Abstract: Method for operating a reception apparatus for radio-frequency signals, wherein at least two antennas (2, 4) for receiving and further processing the radio-frequency signals are provided, wherein the reception quality of the received radio-frequency signals is taken as a basis for effecting changeover, characterized in that the entire frequency range of the radio-frequency signals received by the respective antenna (2, 4) is converted from analogue to digital signals by means of a wideband converter (6, 7), and then frequency selection takes place.

Abstract: A method and a device for a receiver for electromagnetic waves having at least two antennas are described; using this method and this device it is possible to effectively suppress multipath interference, while a portion of the antenna signals may also be utilized for other purposes at least temporarily, e.g., to allow better utilization of the possibilities of RDS activities. To do so, a first antenna signal (1) is used as the basis for generating a playback signal (23) when the signal quality of the first antenna signal (1) is above a defined threshold for undisturbed reception—case 1. In this case 1, the signal quality of the first antenna signal (1) is determined. If the signal quality of the first antenna signal (1) falls below this threshold—case 2—then a new signal y generated from at least two antenna signals (1, 2) is used as the basis for generating the playback signal (23).

Abstract: A drive for storage disc which permits a convenient means of loading and unloading the storage disc. The drive includes a loading device for transport of a storage disc into the drive, the loading device including a carrier for accommodating the storage disc. In a loading position, the carrier remains generally in the drive and, in the direction of an insertion opening of the drive, includes an opening for insertion of the storage disc.

Abstract: A method is proposed that is used for activating the functions of an electrical device, preferably a car radio. A test routine stored in a storage area allocated to the device is executed by a control unit of the electrical device. The control unit activates at least one function of the electrical device on the basis of control commands predefined in the test routine. Information about the function just activated is reproduced on a reproducing device of the electrical device.

Abstract: A disk drive is described, having a draw-in device for disk-shaped storage media, which prevents damage to the playoff area of such storage media. The draw-in device includes a threaded rod having an axis of rotation in the push-in direction of the storage medium. The course of thread of threaded rod acts together with the edge region of a storage medium inserted into the draw-in device so that the storage medium is drawn into the disk drive or pushed out of the disk drive by the rotation of the threaded rod, depending on the direction of rotation.

Abstract: A drive for storage disc which permits a convenient means of loading and unloading the storage disc. The drive includes a loading device for transport of a storage disc into the drive, the loading device including a carrier for accommodating the storage disc. In a loading position, the carrier remains generally in the drive and, in the direction of an insertion opening of the drive, includes an opening for insertion of the storage disc.

Abstract: A method and a circuitry for demodulating a digital frequency-modulated signal. After demodulating the digital frequency-modulated signal for generating the signal's amplitude and differential phase value &phgr;, the amplitude of the demodulated signal is compared with a constant at determined sampling times. The phase value of each sampling time is multiplied by a factor, the factor (c) being the product of the amplitude of the determined sampling time and the amplitude of a preceding sampling time, if the amplitude is less than the constant.

Abstract: A method and a device for a receiver for electromagnetic waves having at least two antennas are described; using this method and this device it is possible to effectively suppress multipath interference, while a portion of the antenna signals may also be utilized for other purposes at least temporarily, e.g., to allow better utilization of the possibilities of RDS activities. To do so, a first antenna signal (1) is used as the basis for generating a playback signal (23) when the signal quality of the first antenna signal (1) is above a defined threshold for undisturbed reception—case 1. In this case 1, the signal quality of the first antenna signal (1) is determined. If the signal quality of the first antenna signal (1) falls below this threshold—case 2—then a new signal y generated from at least two antenna signals (1, 2) is used as the basis for generating the playback signal (23).

Abstract: A radio receiver having a circuit arrangement for checking the quality of reception at an alternative frequency to a received transmit frequency. The radio receiver has two tuners for converting the received signals to two different intermediate frequencies and a switch, which is preferably switched by a microprocessor, for optionally forwarding signals from signal processing branches that are each connected to one of the tuners. This reduces the cost of implementing the second receiver, at the same time reducing the barely noticeable impairment of the set program when checking the quality of reception at the alternate frequency. The latter is achieved by positioning the switch upstream from an analog-digital converter, operating at a sampling frequency, of an intermediate frequency stage. The different intermediate frequencies are selected so that they both meet the following condition: f0=(n+R)fa where n is a natural number, and 0≦R≦1 applies.

Abstract: A disk drive (1) is proposed, having a draw-in device (5) for disk-shaped storage media (10), which prevents damage to the playoff area of such storage media (10). The draw-in device (5) includes a threaded rod (15) having an axis of rotation (20) in the push-in direction (25) of the storage medium (10). The course of thread (30) of threaded rod (15) acts together with the edge region (35) of a storage medium (10) inserted into the draw-in device (5) in such a way that the storage medium (10) is drawn into the disk drive (1) or pushed out of the disk drive (1) by the rotation of the threaded rod (15), depending on the direction of rotation (40).

