摘要:
Circuitry for computing the square root of a number wherein the input number is partitioned into digit pairs left and right of the radix point. Pairs of zeros are added after the radix point for each digit of the desired precision. The most significant zero digit pairs are skipped to the first digit pair which is not zero, accordingly the first answer bit is a 1. A residue is formed by subtracting the 1 from the digit pair, multiplying by 4, and adding the next most significant digit pair. The procedure is repeated for subsequent bit pairs by defining trial divisors and determining residue values.
摘要:
A mixer for mixing first and second signals for providing a difference signal comprises a mixing transistor (200). The first and second signals are applied between the base and emitter electrodes of the transistor. A non-linear impedance (212) is coupled in series with the emitter electrode. Spurious signal components are reduced in amplitude compared with the difference signal.
摘要:
Disclosed is a programmable logic gate array employing a plurality of reprogrammable fuses (20) having a logical NAND characteristic for logically connecting selected inputs (A o -A n ) to selected logic gates (22). Means E 5 , P s are also disclosed for programming said fuses and for providing appropriate signals to allow three modes of operation of the logic gate array; programming, erasure and normal logic operation.
摘要:
A degaussing circuit for a cathode ray tube of a video display apparatus includes a resonating capacitor (C1) that is charged prior to degaussing. A degaussing coil (L DG ) is disposed about the cathode ray tube. An SCR (SCR1), responsive to an on/off control signal, is turned on by a control switch (Q1) for coupling the resonating capacitor (C1) to the degaussing coil (L DG ) in order to generate an AC degaussing current in the coil having an amplitude that diminishes to a low amplitude during a degaussing interval. Positive feedback (R2,C2) is used for speeding up the turn-on time of the control switch (Q1). A series pass transistor switch (Q2) couples a source (T1 or 51) of a supply voltage (VUR1) to a delay network (R7,C5). The series pass transistor switch (Q2) is coupled in the current path of the current that is supplied by the power supply. An energizing voltage (V Q ₂) is developed at the output of the delay network (R7,C5). The magnitude of the energizing voltage exceeds a predetermined value after a predetermined delay time following conduction of the transistor switch (Q2), that is determined by the delay network. The delayed energizing voltage is coupled to a deflection circuit (56,57,58) to initiate deflection circuit operation after conclusion of the degaussing.
摘要:
A timing system (Fig. 1) ordinarily includes: a timer circuit (24), a source (11, 14) of first clock pulses for advancing the timer circuit, and a circuit (16, 18) for reading out the timer circeit in delayed synchronizism with the clock pulses. In order to allow the timer circuit to be advanced by second clock pulses from a second source (29), where the second clock pulses are asynchronous with respect to the first clock pulses, there is provided a synchronizing or storage circuit (32) for storing an indication of the occurrence of each second clock source pulse. The timer circuit is advanced only when there are present the stored indication and the next-occurring first clock pulse. The stored indication thereafter is erased, in anticipation of receipt of the next-occurring second clock pulse.
摘要:
The cathode-ray tube (10) includes a faceplate panel (12) and an electron gun (14), adapted to emit a beam of electrons for striking a cathodoluminescent screen (16) disposed on the panel. It has a conductive loop (28) disposed around the perimeter of the screen for locally altering the trajectory of the electron beam adjacent the perimeter, thereby achieving a focusing effect for reducing the size of cathodoluminescent spots adjacent the perimeter of the screen. The conductive loop has a significantly lower voltage applied thereto than to the screen.
摘要:
An inline electron gun (26:26') for a cathode-ray tube (8) includes an improved beam forming region comprising three cathodes (34), a control grid (36) and a novel screen grid electrode means (38, 38'), the latter comprising two spaced apart metal members (G2a, G2b;G2a',G2b'). In one embodiment (26), the first member (G2a) closest to the control grid is relatively thick and has three slots (52) formed in one surface thereof facing away from the control grid. Circular apertures (54) are formed within the slots and extend through the body of the first member. The second member (G2b) has three circular apertures (56) therethrough aligned with the circular apertures in the first member. When a dynamic signal is superimposed on the DC bias voltage and applied to the second member, the first member shields the control grid from the dynamic signal so that little or no brightness modulation occurs. In a second embodiment (26'), the first (G2a') and second (G2b') members of the screen grid (38') are structurally interchanged. In a third embodiment, the first (G2a) and the second (G2b) members have orthogonally disposed rectangular slots formed in facing surfaces.
摘要:
Phase detectors (202, 204) in a progressively scanned television receiver measure the phase of the receiver video speed-up memory read (8 fsc ) and write (4 fsc ) clocks with respectto the double line-rate horizontal sweep signal (FB) of the display. Delay means (34, 36) are provided for delaying the video signal recovered from the memory (30, 32) as a function of the difference (224) between the read and write clock phase measurements each time the memory is read. The delay is effective for minimizing visible artifacts which otherwise may tend to occur when displaying "non-standard" video signals wherein the ratio of the color- subcarrier frequency to the line-frequency of the incoming video signal differs from a given broadcasting standard.
摘要:
In a color TV receiver incorporating automatic kinescope bias (AKB) control circuits, a first train (rb) of monolevel pulses with timing suitable for retrace blanking purposes and a second train (bg) of monolevel pulses with "backporch" timing appropriate for burst gating purposes are applied to a circuit serving to generate at a first terminal (P) a train of bilevel pulses exhibiting a first voltage level during periods of overlapping of the pulses of the first and second trains, and exhibiting a second, lesser voltage level during the remaining, non-overlapping portions of the pulses of the first train. A resistor (30) interconnects the first terminal with a second terminal (J). A keyed voltage source (33), responsive to a third train (a) of monolevel pulses timed to indicate recurring kinescope bias control intervals, develops a voltage of a third level, intermediate the first and second voltage levels, at the second terminal during-the recurring control intervals. The keyed voltage source exhibits, during the control intervals, an output impedance significantly lower than the impedance exhibited by the interconnecting resistor (30). During periods intervening successive ones of the control intervals, the voltage source is effectively disabled and exhibits an output impedance significantly higher than the impedance exhibited by the resistor.
摘要:
The signal separation system operating at a reduced data rate requires comparably fewer storage locations than previous arrangements. Such a signal separation system, for use in a television receiver, separates two sampled data video signal components which are interleaved in frequency. This system comprises means (12) for passing the sampled data video signal at a data rate less than the original sampling rate. A comb filter (20) is responsive to the reduced sample rate signal, and produces the comb-filtered output signal.