US2054252A - Device for the production of oscillations - Google Patents

Device for the production of oscillations Download PDF

Info

Publication number
US2054252A
US2054252A US735390A US73539034A US2054252A US 2054252 A US2054252 A US 2054252A US 735390 A US735390 A US 735390A US 73539034 A US73539034 A US 73539034A US 2054252 A US2054252 A US 2054252A
Authority
US
United States
Prior art keywords
grid
cathode
acceleration
acceleration grid
potential
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US735390A
Other languages
English (en)
Inventor
Hausser Isolde
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Application granted granted Critical
Publication of US2054252A publication Critical patent/US2054252A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03B—GENERATION OF OSCILLATIONS, DIRECTLY OR BY FREQUENCY-CHANGING, BY CIRCUITS EMPLOYING ACTIVE ELEMENTS WHICH OPERATE IN A NON-SWITCHING MANNER; GENERATION OF NOISE BY SUCH CIRCUITS
    • H03B9/00—Generation of oscillations using transit-time effects
    • H03B9/01—Generation of oscillations using transit-time effects using discharge tubes
    • H03B9/02—Generation of oscillations using transit-time effects using discharge tubes using a retarding-field tube
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J19/00—Details of vacuum tubes of the types covered by group H01J21/00
    • H01J19/02—Electron-emitting electrodes; Cathodes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J25/00—Transit-time tubes, e.g. klystrons, travelling-wave tubes, magnetrons
    • H01J25/68—Tubes specially designed to act as oscillator with positive grid and retarding field, e.g. for Barkhausen-Kurz oscillators
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2893/00—Discharge tubes and lamps
    • H01J2893/0001—Electrodes and electrode systems suitable for discharge tubes or lamps

