Abstract: A facsimile apparatus comprises a communication control unit for establishing a connection, the communication control unit sending station identification data to a calling station and receiving station identification data from a called station for identification of the station, an image data transmission and reception unit, an image reading unit, an image recording unit, a memory for storing the station identification data of selected stations; and a memory control unit for controlling the memory such that, when a call is made to a called station, the station identification data that is returned from the called station is stored in the memory as the station identification data of the selected stations. The communication control unit rejects reception of the image data transmitted from the calling station when the calling station is not included in a list of stations stored in the memory.

Abstract: A receiver having a signal path incorporating a tuner, a demodulator circuit for supplying a stereo multiplex signal having a baseband stereo sum signal (L+R), a 19 kHz stereo pilot and a stereo difference signal (L-R) which is double sideband amplitude-modulated on a suppressed 38 kHz subcarrier, a sampler for converting an analog signal into a time-discrete signal and a stereo decoder for time-division multiplex decoding of a time-discrete stereo multiplex signal into time-discrete left and right stereo signals. In order to realize an effective selection of the stereo multiplex signal by an easily integrable low-pass filter, the stereo decoder includes a time-discrete halfband low-pass filter circuit having a finite impulse response, with a transition band which is substantially located in the frequency range of said modulated stereo difference signal and with a half-value transfer which is located at the frequency of said 38 kHz stereo subcarrier.

Abstract: The invention comprises a back-masking effect generator which produces, almost in real time, the simulated sound of an input audio signal being reproduced in reverse. The device digitally records the sound in packets of short duration with alternating packets being written to first and second static random access memory devices, respectively. After an initial state in which the first memory device is filled with the digitized input audio signal, the generator then continuously alternates between two other states. In one state, the second memory device is filled while the first memory device is simultaneously emptied to a digital-to-analog converter in the reverse order from which it was filled. In the other state, the first static random access memory is filled while the second memory device is simultaneously emptied to the digital-to-analog converter.

Abstract: A loudness control circuit having a sound volume adjusting variable resistor with a center tap is provided. The loudness control circuit has a buffer circuit of low output impedance having an input terminal to which a sound signal is applied through a high frequency coupling capacitor. The output terminal of the buffer circuit is connected through a series circuit of a low frequency blocking capacitor, a protective resistor and a shunt resistor to the center tap of the sound volume adjusting variable resistor. The connecting point of the protective resistor and the shunt resistor is grounded through an electronic switching element. The electronic switching element is turned on and off for the on-off control of loudness.

Abstract: A truck rear window includes a first window plate and second window plate, each including a window plate opening to pivotally mount at least one speaker housing therewithin. The speaker housing includes a speaker therewithin and is pivotally arranged to permit projection of sound to an interior passenger compartment of a truck cab or rearwardly relative to the truck bed to project music exteriorly of the truck cab. The speaker housings each include diametrically aligned axles directed into respective window plates of the truck window and a frictional perimeter covering to effect weather strip sealing, as well as frictional engagement relative to the window opening of each respective speaker. The truck window may include a central plate arranged for disengagement relative to the first and second window plates to permit ventilation through the truck cab.

Abstract: A new and improved decoder for decoding CCITT compressed image data. This decoder separates all the incoming codes into short codes and long codes. The short codes are sent to the short channel decoder and the long codes are sent to the Long Channel decoder. The short channel decoder has a twin set decoder which decodes two short codes in parallel and guarantees two bits of decompressed data per clock cycle. The Long Channel decoder decodes the long codes which always generate at least four bits of decompressed data. A look ahead logic determines the a0b1 and a0b2 relative distances for each of the next two codes to be decoded on the next clock cycle, while the current codes are in the process of decoding. The look ahead logic helps to increase the decoding speed.

Abstract: A cathode-ray tube comprises an evacuated envelope which includes a faceplate panel joined to a funnel. A shrinkfit implosion protection band of at least one strip of metal, having oppositely disposed ends, is secured together at a connective joint to form a loop with cold dimensions slightly smaller than the periphery of the panel prior to application of the band. The band has a given sectional area with at least one opening formed therethrough. The band is fitted around the periphery of the panel to apply a compressive force thereto, as a result of the tension of the band. The band is improved by providing at least one slot within the band and in communication with the opening, to reduce the sectional area of the band sufficiently to lower the tension of the band below the minimum design limit of the connective joint.