Abstract: According to the prior art, springs (11/18) of a combination mask/frame (10) of picture tubes are joined to the frame by resistance welding. This welding technique is also customary when one of the springs (18) has a centering washer (20) at its free end. When combination mask/frames (10) designed in this manner are snapped repeatedly into and out of the shielding case (15), and when the shielding case (15) is stabilized or fritted to the neck of the picture tube, it can happen that the expansion characteristics of the combination mask/frame (10) are not homogeneous at the fourth spring (18) as compared to the other springs (11) under the picture tube's operating conditions.

Abstract: According to the invention, a contact for loudspeakers (10) is indicated between the wire ends (24) of voice coil (16) and the stationary contacts (19), which is temperature-stable even above 250.degree. C. This is achieved by first conductively connecting the wire ends (24) to the connecting lines (21), and then attaching the connected parts (21, 24) at least to one side of a high-temperature-resistant plastic foil (25). The plastic foil (25) is affixed to the diaphragm (13) or the voice coil support (14) by mechanical attachment means (23). The fact that the plastic foil (25), which stabilizes the connecting lines (21), is installed afterwards, allows the connection between the wire ends (24) and the connecting lines (21) to be performed by the ultrasonic welding technique.

Abstract: It is known to provide picture tube parts with identification marks. According to the state of the art, this identification of picture tube parts is achieved by attaching special layers or labels containing the identification data to the outside of the glass pans (10). However, this technique is extraordinarily costly because of the additional layers or labels. The invention shows that the respective identification marks (16) are formed directly on a first functional layer applied to the inside (19) of the respective picture tube part. The process is very simple if the respective identification marks (16) are burned into the first functional layer by means of a laser.

Abstract: The invention introduces an arrangement which maintains the usefulness of a fader control (11) connected for example to an audio signal source (10), and at the same time considerably reduces the circuit cost. This is realized in that the distribution to different listening areas adjusted by the fader control (11) is determined from the audio signals that are present behind the fader control (11). To that end, first the audio output signals (L, R) are reconstructed in two adders (12.2, 12.3) and routed to a fourth adder (12.4). Two each audio signals (L.sub.V, R.sub.V) are routed to a first adder (12.1). The signals existing behind the adders (12.1/4) are then placed into a ratio with each other by a divider (20). From the quotient Q determined there, the distribution rate is then determined by a calculator (21) and made available to the multipliers (M1-4). Devices (17) to determine the average level value, followed by smoothing devices (18), which are positioned symmetrically with respect to the adders (12.

Abstract: In the state of the art, most loudspeaker diaphragms 10 and the voice coil supports 11 are joined by adhesives. However, even high-grade adhesives fail if such loudspeakers are subjected to continuous operating temperatures much above 120 degrees Celsius. The one-piece construction of loudspeaker diaphragm 10 and voice coil support 11 is also limited. It is particularly difficult to produce one-piece metal constructions by means of the deep-draw process. It is therefore the task of the invention to present a joint of loudspeaker diaphragm 10 and voice coil support 11, which is simple to produce, can be subjected to high temperatures and is free of adhesives. This task is fulfilled in that the upper rim 19 of the voice coil support 11 is flared together with the upper rim 16 of a neck 12 formed on the diaphragm 10. In addition the invention proposes to join the neck 12 of loudspeaker diaphragm 10 to the voice coil support 11 through the effect of a ring-shaped part 23.

Abstract: In the state of the art, it is known to connect diaphragms (11) of cone loudspeakers to the loudspeaker frame (10) by means of so-called beads (13). Such beads (13) are predominantly made of plastic or rubber, and are connected to the diaphragm (11) or the loudspeaker frame (10) by means of suitable adhesives. This type of connection limits the free selection of the above named components, because not all elastic bead materials can be connected to the diaphragm (11) with the required mechanical stability. The selection of materials is further restricted when the loudspeaker is subjected to ambient temperatures above 100.degree. C., because the adhesive connections lose their strength under such conditions. The invention has therefore the task of presenting a high-strength suspension mount for the diaphragms of cone loudspeakers. This task is fulfilled in that the bead (13) is made of an injection-moldable and high-temperature resistant elastomer material (e.g.

Abstract: According to the state of the art, LC displays are known whose torsion angle is between about 180.degree. and 300.degree.. Such displays exhibit good independence of angle of view of white impression and contrast, but they are not gray scale capable and are not free of hysteresis. For that reason, the invention presents a display (10) whose product of plate separation (d) and anisotropy of the angle of refraction is equal to or greater than 0.45 and smaller than 0.65 .mu.m, whose torsion angle .phi. is between 260.degree. and 360.degree., whose liquid crystal molecules (18) have an approach angle .theta. between 7.degree. and 25.degree., and encompass a liquid crystal material between the substrate plates (11) in which the relationship of the elastic constant K.sub.3 to the elastic constant K.sub.1 is between 1.4 and 0.6. The angular relationships (.beta., .gamma.) of the polarization directions P.u, P.o with the respective orientation direction .eta..u, .eta..o is a function of torsion angle .phi..

