Abstract: Digital filter used in a sigma-delta decoder wherein each input sample is involved in the computation of three consecutive pulse coded modulation (PCM) output samples. During one sigma-delta sampling period, the filter performs three parallel operations by multiplexing one adder running three times faster than the sigma-delta clock for loading one of three accumulators. As the analog-to-digital converter must be kept in phase with remote modem transmit clock, the PCM sampling clock is controlled by the phase tracking performed by adding or subtracting one period of the crystal oscillator from time to time to the PCM sampling clock period. Rotating the order in which the accumulators are loaded by the adder each PCM sampling time enables having zero as the last coefficient value to add to the accumulator, the contents of which is used as PCM output samples. Thus, each PCM sample value is available in the corresponding accumulator one sigma-delta clock period before the last computation.

Abstract: The shock absorbing jack of the invention includes essentially a rod in which a sliding piston defines an extension chamber and which itself slides in a body by means of a piston defining a retraction chamber, the body including a throttling device and, on the side opposite the rod, two high and low pressure gas chambers, these chambers being separated by a membrane bearing, at rest, on a support with hemispherical perforated bottom.

Abstract: A magnetic bubble store including at least two series of longitudinally oriented major shift registers and a rotating magnetic field for producing a displacement of the bubbles in the minor registers. The series of minor registers are respectively arranged on either side of a transverse boundary. The minor registers of each of the series are constituted by motifs defined by ion implantation in a magnetic garnet layer. On either side of the boundary, these motifs define complementary distributions of implanted areas and non-implanted area.

Abstract: A magnetic bubble store formed of a series of longitudinally oriented shift registers and at least one transversely oriented access contour register having a single access point corresponding to each access end of each longitudinally oriented shift register, wherein magnetic bubbles are displaced in the longitudinally oriented shift registers by applying a rotary magnetic field thereto, and wherein magnetic bubbles are displaced in the transversely oriented access contour register by applying an electric current thereto. The longitudinally oriented registers are formed of motifs defined by ion implantation in a magnetic garnet layer.

Abstract: Machine for testing planar magnetic film with magnetic bubbles and which comprises a testing device and a magnetic head, wherein the magnetic head incorporates two polarization coils in the Helmholtz position and whereof the common axis is normal to the plane of the magnetic film and two flat coils whose axes are perpendicular to one another and parallel to the plane of the magnetic film, the first of the polarization coils being arranged within the flat coils which are themselves arranged one within the other and on the same side of the magnetic film, while the test device and the second polarization coil are arranged on the other side of the magnetic film.

Abstract: A voice signal is transmitted digitally at reduced bit rate by use of data compression. The original frequency components of a telephone band width of the voice signal sampled at 8 KHz and quantized with 12 bits are transformed into three parameters: SIGNAL data representing adaptive quantization for lower frequency (300-800 Hz) sub-bands; COEF data representing pre-emphasized parcor type coefficients for the higher frequency (800-3000 Hz) band; and, ENERGY data representing higher frequency short term energy level. The three parameters are multiplexed for transmission in binary-code form, thereby representing a recoding of the original binary-coded voice signals.