Definitions

  • My invention relates to a device for the production of oscillations, and more particularly for the production of very short electric waves by means of highly exhausted vacuum valves having a cathode, a grid and a plate electrode and in which a further, auxiliary electrode is arranged between the cathode and the grid and is so positioned, formed and charged that it screens the grid wholly or partly from the electrons emitted by the cathode.
  • the invention has for its object to eliminate the above undesired additional action to which is partly due the extremely low efiiciency of the usual transmitter valves for short waves.
  • the grid which is to fulfill several conditions inconsistent with one another, i. e., on the one hand, it must be impressed with a high acceleration voltage so as to attain great speeds of electrons and, on the other hand, should not be impressed with a high potential in order to prevent too great losses between cathode and control gridis so to say subdivided into two grids: i. e. a grid with high positive potential which will be denoted hereinafter as acceleration grid and a second grid with low or even negative potential with respect to the heated cathode, the second grid being placed between the acceleration grid and the cathode and representing the control grid proper.
  • This control grid which is inserted according to the invention between the heated cathode and the acceleration grid must not only be correspondingly arranged as regards space but must also be suitably designed geometrically in order to obtain the desired result:
  • the rods or wires of the acceleration grid must be located, viewed from the heated filament of the heated cathode, behind the rods or wires of the control grid.
  • the stream of electrons emitted by the cathode will be then divided into individual small streams which pass by the rods or wires of the acceleration grid.
  • the control grid acts in a screen-like manner. The electrons flow, therefore, with great velocity through the interstices between the acceleration grid elements in accordance with high acceleration potentials.
  • the voltage effect of the acceleration grid past the control grid bars and toward the cathode must be as great as possible in order that the electrons may attain great velocities on their way from the cathode to the acceleration grid, in order to maintain the magnitude of the required acceleration voltages within reasonable values.
  • the heated filaments of the cathode are preferably arranged elosely in front of the interstices between the grid rod elements. Consequently, the rods of the acceleration grid must be laterally protected by the elements of the control grid, i. e., the latter must form so to say a roof for the former.
  • the transmitter valve provided in the abovedescribed manner with a control grid for deviating the electrons into the interstices between the acceleration grid may be employedin various connections.
  • the plate in the form of a disc, and serving as fourth electrode and lying beyond the acceleration grid which plate in the case of a concentric arrangement of electrodes may also be replaced by a cylinder, may be caused to act as anode, i. e., it may be impressed with a high positive potential.
  • Such a connection which is usually employed for the production of waves of considerable length could not be utilized for short waves to the desired extent.
  • the novel valve has the advantage, that the acceleration grid for the electrons operates at zero current, i. e. without losses, owing to the screening effect of the control grid.
  • the plate may be impressed with a positive voltage which has a value below that of the acceleration grid as is the case in the known dynatron connections. Also in this case an advantage is ob tained in that the acceleration electrode works nearly at zero current owing to the screening effect of the control grid.
  • Fig. 1 represents in diagramdrically shaped and surrounds the concentrically reach the zone of zero potential.
  • the heated filaments of the cathode are denoted by K, the acceleration grid by G2, the control grid by G1 .andthe plate electrode by A.
  • the relative arrangement of the electrodesand their geometrical design are shown in semi-diagrammatic fashion.
  • the individual broader strips of the control grid which, for instance, have an angular form so that they partly embrace the rods or wires of the acceleration grid.
  • the heated filaments of the cathode are positioned in the interstices between the control grid strips, so that all travelling distances become small.
  • the control grid maybe impressed with respect to the cathode for instance with a negative potential of 500 volts, the acceleration grid with .a positive potenial of 4000 volts and finally the plate A serving as retarding electrode may in turn be impressed with a negative potential with respect to the cathode, i. e., with
  • the electrons the static fields through the interstices between the control grid G1 and those between the acceleration grid G2 into the space between the acceleration grid G2 and the plate electrode A. In this space they meet a strong field owing to the strong negative charge of the plate electrode.
  • the speed of the electrons is reduced to zero owing to the retarding effect of the plate field as soon as they 7
  • the location of this zone is identical with that of plate A if'the latter has'the potential zero with respect to the cathode and is located further toward the acceleration grid G2 if the potential of the plate, as
  • rhythmical reversal of such a cloud of electrons causes, for instance, at the acceleration grid G2 fluctuations of voltage in the same rhythm, particularly when the oscillation circuit connected to the acceleration grid and the cathode or also to the acceleration grid and plate electrode is substantially in resonance with the movements of the cloud of electrons, i. e., when the duration of an oscillation of the oscillation circuit is approximately equal to the time which the cloud of electronsrequires to move forward and return.
  • a pair of parallel conductors is'preferably employed, one end of which pairis respectively connected to the appertaining electrodes of the valve and the other end is bridged tween the cathode and control grid G1.
  • a blocking condenser capable of being'shifted along the parallel conductors for the purpose of tuning.
  • these parallel conductors are designated by L1L1 and LzLz, and the appertaining condensers are denoted with C1 and C2 respectively.
  • the direct-current connections lead to the blocking condensers by way of reactors Dr. Also the other direct current connections lead as usual to the cathode and retarding electrode through reactors Dr.
  • Both oscillation circuits formed of the parallel conductors as main part are coupled by the common inner capacity of the valves be-
  • the parallel circuit L1L1 is closed through said capacity.
  • the other circuit L2L2 is series-connected with two capacities, i. e., with the above-mentioned capacity between the cathode and the control grid and with the other between the control grid G1 and acceleration grid G2, so that the system L1L1 is coupled with a portion of the capacity of circuit L2L2.
  • the alternating voltages between the acceleration grid and cathode .and between the control grid and cathode are in phase.
  • the oscillation process is as follows: In the positive phase of both grid alternating potentials the electrons which are so accelerated by the strong field as to obtain a high speed, are forced in the above-mentioned manner through the grid interstices into the space between the acceleration electrode G2 and plate electrode A and .are here retarded to the velocity zero.
