US2013103A - Short wave receiving circuit - Google Patents

Description

Sept. 3, 1935. I w. LUDENIA 2,013,103

SHORT WAVE RECEIVING CIRCUIT I Filed Aug. 23, 1950 g," Q d in Q5 'INVENTOR WERNER LUDEMA" ATTORNEY Patented Sept. 3, 1935 PAT NroFricE 2,013,103 snoar WAVE RECEIVING oracnrr Werner Ludenia, Berlin, Germany, assignor to Radio Corporation of America, acorporation of Delaware i Application August 23, 1920,. Serial No. 477,344

Germany December 10, 1929 10 Claims. (01. 250-20) There "are known short-wave receiving circuits wherein there is used an electronic tube or electron discharge device in the so-called Barkhausen-Kurz connection; i. e. with a grid or control electrode impressed with a high positive potential and a plate having a lower potential and whereby one-half of a dipole is connected to the grid or the cathode.

By experimental have found that it is advantageous to usel instead of a dipole an antenna which is tuned to M2. To one end or to both ends of this antennaI connect the plate of one tube each. The potential supply to the plate of the tube is accomplished from the electrical mid-point of theantenna.

As required by the revised statutes, my invention is defined in the appended claims. However,it may bestbe understood both as to its- 0 wherein the anode of an electron discharge device is maintainedat a relatively negative potential, and has connected directly theretoa half wave length conductor to whose'voltage nodal point there is supplied anode potential,

1 Figure2illustrates a pair of electrondischarge devices having cathodes energized as in Figure 1 and having a half wave length conductor connected to the anodes of the tubes such that the tubes'act inpushpull fashion, and, A Figure '3 illustrates an arrangement similar to that shown in Figure 1 wherein the lead-in wire to the anode forms apart of the antenna.

In Figure 1 there is the antenna a which is connected at one endwith the anode or plate ofelectron discharge device or tube 1'. To the electricalmid-point p of the antenna is connected the potential for theplate through a choke coil' 03. The end'q of the antenna is left open ended or electrically free.

Good reception on ultra short wave lengths riations in amplitude of the locally generated waves will in turn cause marked changes in anode currentflow corresponding to the modulation of the transmitted Waves, These relatively low frequency variations may be taken from the plate circuit by means of a suitable transformer 2 amplifiedb-y a suitable amplifier 4 and translated by any suitable translating device such as the illustrated telephone ii.

In Figure 2 both ends of the antenna .a are connected with a plate of each of the tubes 1'1 and 72 which act in pushpull fashion. The potential supply to the plates is likewise accom plished through a choke d.

The electron discharge devices shown in Figure 2 are connected and act in pushpull fashion since the extremities of antenna a are always at voltage maximums of opposite polarity. Here also operation of translating device 6 coupled to the anode supplycircuit through-an amplifier i and transformer 2 may be obtained by adjustment of the potentials such that the system is on the verge of oscillation. Signalling waves will produce variations in anode energy flow as a result of which there will be modulation indication in the translating device 6.

It is suitable to use also a tube with standard base in the manner that a part of the antenna is" formed by the lead-in wires of the tube capacitatively coupled with one another. In Figure 3,

R isthe tube, whose lead-in wires form a part of the antenna a. The translatingdevice 6 is here shown as directly connected in the anode supply lead. The overall length a should, of course, be one-half wave length. The length of anode lead between the anode and voltage nodal point]? should be chosen such that the overall length a, of the antenna is one-half wave length and such that point P is at a voltage nodal or current maximum point.

Arrangements according to the present invention are especially suitable for the directional reception of short waves whereby the minimum of reception isobt ained when the arrangement pointswith its'longitudinal axis towards the transmitting station, but the maximum of tree. ceptio'n thetransversal position; or, in a direction at right angles to the line between the receiver and transmitter.

Although the systems described are particularly useful for reception of short waves, it is clear that they may also be used for the transmission of signals on electromagnetic wave energy. In that event, translating device 6 may be replaced by a source of modulating energy which in turn is amplified by a suitable amplifier such as amplifier 4 and fed to the anode circuit of the devices.

