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    Improvements in electron valves
    54.
    发明专利
    Improvements in electron valves 未知

    公开(公告)号：GB795804A

    公开(公告)日：1958-05-28

    申请号：GB2116754

    申请日：1954-07-20

    Applicant: SOC NOUVELLE OUTIL RBV RADIO

    IPC: G06G7/26 ,  H01J3/02 ,  H01J13/50 ,  H01J21/02 ,  H01J29/52

    Abstract: 795,804. Thermionic cathode tubes. SOC. NOUVELLE DE L'OUTILLAGE R. B. V. ET DE LA RADIO-INDUSTRIE. July 20, 1954 [July 24, 1953], No. 21167/54. Class 39(1). In a thermionic valve the output signal of which is to be a desired function of the input signal, the effective area of the cathode utilized is varied by the application of said input signal to a control electrode, and the outline of the cathode area itself is given a particular shape dependent on the function required. Figs. 3A and 3B show examples of cathodes in which the active area lies between curves 12, or 121, respectively, the configuration of these outlines being determined by the required function. As the grid potential varies, the part of this area utilized varies. Such a cathode may be used in a straightforward triode construction, or in the construction of Fig. 4, where secondary-emissive anode 18 is surrounded by a final collector anode 19. The control electrode may be divided into two parts, to which different modulating voltages may be applied independently, so providing a more extended range of output-to-input relationships. The electrode construction may be duplicated on either side of a central cathode. Instead of an actual cathode, a virtual cathode may be used, the shaped cathode being obtained by allowing the electrons from the cathode image to pass through a shaped aperture. Fig. 7 shows such an embodiment, in which again the electrode structure is duplicated. The cathodes are emissive surfaces 23, 24 on the inside of a box-like structure 20. The electrons from cathode 24 travel in a curved path under the action of the magnetic field of a coil 26 to form a virtual cathode in the same plane at 21, where they pass through an aperture of the required shape, and then between separately controllable modulating electrodes 29, 30 to an anode 32. The electron density at the virtual cathode is varied according to the magnetic field, which thus affords a further control in accordance with a second independent variable. The output current can therefore be arranged as a function f(x) of the input signal x, or as the product f(x)F(y) of two functions, of two independent input signals x and y.

    Improvements relating to synchronizing and blanking signal generators for television
    55.
    发明专利
    Improvements relating to synchronizing and blanking signal generators for television 未知