Abstract: The method for obtaining the quality signal includes multiplying a digital multiplex signal (MPX) by respective reference carrier signals mutually phase shifted by 90.degree. to each other, but otherwise equal, to form a pair of mixed signals (Imr1,Imr2); multiplying the mixed signals (Imr1, Imr2) by respective correction signals (G38c,G38s) to form a pair of corrected mixed signal (Ims1,Ims2); separately multiplying the digital multiplex signal (MPX) by each of two reference pilot signals mutually shifted in phase by 90.degree.

Abstract: A radio receiver is provided having digital signal processing, a first and a second auxiliary signal derived from a received stereo multiplex signal, the first auxiliary signal being dependent upon the existence of signal components, whose frequency lies above the fundamental frequency range of the stereo multiplex signal, and the second auxiliary signal being dependent upon the symmetry of the sidebands of the stereo subcarrier. The first and the second auxiliary signal are combined to form an interference signal indicating the existence of interference. At least one control signal is derived from the interference signal to influence the audio signals acquired by decoding the stereo multiplex signal.

Abstract: The circuit arrangement includes a first low-pass filter (2) for filtering an input signal (H3) proportional to the strength of a received radio signal; a second low-pass filter (3) for filtering the input signal (H3); a first weighting circuit (7) for weighting the first low-pass filter output signal with first coefficients to form a first weighted output signal; a circuit device for forming a masking signal for reducing stereo channel isolation from the first weighted output signal; a second weighting circuit (5) for forming a second weighted output signal weighted with second coefficients from the first low-pass filter output signal or the second low-pass filter output signal according to a switching signal (DD2) indicative of interference in the audio signals; a switch device (4) for selecting the first low-pass filter output signal for weighting in the second weighting circuit means (5) when no interference is indicated by the switching signal (DD2) and the second low-pass filter output signal for weight

Abstract: A circuit arrangement for deriving the signal indicating noise in a received stereo multiplex signal, wherein the stereo multiplex signal is present as a digital signal with a first sampling rate that is substantially higher than twice the upper limit of the useful frequency range of the stereo multiplex signal, and the received stereo multiplex signal is passed through a low-pass filter. The low-pass filtered signal and the received stereo multiplex signal are subjected to decimation to a second sampling rate, which is higher than twice the upper limit of the useful frequency range of the stereo multiplex signal. The two stereo multiplex signals with the second sampling rate are subtracted from one another.

Abstract: In a radio receiver with digital signal processing, a stereo multiplex signal received and the useful signals derived therefrom are processed in digital form at a first sampling rate. The subsidiary signals derived from the stereo multiplex signal are at least partly processed at a second sampling rate that is smaller than the first sampling rate. The sampling rate of the processed subsidiary signals are reduced to the first sampling rate with the processed subsidiary signals, acting as control signals with the first sampling rate, affecting the stereo multiplex signal and the useful signals.

Abstract: In a circuit arrangement for deriving a signal dependent on the change direction of the incoming signal level in a radio receiver, controllable by a microcomputer, a comparator is provided outside the microcomputer to which a signal representing the respective signal strength and a signal generated by the microcomputer representing the signal strength at an earlier point in time can be supplied. An output signal from the comparator can be supplied to the microcomputer.

Abstract: In a digital circuit which removes ignition noise from a multiplex signal in a radio receiver, especially in a car radio, the multiplex signal is supplied via a high-pass filter (3) and a squaring or absolute value determing circuit (4) as a digital signal with a sampling frequency that is a multiple of the frequency of the pilot tone. The high-pass filtered and squared or absolute value multiplex signal is compared to a short-time mean value of the high-pass filtered and squared (in absolute value) multiplex signal. A control signal S of predetermined duration is formed when deviations occur that are greater than a preset standard. The control signal S controls a correcting circuit in such a manner that sampling values of the multiplex signal occurring during the control signal are replaced with sampling values occurring during the previous period of the pilot tone, thereby masking the ignition noise.

Abstract: In a circuit for a demodulator of a radio data signal in a radio receiver, the multiplex signal in digital form is mixed into the baseband, in two phase positions shifted 90.degree. with respect to each other, after band-pass filtering, together with a reference carrier generated at a sampling clock rate produced in the radio receiver, thus producing a first and a second mix signal. A first and a second auxiliary signal with, respectively, a sine waveform and a cosine waveform are produced. The first mix signal is multiplied by the first auxiliary signal, and the second mix signal by the second auxiliary signal. The results of these multiplications are added together, producing a first output signal. The first mix signal is multiplied by the second auxiliary signal, and the second mix signal by the first auxiliary signal, and the results subtracted from each other, thus producing a second output signal.

Abstract: In a circuit for digital processing of audio signals in a radio receiver, preferably in a car radio, the audio signals pass through a digital filter designed as a tone control, whose frequency response can be controlled with supplied coefficients, and a volume control, whose transmission factor can be controlled with supplied control signals. If the high and/or low frequencies are raised, the transmission factor of the filter at medium frequencies can be correspondingly lowered. Volume control compensates for the reduction. The volume control may contain a digital and an analog portion.

Abstract: In an amplitude demodulator for radio receivers, an intermediate frequency signal is converted into a digital intermediate frequency signal. The digital intermediate frequency signal is mixed into the baseband and amplitude demodulated. Either the intermediate frequency signal, or the amplitude demodulated signal, is controlled and amplified or attenuated so that the DC component of the amplitude demodulated signal is kept constant.