Controlled oscillator system with a time dependent output frequency

A controlled oscillator system is presented for providing an output with a frequency which changes with respect to time and with a phase which is within established phase error limits. The system includes a frequency synthesizer with a symmetrical search oscillator, capable of tuning the output with a range of + or - 100 Hz about any fixed frequency to which the synthesizer is set. For a tuning range of 200 Hz (+ or - 100 Hz) an expanded search oscillator output of a frequency range of 4 MHz (from 1 MHz to 5 MHz) is provided. A counter counts continuously the expanded output cycles and at each of fixed sampling intervals, for every 0.1 second, the count or number accumulated in the counter is read out. The sample number is compared with a theoretical number which should be present in the counter at the particular sampling instant for proper synthesizer's output frequency and phase

Digital-to-analog converter operates from low level inputs

Circuit controls a voltage controlled oscillator from computer output binary data representing a rate at which the oscillator is to change. It operates with low level output devices such as integrated circuit registers and devices with somewhat variable output levels

Minicomputer-controlled frequency generator

Extremely-accurate and low-phase-noise frequency generator varies oscillator frequency as predetermined function of time. System could be used: (a) to automatically vary transmission frequencies in accordance with seasonal and diurnal changes in ionospheric conditions, (b) as automatic tuner for heterodyne receivers, or (c) as control element for phase-locked telemetry receivers

Noninterruptable digital counting system Patent

Noninterruptable digital counter circuit design with display device for pulse frequency modulatio

Baseband signal combiner for large aperture antenna array

The invention provides a means whereby the baseband output signals of all but one of the receivers associated with each of the antennas are summed and used as a correlation reference for the baseband signal not contained in the summed signal, thereby providing a plurality of correlation or alignment loops, each having an output signal related to the phase difference between its input baseband signal and the summed signal. The invention further provides a means for subtracting an output or error signal generated in one of the correlation loops whose baseband signal has a predetermined phase delay from all the other alignment loops, thereby avoiding interaction and reflection effects in the signal combiner. A variable phase delay means for each of the other baseband signals is controlled by its corresponding correlation loop

Altered postural sway in patients suffering from non-specific neck pain and whiplash associated disorder - A systematic review of the literature

To assess differences in center of pressure (COP) measures in patients suffering from non-specific neck pain (NSNP) or whiplash-associated disorder (WAD) compared to healthy controls and any relationship between changes in postural sway and the presence of pain, its intensity, previous pain duration and the perceived level of disability. Summary of Background data: Over the past 20 years, the center of pressure (COP) has been commonly used as an index of postural stability in standing. While several studies investigated COP excursions in neck pain and WAD patients and compared these to healthy individuals, no comprehensive analysis of the reported differences in postural sway pattern exists. Search methods: Six online databases were systematically searched followed by a manual search of the retrieved papers. Selection Criteria: Papers comparing COP measures derived from bipedal static task conditions on a force plate of non-specific neck pain and WAD sufferers to those of healthy controls. Data collection and analysis: Two reviewers independently screened titles and abstracts for relevance. Screening for final inclusion, data extraction and quality assessment were carried out with a third reviewer to reconcile differences

Campylobacter jejuni bacteremia and Helicobacter pylori in a patient with X-linked agammaglobulinemia

We describe a 15-year-old patient with X-linked agammaglobulinemia who developed malabsorption and bacteremia due to infection of Helicobacter pylori and Campylobacter jejuni. The Campylobacter bacteremia was only recognized after subculturing of blood culture bottles that failed to signal in the automated system. After 2 weeks of treatment with meropenem and erythromycin for 4 weeks, the patient developed a relapse of bacteremia 10 months later with a high level erythromycin resistant C. jejuni. Sequencing revealed an A2058C mutation in the 23 S rRNA gene associated with this resistance. Treatment with doxycycline for 4 weeks finally resulted in complete eradication. This case report illustrates the importance for physicians to use adapted culture methods and adequate prolonged therapy in patients with an immunodeficiency. A summary of published case reports and series of patients with hypogammaglobulinemia or agammaglobulinemia with Campylobacter or Helicobacter bacteremia is given