Patent GB-419137-A (GB)
Title: Wireless receiving systems
IPC: H01J21/18
Filed: 1933-03-01
Abstract: 419,137. Thermionic valves; receiving systems. JENSEN, C. A. S., 56, Hyldegaardsvej, Charlottenlund, Copenhagen. March 1, 1933, No. 6300. Convention date, March 1, 1932. [Classes 39 (i) and 40 (v).] A receiving system comprises a thermionic valve for amplifying or detecting high-frequency currents having a cathode, an anode and an intermediate electrode comprising one or more flat conducting members parallel or oblique to the electron path and a coil adapted to produce a magnetic field deflecting the electron beam, and this coil is inserted in the input circuit of the valve. A control grid may in addition be inserted in the valve. The intermediate electrode may be biassed positively, so as to collect electrons, or negatively, so as to reflect them. In one form, Fig. 5, the coil e is inserted in a receiving circuit L C, and the anode a receives a current, the frequency of which is double that of the incoming signals. The intermediate electrode d is positively biassed from a source B. If the component members of the electrode d are arranged obliquely to the beam, or if the coil carries a continuous current in addition to the input, the frequency will be unaltered. The anode of the valve may be constituted by the deflecting coil, and has a lead at each end for the input, and a centre tap for the output. In a modification, Fig. 8, the anode circuit is coupled by an inductance L1 to a circuit L2, C2 connected to the grid which thus supports the controlling effect of the anode coil a. The control may be supplemented by connecting the intermediate electrode to a positive voltage through a biassing resistance. In a modification, the electrode is biassed negatively and a further positively biassed grid is arranged near it. In another modification, the grid is placed between the intermediate electrode and the anode, and is connected to one plate of a differential condenser, the second plate of which is connected to the cathode and the common plate to the intermediate electrode. If the output is taken from one end of the anode coil a continuous deflecting current may be dispensed with. Fig. 14 shows a construction of valve in which the intermediate electrode de forming a helical surface, such as that made by winding a flat strip, is used also as the deflecting coil. In another form, the coil is split into two seriesconnected parts arranged one at each side of the anode with their axes at right-angles thereto. The intermediate electrode may comprise two sets of bars lying on annular surfaces, one inside the other, and radially aligned or staggered with respect to each other. The intermediate electrode may be biassed negatively and coupled to the anode circuit, and an additional grid, which may be positively biassed through a resistance, provided to collect the reflected electrons. According to the Specification as open to inspection under Sect. 91, the valve may be used in generating or low-frequency amplifying circuits. In Fig. 14 (Cancelled), the anode coil a is inserted in a tuned circuit L, C, to which the anode circuit is coupled by a coil L3. The grid and anode are coupled by coils L1, L2 and the grid circuit is timed by condenser C2. A modulator circuit comprises also an input transformer connected to a grid in the valve. In a modification, the anode circuit is modulated whilst the anode coil is fed with continuouscurrent to avoid frequency doubling. In another modification, the input from an oscillator is applied to the grid of the valve and modulation is effected in the anode coil circuit. In a receiving circuit the input may be applied to a grid and the deflecting coil, distinct from the anode, included in a circuit coupled to the input circuit. The anode coil may be split into two parts and the intermediate electrode may consist of radial longitudinal fins secured together by rings. Or the anode and the intermediate electrode may consist, as shown in Fig. 25 (Cancelled), of alternately connected segments a, d of one cylinder, with insulating or negatively biassed metallic shields f between each anode and intermediate electrode segment and the next pair. This subject-matter does not appear in the Specification as accepted.