I claim:

1. In combination, an electron discharge device having a cathode, an anode and a control electrode, energy means in circuit with said cathode for maintaining said control electrode at a relatively positive potential and said anode at a lower potential with respect to said cathode, a half wave length conductor directly connected to said anode and a connection from the electrical midpoint of said half wave length conductor to said energy means, whereby said anode is maintained at suitable potential through said connection and conductor.

2. An ultra short wave length receiving system comprising an electron discharge device having a cathode, an anode and a control electrode, a source of energy in circuit with said cathode for maintaining said control electrode at a positive potential with respect to said cathode, a half wave length antenna directly connected to said anode, another source of energy in circuit with said cathode and a connection between said last source and the midpoint of said half wave antenna for maintaining said anode at a negative potential with respect to said cathode, and a utilization circuit coupled to said connection.

3. Apparatus as defined in claim 2 including a high frequency choke coil in said connection, and a transformer for coupling to said utilization circuit.

4. In ultra short wave length electrical apparatus, the combination with a pair of electron discharge devices having anodes, cathodes, and control electrodes, and energy means for maintaining said anodes and control electrodes at relatively negative and highly positive potentials, respectively, with respect to their respective cathodes, of a half wave length conductor directly connected to the anodes of the electron discharge devices, and a connection from substantially the midpoint of said half wave length conductor to said energy means.

5. In combination, a plurality of electron discharge devices having anode, cathode and control electrodes, connections between the respective corresponding electrodes of said devices,,the connection between said anodes comprising an energy collector, a source of energy connected to said control electrodes of said devices for maintaining same at a positive potential relative to their respective cathodes, another source of energy, a connection including a high frequency choke coil extending between said last source and the electrical midpoint of said energy collector for maintaining said anodes at a lower potential than that on said control electrodes relative to their respective cathodes, and a utilization device eleotromagnetically coupled to said last connection.

6. In ultra short wave length electrical apparatus, the combination of a plurality of electron discharge devices having anodes, cathodes and control electrodes, a source of energy having its positive terminal connected to said control electrodes, another source of energy, a half wave length conductor connected directly to the anodes of said electron discharge devices, and a connection between the negative terminal of said last source and the midpoint of said half wave length conductor for supplying potentials to the anodes of said devices.

7. In ultra short wave length electrical apparatus, a pair of electron discharge devices having anode, cathode and control electrodes, connections between said respective corresponding electrodes of said devices, the connection between said anodes comprising a half wave length conductor, a source of energy connected to the control electrodes of said devices for maintaining same at a positive potential relative to the respective cathodes, a source of energy,and a connection between said last source and the midpoint of said half wave length conductor for maintaining said anodes at a potential lower than that on said control electrodes relative to their respective cathodes, and a relatively low frequency circuit coupled to said last connection.

8. In high frequency apparatus, an electron discharge device having a cathode, an anode and a control electrode, a source of direct current potential directly connected to said control electrode for maintaining same at a positive potential with respect to said cathode, a half wave length conductor connected to said anode, another source of direct current potential and a connection from said last source to said half wave length conductor for maintaining said anode at a relatively negative potential with respect to said cathode, said half wave length conductor being arranged to include as a portion thereof the length of the lead-in structure to the anode, and a relatively low frequency circuit coupled to said connection.

9. An ultra short wave length receiving system comprising an electron discharge device having an anode, cathode, and a grid, means for maintaining said grid at a positive potential and said anode at a much lower potential with respect to said cathode, an antenna having one end connected to said anode, a supply lead from the electrical midpoint of said antenna to said means for supplying said anode with potential, an inductance in said supply lead, and an output circuit coupled to said anode supply lead.

10. In combination, an electron discharge device having an anode, cathode, and control electrode, means for maintaining said control electrode at a positive potential with respect to said cathode, and said anode at a potential much less than said control electrode potential, an energy collector in circuit with said anode and a connection from a voltage nodal point on said collector to said means, whereby said anode is supplied with potential through said connection and collector.

1 WERNER LUDENIA.

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