    公开(公告)号：GB794724A

    公开(公告)日：1958-05-07

    申请号：GB2767054

    申请日：1954-09-24

    Applicant: SOC NOUVELLE OUTIL RBV RADIO

    IPC: H03L7/00 ,  H04N5/06 ,  H04N5/073

    Abstract: 794,724. Television. SOC. NOUVELLE DE L'OUTILLAGE R.B.V. ET DE LA RADIOINDUSTRIE. Sept. 24, 1954 [Oct. 6, 1953], No. 27670/54. Class 40 (3). In a circuit for generating television synchronizing and blanking waveforms wherein a master oscillator operating at twice line frequency feeds in parallel a multi-tap delay line and a frequency divider formed of a plurality of binary stages, the leading and rear edges of the pulses forming the waveforms being determined precisely by utilizing the outputs from the delay line taps which are gated as required under the control of a gate pulse generator actuated by the frequency divider, the gate pulse generator is an additive or " and " network formed of unidirectional elements, e.g. crystal diodes, connected in appropriate combinations to the stages of the counter. In a first embodiment, Figs. 2-4, see below, the invention is described as applied to the French 819 line system. In a second generally similar embodiment, Figs. 9-11 (not shown), the invention is described as applied to the 525 line, 60 frame system. Reference is also made without giving details to the 625 line, 60 frame system. Figs. 2 and 3 show the details of the blanking and synchronizing waveforms for the French 819 line system. The line synchronizing pulse AB is of 2.5 microseconds duration and occupies a position 0.5 microsecond from the front edge of the 8 microseconds blanking interval DE. The frame synchronizing pulse GC is of 20 microseconds duration and occupies a position six half lines from the front edge of the frame blanking interval IJ which is of 41 lines duration. In Fig. 4 master oscillator 10 operates at twice line frequency, i.e. 40,950 c/s., and supplies a pulse output through a wave-shaping circuit 12 to a multi-tap delay line 14 and a frequency divider 16. The output from tap D of the delay line determines the leading edge of the line blanking wave whilst that from tap E occurring 8 microseconds later determines the rear edge. Since the camera may be operated remotely from the transmitting apparatus, the actual blanking intervals appearing in the video waveform may be subject to delay, and in order to ensure accurate positioning of the blanking intervals with respect to the synchronizing signals, which are inserted at the transmitter, taps D and E are ganged together and made adjustable along the line. The leading and rear edges of the line synchronizing pulse are determined by the outputs from taps A and B respectively, tap A normally being spaced 0.5 microsecond in time from tap D. Since the front and rear edges of the frame blanking waveform coincide with line blanking, the output from tap D serves also to determine these instants. The leading edge of the frame synchronizing pulse coincides alternately with a line synchronizing pulse and the half-line position and may be determined therefore by the output from tap A. The rear edge of the pulse occurs 20 microseconds later and is determined by the output at a tap C due to the next following pulse into the line, tap C being chosen such that half the line duration minus the delay between taps C and A is equal to 20 microseconds. The frequency divider 16 comprises a chain of ten binary trigger stages, Figs. 5 and 7 (not shown), with feedback from an output circuit 86 to stages 1, 3, 4, 7 and 8 in order to reduce the count from 1024 to 819. The divider provides outputs therefore at the frame frequency of 50 c/s. The output from the final stage is derived through network 120 and further outputs at selected instants before the final stage output are provided on leads 61 and 62 by a gate pulse generator 18 comprising combinations of rectifiers, Fig. 6, connected to selected groups of counter stages. The output on lead 61 is employed for gating the front edge of the frame blanking waveform and occurs 41 lines before the final stage output, i.e. at count 430. The output on lead 62 is employed for gating the front edge of the frame synchronizing pulse and occurs six half lines after that on lead 61, i.e. at count 436. The two counts have binary digits 1, 3, 6, 7, 8, 9 and 10 in common. Thus the network of rectifiers consists of a common part 63 together with a part 64 and 65 individual to each count. Each rectifier is connected so as to be cut-off when the associated binary stage is in the desired condition, a positive output appearing on the common lead when all the rectifiers are cut-off. A negative output is arranged to appear on lead 62 by the inclusion of phase inverter 66. The output of the master oscillator through wave-shaping circuit 12 also drives a divide-by-two stage 102 to provide an output at line frequency. The line blanking waveform is produced by bi-stable multivibrator 22 and appears at output S2. The upper stage of the multivibrator is triggered by the pulses from tap D on the delay line, alternate pulses being selected by passing the output through a gate stage 91 controlled by divider 102, and the multivibrator is reset by the output from tap E which is applied through rectifier 104 and network 106 to the lower stage. The frame blanking waveform is produced by a similar multivibrator 23 and appears at output S3. The output from tap D determines both the front and rear edges in this case, the upper stage of the multivibrator being controlled by gate 96 in response to the frame frequency output on lead 61 and the lower stage being controlled by gate 100 in response to the counter output 41 lines later through network 120. The complete synchronizing waveform is produced at output S1 by multivibrator 21. The line synchronizing pulses are produced by the outputs from taps A and B, the output from tap A being applied to the lower stages of the multivibrator through gate 98 which is controlled to transmit alternate pulses by the output from divider 102 applied through a normally open gate 92, and the output from tap B being applied to the upper stage of the multivibrator through a normally open gate 94. The frame synchronizing pulse is produced in response to the output from gate pulse generator 18 on lead 62. This closes gates 92 and 94, and opens gate 98 thereby allowing the next following pulse from tap A to trigger the lower stages of multivibrator 21 whilst the inset takes place in response to the pulse appearing 20 microseconds at tap C and applied through network 108 to the upper stage.

    Improvements to television cameras
    56.
    发明专利
    Improvements to television cameras 未知

    公开(公告)号：GB790208A

    公开(公告)日：1958-02-05

    申请号：GB1390954

    申请日：1954-05-12

    Applicant: SOC NOUVELLE OUTIL RBV RADIO

    IPC: G03B19/18 ,  H04N5/225

    Abstract: 790,208. Lens turrets. SOC. NOUVILLE DE L'OUTILLAGE R. B. V. ET DE LA RADIO-INDUSTRIE. May 12, 1954 [May 27, 1953], No. 13909/54. Class 97(1) [Also in Group XL(b)] The lens turret 30 of a television camera is rotated by means of hollow shaft 108 extending to a handle 80 at the rear of the camera and includes a gear assembly 153, Figs. 3-5 (not shown), actuated by a shaft 116 extending through hollow shaft 108 to a knob 117, whereby the diaphragm settings of all the levers on the turret may be adjusted simultaneously. Shaft 116 may also be rotated by an electric motor 88 controlled remotely. Motion of shaft 116 is communicated to a potentiometer 119 which is connected in circuit with a milliameter calibrated to give a reading indicating the diaphragm setting. A detent mechanism 96, 100, 101, 103 released by pressure on a rear portion 82 of handle 80 is provided to ensure positive angular positioning of the turret. The turret together with the gear assembly is detachable'from the camera by releasing a spring- loaded wing nut 189.