Abstract: The invention relates to a device to be used for changing the acoustic properties of a room, comprising a pressure transducer (1), a loudspeaker (2) and an electronic control circuit (3) adapted to generate, in response to pressure changes in the room, an electrical signal that serves to cancel the pressure change detected by the pressure transducer (1) when it is reproduced through the loudspeaker. For improving the properties of the room also with respect to reverberation, the device of the invention further includes an ambience generator (4) adapted to receive an electrical signal proportional to the sound present in the room and to generate, in response to said signal, a signal which produces an acoustic field containing early reflections and reverberation in the room when reproduced through the loudspeaker (2).

Abstract: According to the state of the art, high-temperature resistant centering of loudspeakers is configured so that a rod (17) that is connected to the pole body (14) serves as a guide for a bushing (19) connected to the voice coil support (11). However, the narrow space between the rod (17) and the bushing (19) leads to friction between the rod (17) and the bushing (19) during excursion movements of the voice coil support (11), which retards the free movement of the voice coil support (11). The invention therefore has the task of providing high-temperature resistant centering for loudspeakers, in which any touching of rod (17) and bushing (19) is eliminated. The invention makes the rod (17) and the bushing (19) from magnetic material, and magnetizes this material radially to the loudspeaker axis (16). If the facing magnetic areas of rod (17) and bushing (19) have the same polarity, no-contact centering of the bushing (19) over the rod (17) is achieved by the mutual rejection.

Abstract: According to the state of the art, double chamber bass reflex boxes are constructed so that the housing is separated by a partition wall into two spaces (13, 14). A loudspeaker (19) is inserted into the partition wall. One of the two spaces (13, 14) is equipped with an outlet opening, into which a so-called bass reflex tube is inserted for tuning the box. If complicated housing shapes are to be manufactured, it is not possible to build the bass reflex tube and the wall to which it is connected, in one piece. In such instances it is rather necessary to insert the so-called bass reflex tube into an opening in the wall, and to attach it by means of suitable sealing and connecting means. For that reason the invention has the task of presenting a housing for double chamber bass reflex boxes (10) which is especially easy to produce.

Abstract: An anti-distortion device, connected downstream of a transmitting device (2) with a determined transmission bandwidth for transmitting a input signal (Se) with signal jumps (3), wherein the delay time (Tv15) of the delay element (15) is such that the front slope (24) of the detection signal (S18) of the second signal jump detector (18), produced when a slope (4) of the useful signal (Sa1) is detected, is at least partially located in the time range (T25) of the trailing edge (25) of the corresponding detector signal (S17) of the first signal jump detector (17), that the delay time (Tv11) of the delay element (11) is equal to half the period (T5) of the overshoot (5) superimposed on the useful signal, and following the signal slope (4) of the transmitted signal (Sa1), and that the delay element (10) is connected between the output (1) of the transmitting device (2) and the input (11.1) of the delay element (11).

Abstract: The invention relates to a sound reproduction system comprising a source of a sound signal in electrical form, a first filter group for dividing the signal derived from the sound signal source into several sound signals occurring in different frequency bands and an adjustable gain amplifier for each frequency band for amplifying the sound signal occurring in said frequency band. To take into account the noise existing in the environment of the sound reproduction system in the adjustment of the system, the system further comprises means for generating an electrical signal proportional to the background noise existing in the environment and means for adjusting the gain of the amplifiers in response to said electrical signal proportional to the background noise.

Abstract: Wired into the transmission path (2) of a transmission arrangement (1) to transmit a useful signal (NS), especially an audio or data signal, that is modulated onto a carrier signal (TS), is a bandpass filter (5) whose filter quality (G) can be adjusted. An error signal circuit (9) connected to the transmission path on the output side of the bandpass filter detects missing or excessively low amplitudes of the carrier signal and produces therefrom an error frequency signal (FS) with which, by means of a characteristic curve (G=f(FS)), the quality of the bandpass filter (5) is set and thereby the bandpass filter (5) is switched, in the manner of a cross-fade, from a wide transmission bandwidth to a high voltage superelevation in order to regenerate the amplitude of the carrier signal.

