Abstract: A blood treatment system with pressure sensors may be configured to control blood flow to and from the patient and use readings of the pressure sensors to determine a change in a pressure drop across a flow restriction in the blood circuit to estimate a condition of the machine or the patient, or outputting data responsive to the estimation. Further embodiments employ measurement of pressure drop to detect abnormal viscosity or viscosity variations in order to detect possible infection.

Abstract: A method for protecting a circuit module in a communication device includes first detecting whether a circuit module is present in the communication device. A next step includes measuring a supply voltage to the communication device. A next step includes comparing the supply voltage to a predetermined threshold voltage. When the supply voltage is below the threshold, a next step includes supplying normal functionality to the phone and returning to the comparing step. However, when the supply voltage is above the threshold, a next step includes powering down a connection to the SIM card to limit functionality of the communication device.

Abstract: A multiple frequency band receiver (102) receives at least two frequency bands that are close but not adjacent. A first bandpass filter (304) passes signals in the first frequency band. A second bandpass filter (306) passes signals in the second frequency band. The first and second filters each attenuate signals between the first and second frequency band to at least a first level so as to provide selectivity in the frequency range between the first and second frequencies to prevent the signals between these frequency bands from being further processed by the communication device. A third filter (322) coupled to first and second filters passes signals in both the first and second frequency band and attenuates signals above the pass band of the higher of the first and second filters and below the lower of the first and second filters.

Abstract: An apparatus (304) for scanning among a plurality of channels in a radio communication system (300) includes receive circuitry (310) and control circuitry (312). The receive circuitry (310) is capable of being tuned to any one of the plurality of channels and measures reception strength of the tuned channel. The control circuitry (312) controls the receive circuitry (310) to scan through all of the plurality of channels one at a time. The control circuitry (312) stores a first reading of a measured reception strength of the tuned channel before powering off the receive circuitry (310). The control circuitry (312) stores a second reading of a measured reception strength of the tuned channel after powering the receive circuitry (310) back on.

Abstract: A receiver has a channel scan mode of operation and a communication mode of operation. In the channel mode of operation, the passband of a filter is narrowed relative to the passband of the filter in the communication mode. According to another aspect of the circuit, a local oscillator is selectively phase locked to an internal clock during channel scanning and locked to the incoming signal during a communication mode operation.

Abstract: A radio receiver, and associated method therefor, for generating a baseband signal having signal component portions of time-varying frequencies. The oscillating signal generated by at least one of the local oscillators of down-mixing circuitry of the receiver is modulated by a low-frequency signal thereby to cause the resultant, baseband signal to be comprised of signal component portions of time-varying frequencies. Because the signal component portions of the baseband signal are of time-varying frequencies, attenuation of such signal component portions and resultant distortion of the received signal, as a result of undesirable notches in the frequency response of a radio receiver is avoided.

Abstract: A radio frequency receiver (300) typically contains electronic devices commonly used in amplifying or mixing circuits (315) which are seldom ideal. The non-ideal characteristics of these devices lead to intermodulation (IM) distortion. A measurement of the amplitude of the received signal (301) is taken both unattenuated (503) and attenuated (507). The difference between the two measurements is compared (511) to predetermined limits (L1, L2 or L3) wherein the received signal (310) is determined to be valid, invalid or unsure. A valid received signal is demodulated in the receiver (300). An invalid signal, confirming the presence of IM distortion, is rejected. The unsure signal may be rejected or demodulated as determined by the receiver designer. This type of signal characterization is particularly useful for cellular radiotelephones (101) attempting to gain access to the system provider (111) in which it is registered.

Abstract: A battery charging system including a battery of one chemistry type and a battery charger for a different battery type is disclosed. If a battery over-discharge condition or if an electrochemical cell imbalance is detected within the battery, the battery prevents charging by the battery charger by means of a resettable switch.

Abstract: A rotatable contactless RF signal coupler, which couples RF signals between an antenna and an RF signal processor in a portable radio, along with an antenna capable of operating in two modes is described herein. Specifically, the signal coupler includes a transformer that is primarily located within the hinge formed by the housing of the radio and a rotatable flip portion. Substantially constant inductive coupling is maintained in the coupler regardless of rotation. The antenna is capable of operating in a narrow band and a wide band mode to afford antenna operation through varied conditions.

Abstract: An antenna for a portable cellular telephone includes a quarter-wavelength ground radiator and a helical coil capacitively coupled to an extendable half-wavelength radiator. The extendable half-wavelength radiator includes a metallic coil molded in plastic. The ground radiator includes a serpentined transmission line on a flexible circuit board. The helical coil and ground radiator are coupled by a transmission line to a duplexer. The duplexer couples transmitter signals from a radio transmitter to the antenna and receiver signals from the antenna to a radio receiver. The antenna may be advantageously utilized in any portable radio applications where small size and immunity to hand induced radiation losses are desired.

Abstract: Aromatic hydrocarbons are nitrated by reacting the aromatic hydrocarbon in a nitrogen tetroxide-containing liquid reaction medium, in the presence of a beta-dicarbonyl compound having a "W" configuration with a carbonyl group at each apex of the "W", preferably at a pressure and temperature sufficient to maintain the nitrogen tetroxide in the liquid state. Addition of an inert organic co-solvent to the liquid nitrogen tetroxide for the metal acetylacetonate promoted nitration of benzene essentially eliminates the production of dinitrobenzenes.

Abstract: Aromatic hydrocarbons are nitrated by reacting the aromatic hydrocarbon in a nitrogen tetroxide-containing liquid reaction medium, in the presence of a beta-dicarbonyl compound having a "W" configuration with a carbonyl group at each apex of the "W", such as a metal acetylacetonate, preferably at a pressure and temperature sufficient to maintain the nitrogen tetroxide in the liquid state. Addition of an inert organic co-solvent to the liquid nitrogen tetroxide for the metal acetylacetonate promoted nitration of benzene essentially eliminates the production of dinitrobenzenes.