transmitting data as radio frequency transmission at substantially the same time. A generator (1808) generates time marks (1708) at a predetermined time period (T). A data divider (1812) divides data into predetermined packets to be interposed between at least a pair of time marks. The data packets (1704) and time marks (1708) are transmitted to the plurality of base sites (1602, 1604, 1606, 1608). The plurality of base sites (1602, 1604, 1606, 1608) includes base site receivers (1603, 1605, 1607, 1607) for receiving the data packets (1704) and time marks (1708) and clocks (1611, 1613, 1615, 1617) for measuring the time (T) between each pair of time marks.

Abstract: A selective call receiver (111) has a first mask (134A) stored within the selective call receiver (111) indicative of a first period of reception for receiving a transmitted communication signal (99) having a plurality of packets (100). Each of the transmitted packet (100) has message information (110). An identifier (106) identifies the packet (100). The control signal (108) is representative of a second mask (134B) indicative of a second period of reception. The second mask is compared with the first mask for determining the second period of reception of the selective call receiver (111). A correspondence between the first and second masks determines whether to change the first period of reception of the selective call receiver (111) for receiving at least one additional packet.

Abstract: A connector (40) for insertion into a portable electronic device (30) provides testing, programming and power thereto. The portable electronic device (30) has a chassis (32) housed therein and further includes a battery cavity (35) with battery contacts (36) therein. The connector (40) has a distal end for contacting the chassis (32) through an access port (34) in the battery cavity (35). A proximal end of the connector (40) is adapted for connection to a cable. The connector (40) has a substrate (50) attached to a printed wire board (41), wherein the printed wire board (41) further comprises a first plurality of conductors (52) thereon for receiving data signals from the cable, and a second plurality of conductors (42) thereon for receiving power signals from the cable.

Abstract: A robotic placement device (FIG. 1) comprises a programmable end-effector (200) for picking and placing component parts. The programmable end-effector (200) comprises a cylinder (201) having a piston (202) including a first (203) and second (208) shafts coupled together. The first shaft (203) of the piston is larger than the second shaft (208). A controller (102) controls a pressure applied to the cylinder (201) and the piston (202) including the first (203) and second (208) shafts of the programmable end-effector (200) establishes a predetermined placement force at the programmable end-effector (200) while placing component parts. A control circuit 118 senses the pressure and in response thereto generates a signal. A processor 108 coupled to the controller (102) processes the signal and in response thereto varying the pressure for maintaining a substantially constant placement force at the programmable end-effector (200) while the programmable end-effector (200) moves vertically.

Abstract: A shock isolator (30) is provided within the housing (38) of a selective call receiver to substantially increase the natural frequency of vibration of the housing (38) and the printed circuit boards (54, 56) within the housing. The shock isolator (30) is a body of elastomeric material, preferably butyl rubber, which has component receiving apertures (32) molded therein for receiving the components (46, 48, 50) on the printed circuit board while at the same time contacting the printed circuit board. The butyl rubber has a damping of at least 25% (preferably 50%) and a Durometer of between 50 and 70 type A (preferably 60).

Abstract: A selective call receiver (100) including a receiver (102) for receiving messages and a housing (104) for housing the receiver (102). A clasp (200) for securing first and second wrist straps (112, 114) including a base member (202) and a pair of sides (204, 206) contiguous with the base member (202). A first compression member (208) located between the pair of sides (204, 206), the base member (202) and the first compression member (208) for engaging the first wrist strap (112) slidably therebetween. The first wrist strap (112) is also coupled to the housing (104). A clasp cover (214) having a second compression member (210) coupled thereto and to a first (204) of the pair of sides. The second compression member (210) engages the second wrist strap (114) with the first compression member (208) when the clasp cover (212) is transversely rotated between the pair of sides (204, 206) while the second wrist strap (114) also coupled to the housing (104).

Abstract: A selective call receiver (100) comprises a receiver (104) for receiving a message and a vibrator (116) capable of vibrating at a selected one of at least two selectable frequencies for alerting a user of a received message. The vibrator (116) also has a selector (120) or a tuning element (130) for varying the frequency of the vibrator (116).