Abstract: The invention relates to a system for processing an audio signal to reduce the noise contained therein, the system comprising a source (1) of an audio signal in electric form, a first filter group (2) for dividing the audio signal into several subband signals in different frequency bands, a detector (3) for each subband signal to detect the audio signal level thereof, and a compressor/expander (4) for compressing/expanding each subband signal on the basis of the detected audio signal level thereof, and a second filter group (5) for combining the compressed/expanded subband signals to generate a reconstructed audio signal (6). According to the invention the first filter group (2,5) is arranged to divide the sound frequency range into bands with a width enabling the processing of the signal within the critical bands, and each compressor/expander (4) is arranged to attenuate the signal in its band when the detector (3) associated therewith has detected that the audio signal is missing from said frequency band.

Abstract: Inserted in the transmission path (10) for transmitting a color signal of a color television signal is a signal switcher (12) with at least three switch positions (12a, 12b, 12c), the end positions of which are connected to the output (11.2) and input (11.1), respectively, of a delay line (11) contained in the transmission path. Connected to the transmission path (8) of the luminance signals is an edge detection arrangement (24) which, when a signal edge is detected in the luminance signal, generates a detection signal that oscillates about a zero line and has a zero crossing at the detection time, and controls the signal switcher in such a way that an associated color signal edge of the color signal, which has a steep slope and occurs at the point in time of the signal edge of the luminance signal, is transmitted. In the absence of detection of a signal edge, portions of both the undelayed and the delayed color signal are transmitted to the signal output (12.3) of the signal switcher.

Abstract: A calibration step is carried out on a calibration tube in which magnetizations which cause beam displacements in x and y directions are determined for all the magnet poles and beams, and the adjustments of sensitivity of each beam from the x/y values is determined. A beam deviation of a production tube is then adjusted by determining its initial error in x and y directions and then starting a calculation sequence in which the magnetization currents are calculated by linear superposition of the individual currents on the basis of the known adjustment sensitivities. An additional rotating and decreasing auxiliary field is active during the magnetization of the poles in the rings of the calibration tube and of the production tube. It is also possible to correct twist errors using the invention.

Abstract: An active noise cancellation system, comprising a circuit for generating one or more reference signals (x(n)) proportional to the noise in the target area, several electronic circuits (1) having adjustable transfer functions (W), such as adaptive filters, adapted to receive the one or more reference signals (x(n)) and to generate noise cancellation signals (y(1,n)), sound sources (2) adapted to receive the noise cancellation signals (y(1,n)) and to generate cancellation noise in the target area for at least partial cancellation of the noise present therein, sensors (3) for detecting residual noise in the target area and converting it to electrical residual noise signals (e(m,n)), transmission path (4) having the estimated transfer function (C') of the transmission path between the electronic circuit (1) and the sensors (3) adapted to receive the one or more reference signals (x(n)), and tuning circuit (5) adapted to receive the residual noise signals (e(m,n)) and output signals from the transmission path circ

Abstract: A process for measuring a targeting of an electron beam that passes through a slot in a shadow mask in a multiple-beam color picture tube and strikes a phosphor stripe on a screen of the tube includes: exciting a luminous stripe in the phosphor stripe, recording an image of the luminous stripe with an image converter, determining outer edges of the phosphor stripe, generating an electron beam in the picture tube to illuminate a luminous spot on the phosphor stripe, recording an image of the luminous spot, determining positions of outer edges by analyzing the image of the luminous spot, and comparing locations of the outer edges of the phosphor stripe with the positions of the outer edges of the luminous spot to determine the targeting of the electron beam.

Abstract: A color TV convergence measurement device and process for measuring a position of an electron beam of a multiple-beam color picture tube relative to a field of view of an image converter, in which an electron beam generation system provides the electron beam which generates a brightness distribution pattern on a screen of a tube, the screen has phosphor stripes for different colors, and a shadow mask is arranged in front of the screen and has elongated slots in the direction of the phosphor stripes.

Abstract: It is known in the state of the art to equip conical loudspeakers, which are suitable for reproducing long excursion or wide band audio signals, with magnet systems (10), which contain a ring-shaped permanent magnet (12) made of ferrite. To make the induction, required by these magnet systems (10), available in the air gap (20), it is necessary to design the permanent magnets (12) in a large size. It is also known to construct short excursion magnet systems in such a way, that the pole core is made of a high energy magnetic material (-neodymium). This pole core is located in the center of a pot magnet. Such magnet systems, which have the same output and can be built considerably smaller and lighter than the types of magnet systems (10) mentioned first, cannot be transferred to the magnet systems (10) that are suitable for the reproduction of wide band or long excursion audio signals, because a neodymium pole core is not able to produce the induction in the air gap required by such magnet systems (10).