  • the electrons In the negative phase of both grid alternating potentials the electrons, on the one hand, change their direction of motion in the retarding space and impinge upon the rods or wires of the acceleration grid G2 which acts here as anode; on the other hand, since, as above stated, the alternating potential applied to the control grid also passes through the negative phase, the flow of electrons from the cathode through the interstices of the grid is considerably weakened in the direction toward the retarding electrode so that an interference by newly emitted electrons with the cloud of electrons returning from the retarding field to the acceleration grid is avoided.
  • the negative resistance of the valve required for setting up the oscillations, is brought about by the fact that the electrons in the positive phase of the alternating potential pass by the acceleration grid at a very high speed and impinge upon the grid as anode current only after they have been retarded and have changed their direction and at a time when the alternating potential at this grid just passes through the negative phase.
  • connection may also be, of course, employed for a concentric arrangement of the electrodes as shown in Fig. 2.
  • Arrangement for producing electrical oscillations including a highly evacuated envelop containing a cathode, a plate, an acceleration grid interposed between said cathode and plate and a control grid'interposed between said cathode and acceleration grid, circuit connections for charging said acceleration grid highly positive with respect to said cathode and charging said control grid with respect to said cathode at a potential lower than said acceleration grid potential and said plate at a potential not higher than neutral with respect to said cathode, a tunable oscillatory circuit including said acceleration grid, and means for imparting oscillations to said control grid which are substantially in phase with the oscillations prevailing at said acceleration grid.
  • Arrangement for producing electrical oscillations including a highly evacuated envelop containing a cathode, a plate, an acceleration grid interposed between said cathode and plate and a control grid interposed between said cathode and acceleration grid, circuit connections for charging said acceleration grid highly positive with respect to said cathode and charging said control grid with respect to said cathode at a potential lower than said acceleration grid potential and said plate at a potential not higher than neutral with respect tosaid cathode, a tunable oscillatory circuit including said acceleration grid, and means for imparting oscillations to said control grid which are substantially in phase with the oscillations prevailing at said acceleration grid, the grid elements of said acceleration grid being respectively in alinement with the control grid elements with respect to the direction of the electron stream emitted from the cathode, so that the acceleration grid is located in the electron shadow produced by said control grid.
  • Arrangement for producing electrical oscillations including a highly evacuated envelop containing a cathode, a plate, an acceleration grid interposed between said cathode and plate and a control grid interposed between said cathode and acceleration grid, circuit connections for charging said acceleration grid highly positive with respect to said cathode and charging said control grid with respect to said cathode at a potential lower than said acceleration grid potential and said plate at a potential not higher than neutral with respect to said cathode, a tunable oscillatory circuit including said acceleration grid, and means for imparting oscillations to said control grid which are substantially in phase with the oscillations prevailing at said acceleration grid, the grid elements of said acceleration grid being respectively in alinement with the control grid elements with respect to the direction of the electron stream emitted from the cathode, and being at least partly surrounded by said control grid elements, so that the acceleration grid is located in the electron shadow produced by said control grid.
  • Arrangement for producing electrical oscillations including a highly evacuated envelop containing a cathode, a plate, an acceleration grid interposed between said cathode and plate and a control grid interposed between said cathode and acceleration grid, circuit connections for charging said acceleration grid highly positive with respect to said cathode and charging said control grid with respect to said cathode at a potential lower than said acceleration grid potential and said plate at a potential not higher than neutral with respect to said cathode, a tunable oscillatory circuit including said acceleration grid, and means for imparting oscillations to said control grid which are substantially in phase with the oscillations prevailing at said acceleration grid, the grid elements of said acceleration grid being respectively in alinement with the control grid elements with respect to the direction of the electron stream emitted from the cathode, so that the acceleration grid is located in the electron shadow produced by said control grid, said cathode consisting of a plurality of elements disposed in alinement with and close to the interstitial spaces between said control grid elements.
  • Arrangement for producing electrical oscillations including a highly evacuated envelop containing a cathode, a plate, an acceleration grid interposed between said cathode and plate and a control grid interposed between said cathode and acceleration grid, circuit connections for charging said acceleration grid highly positive with respect to said cathode and charging said control grid with respect tosaid cathode at a potential lower than said acceleration grid potential and said plate at a potential not higher than neutral with respect to said cathode, a tunable oscillatory circuit including said acceleration grid and said cathode, and a second tunable oscillating circuit including said cathode and said control grid, for imparting oscillations to said control grid which are substantially in phase with the oscillations prevailing at said acceleration grid.
  • Arrangement for producing electrical oscillations including a highly evacuated envelop containing a cathode, a plate, an acceleration grid interposed between said cathode and plate and a control grid interposed between said cathode and acceleration grid, circuit connections for charging said acceleration grid highly positive with respect to said cathode and charging said control grid with respect to said cathode at a potential lower than said acceleration grid potential and said plate at a potential not higher than neutral with respect to said cathode, a tunable oscillatory circuit including said acceleration grid, and means for imparting oscillations to said control grid which are substantially in phase with the oscillations prevailing at said acceleration grid, the distances between aforesaid electrodes and the potentials-applied to them being selected with respect to the frequencies of the oscillations imparted to said two grids such that accelerated electrons which are reversed in their original path by the prevailing plate potential strike the acceleration grid during the descending portion of each half period of the alternating electromotive force applied to said grid.