    Improvements to filtering network
    57.
    发明专利
    Improvements to filtering network 未知

    公开(公告)号：GB785621A

    公开(公告)日：1957-10-30

    申请号：GB755955

    申请日：1955-03-15

    Applicant: SOC NOUVELLE OUTIL RBV RADIO

    IPC: H04B3/14

    Abstract: 785,621. Pulse-transmission networks. SOC. NOUVELLE DE L'OUTILLAGE R.B.V. ET DE LA RADIO-INDUSTRIE. March 15, 1955 [March 19, 1954], No. 7559/55. Class 40(8). [Also in Group XL (c)] A filter network has a transfer characteristic : where A and a are parameters independent of the frequency # 0 = # 0 /2 # of the signal. The function G(#) may be shown to be a Fourier transform of a sinusoidal oscillation of frequency f o modulated by a rectangular pulse of duration 2a and, on account of this fact, the network is stated to be particularly suitable for the detection of pulse-modulatd signals where random noise is present. The network may, however, be applied to the detection of pulses which do not modulate a carrier wave (# 0 = O). A network for transmission of pulses of deviation 2a having the characteristic G(#) may be realized by a number of elementary sections associated with a band-pass filter, each section comprising a delay line in parallel with a direct connection and an additive network, the delays introduced by successive sections being chosen to constitute a geometric series of decrement ¢. The largest delay introduced by the sections is made equal to a and should be equal to a multiple of half the period of # 0 where this exists. The band-pass filter may be in the input or output of the chain of sections or may be constituted by several elementary filters connected between successive sections and having different characteristics. In the embodiment of Fig. 4 the delay line comprises 40 identical LC sections and is terminated by a resistance R equal to its characteristic impedance. The direct connection 1 includes an attenuator R 11 which ensures that the amplitudes of the direct and delayed signals are equal. The signals are applied to the control grids of VI and V2 and the sum of the signals is derived from the anodes which are connected in parallel. The output signal is fed by means of a coupling capacitor C1 to the next stage 12 which is identical with the previous stage except that the delay line comprises only 20 LC sections. Stage 13 has a delay line comprising 10 sections and is connected to a band-pass filter 4 which may be reduced to a circuit tuned to the frequency # 0 . In a modification, the output from the attenuator R11 is applied directly to the delay line of the following stage, the valve V2 being omitted. In the circuit of Fig. 5 the delay line is open circuited and is connected in parallel with a resistor R equal to its characteristic impedance in the anode circuit of an amplifying valve V5. Since the pulse is reflected, the line need only have half the number of sections required for the corresponding line shown in Fig. 4. The output signal of valve V5 is applied to the valve V6 of the next stage through a capacitor 15 of high capacity compared with the capacitors of the delay line. In the circuit of Fig. 6 the delay line is terminated at either end by matched resistances R, the direct pulse and the delayed pulse being applied respectively to the grids of cathode-follower stages V10, V11. The output circuits of V10 and V11 are connected in series by balancing resistors R1, R2 and a potentiometer P is used to pick up the correct fraction of the output signal which is the sum of the outputs of V10 and V11. At very high frequencies the delay lines may comprise lengths of transmission line and waveguides may be used at microwave frequencies.

    58.
    发明专利
    未知

    公开(公告)号：DE1017656B

    公开(公告)日：1957-10-17

    申请号：DER0008838

    申请日：1952-04-17

    Applicant: SOC NOUVELLE OUTIL RBV RADIO

    IPC: H04N11/08

    Abstract: 711,880. Colour television. RADIO-INDUSTRIE. April 17, 1952 [April 17, 1951], No. 9714/52. Class 40 (3) A three-colour line-sequential colour television employs four-fold interlacing of the scanning lines ; thus in the first partial frame I, Fig. 2, successive lines are scanned in a sequence red, blue, green, in the second partial frame II successive lines are scanned in the same order with, however, red lines displaced by 1¢ lines of the partial frames, in the third partial frame III the red lines are again displaced by a further line of the partial frames, and in the fourth partial frame IV, the red lines are displaced by a further 1¢ lines of the partial frames, while when returning to the first partial frame a further displacement of 2“ lines takes place. The transmitter comprises three camera tubes 1, 2, 3 rendered respectively responsive to red, blue and green partial images by means of filters 4, 5 and 6. Switching potentials developed in a circuit 12 controlled from the time-base 13 are applied to gating circuits 14, 15 and 16 to render them successively operative at line frequency to pass the video signal outputs of the respective camera tubes to an output circuit. The receiver, Fig. 10 (not shown), comprises three cathode-ray tubes having associated colour filters and means for optically combing the pictures produced on the screens, the incoming video signal being switched in sequence at line frequency, by means of gating circuits similar to those shown at the transmitter, to the three cathode-ray tubes. It is arranged that each partial frame commences with a red line ; to achieve this it will be seen that corresponding synchronizing signals must be delayed in succession by 1¢, ¥, 1¢ and 2“ lines of the partial fields, this being done by a "slipping" process involving the increase or decrease of the line period during the frame blanking intervals. The transmitter comprises a pulse generator operating at eight times the normal line frequency, the normal line-synchronizing pulses being derived by a frequency divider dividing by eight an input taken from the pulse generator. However, during each frame blanking period this frequency divider is rendered inoperative and is effectively replaced by an auxiliary divider having a division ratio of either nine or seven. By means of control signals generated by suitable counting circuits this latter divider remains operative for periods respectively corresponding to 12, 6, 12 and 18 pulses from the pulse generator during successive frame blanking intervals ; after this the auxiliary divider is cut off and the first divider rendered operative. Thus a displacement of the line synchronizing pulses by 1¢, ¥, 1¢ and 2“ lines in successive frame blanking intervals is effected.

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