Landscapes

  • Electron Sources, Ion Sources (AREA)
US735390A 1933-07-17 1934-07-16 Device for the production of oscillations Expired - Lifetime US2054252A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE441341X 1933-07-17

Publications (1)

Publication Number Publication Date
US2054252A true US2054252A (en) 1936-09-15

Family

ID=6515753

Family Applications (1)

Application Number Title Priority Date Filing Date
US735390A Expired - Lifetime US2054252A (en) 1933-07-17 1934-07-16 Device for the production of oscillations

Country Status (3)

Country Link
US (1) US2054252A (enrdf_load_stackoverflow)
GB (1) GB441341A (enrdf_load_stackoverflow)
NL (1) NL46312C (enrdf_load_stackoverflow)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2977496A (en) * 1958-12-04 1961-03-28 Machlett Lab Inc Electrode structure for electron tubes
US3610996A (en) * 1968-05-21 1971-10-05 Beatrix A Elsasser Rusterholz High vacuum electron tube with magnetically isolated control electrode

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2977496A (en) * 1958-12-04 1961-03-28 Machlett Lab Inc Electrode structure for electron tubes
US3610996A (en) * 1968-05-21 1971-10-05 Beatrix A Elsasser Rusterholz High vacuum electron tube with magnetically isolated control electrode

Also Published As

Publication number Publication date
NL46312C (enrdf_load_stackoverflow)
GB441341A (en) 1936-01-17

Similar Documents

Publication Publication Date Title
US2220840A (en) Velocity modulation device
US2414121A (en) Electron device of the magnetron type
US2265337A (en) Pulse generating and pulse modulating system
US2245627A (en) Stabilization of frequency
US2103362A (en) Ultrahigh frequency magnetron oscillator
GB488094A (en) Improvements in or relating to thermionic valves and thermionic valve circuit arrangements for use on short waves
US1920863A (en) Amplification of radiant energy
US2468152A (en) Ultra high frequency apparatus of the cavity resonator type
US2237878A (en) Electron discharge device
US1613626A (en) Space discharge system
US2533401A (en) Coincidence detector of the focused rotary electron beam kind
US2202376A (en) Cathode ray tube detector circuits
US2605444A (en) Multichannel frequency selector and amplifier
US2054252A (en) Device for the production of oscillations
US2235497A (en) High frequency electron discharge device
US2266428A (en) Lateral deflection ultra high frequency tube
US2096817A (en) High frequency oscillator
US2411535A (en) High-frequency electron discharge apparatus
US2271716A (en) Electron discharge device
US2376707A (en) Space discharge device
US2243829A (en) Fixed plate variable capacity condenser
US1995175A (en) Electrical oscillation generator
US2293180A (en) Detector system of the velocity modulation type
US2762916A (en) Device comprising an electric discharge tube having a concentrated electron beam
GB548735A (en) Apparatus for electron discharge control