US2434116A

US2434116A - Ultra high frequency resonator device

Info

Publication number: US2434116A
Application number: US570257A
Authority: US
Inventors: Elmer D Mcarthur
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1944-12-29
Filing date: 1944-12-29
Publication date: 1948-01-06
Anticipated expiration: 1965-01-06
Also published as: GB614000A

Description

Jan. 6, 1948. E. D. MCARTHUR I 2,434,116

ULTRA HIGH FREQUENCY RESONATOR DEVICE Filed Dec. 29, 1944 a2 34 Flgl. ,8 29 ,9 2/ z Y Z8 /0 2a 26 50 5 I r 23 38 ,g a 3 be as Inventor:

Elmer D. MCATthUT,

by fl U W His Attorney.

Patented Jan. 6, 1 948 UNITED STATES PATENT OFFICE ULTRA HIGH FREQUENCY RESONATOR VICE Elmer ll). McArthur, Schenectady, N. Y., assignor to General Electric Company, a corporation of New York 7 Claims.

My invention relates to ultra high frequency circuits employing cavity resonators and is concerned primarily with the provision of new and improved circuits of this type having high power output.

It is an object of my invention to provide new and improved ultra high frequency circuits of the cavity resonator type which utilize standing waves of differing patterns in the resonator.

It is a further object of m invention to provide a new and improved ultra high frequency oscillator having high frequency stability, as well as high power output.

It is a still further object of my invention to provide new and improved ultra high frequency circuits employing a plurality of electronic tubes in such a way that all contribute to a common power output system.

It is a still further object of my invention to provide new and improved push-pull ultra high frequency circuits.

In accordance with my invention, I provide improved ultra high frequency circuits which employ two cavity resonators separated by the control grids of a plurality of electronic tubes and, by selective energization of one of the cavity resonators, establish a standing Wave pattern in the resonators of a desired type, the tubes being operated either in push-pull or in parallel and all contributing to a common power output system. In one of its aspects, the invention contemplates the use, in an ultra high frequency oscillator, of a plurality of electronic tubes operating in parallel to provide increased frequency stability, as well as relatively large power output.

For a better understanding of my invention, reference may be had to the folio-wing description taken in connection with the accompanying drawing and its scope will be pointed out in the appended claims. Fig. 1 diagrammatically illustrates an embodiment of my invention as applied to an ultra high frequency amplifier; Fig. 2 is a diagrammatic illustration of an embodiment of the invention as applied to an ultra high freinvention as applied to an ultra high frequency amplifier which comprises a pair of cavity resonators defined by a hollow conductive cylinder I having a transverse conductive wall 2 located within the cylinder approximately at its mid point. The transverse metallic wall has a pair of apertures 3, 4 in which are supported a pair of electronic discharge devices 5, B. Each of the electron discharge devices 5, 6 includes an anode "I, a cathode 8 and a control grid or electrode 9. The control grid, which affords a continuous span across the associated aperture, is supported by transverse metallic disk I0 which is maintained in position in the apertures 3, 4 by any suitable means illustrated conventionally as the spring finger arrangement I I.

A pair of conductors I 2, I3 are conductively connected to the anodes of the devices 5, 6, respectively, and extend in a direction parallel with the axis of the conductive cylinder I and from the anodes of these devices to the region outside of the cylinder I, A pair of tubular conductors I4, I connected to the cathodes 8 of the devices 5, 6, respectively, for high frequency alternating currents are arranged parallel to the axis of the cylinder I and extend in a direction opposite to that of the conductors I2, I3. Moreover, conductors I4, I5 preferably are substantially coaxially aligned, respectively, with the conductors quency oscillator; Figs. 3-5 show the'variations in standing wave patterns which may be obtained in cavity resonators similar to those employed in the systems of Figs. 1 and 2 by variation in the number of electronic tubes employed and different methods of energization; and Fig. 6 diagrammatically illustrates a modification of the invention employin an alternative form of cavity resonator.

Referring particularly to Fig. 1 of the accompanying drawing, I have there illustrated the I2, I3. The cathodes 8 preferably are insulated from conductors I4, I5 for unidirectional currents, and unidirectional operating potentials, as well as currents for heatin filaments (not shown) for the devices 5, 6, are supplied over the lead-in conductors I6, I! which extend through the tubular conductors I4, I5. The ends of the conductors I2--I5 remote from the transverse wall 2 are supported in alignment with each other and with the electrodes of the devices 5, 6 by a pair of end walls I8, I9.

The construction thus described defines a pair of cavity resonators of the multi-conductor type, the cylinder I forming the outer conductor of each of the resonators, the conductors I2, I3 constituting the inner conductors of a first cavity resonator coupled with the space between the anode and grid of the devices 5, 6, and the conductors I4, I5 constituting the inner conductors of a second cavity resonator coupled with the cathode-grid regions of the devices 5, 6. The

dimensions of these two cavity resonators may be adjusted by means of a pair of tuning plungers or pistons 20, 2|. The piston 20 carries contact fingers 22 engaging the inner surface of cylinder I and

contact fingers

23, 24 engaging, respectively, the outer surfaces of conductors [2, I3. Tuning piston 2| similarly is provided with contact fingers 25-21 in conductive engagement, respectively, with the inner surface of cylinder I and the outer surface of conductor I4 and the outer surface of conductor l5. Adjustment of the positions of the plungers 2E1, 2! for varying the dimensions of the cavity resonators may be made by means of the

rods

28, 29 attached to these tuning pistons.

In order that the ultra high frequency system of Fig. 1 may utilize the electron discharge devices 5, 6 in push-pull arrangement for amplification of signals, a pair of input electrodes are provided and are illustrated as of the capacitive type. These electrodes comprise plates 30, 3| attached, respectively, to the

inner conductors

32, 33 of a pair of concentric transmission lines having

outer conductors

34, 35. Means are also provided for the extraction of amplified signals from the cavity resonator coupled with the anode-grid region of the discharge devices 5, 6 and are illustrated as comprising a coupling loop 35 having one of its ends attached to the plunger 20 and its other end connected to a conductor 31 which is centrally positioned within a tubular conductor 38 forming therewith an output transmission line of the coaxial conductor type Alternatively, the input coupling means may be of the induction type rather than the capacitive type and may be similar in form to the output coupling loop 35.

Fig. 2 illustrates the circuit, arrangement of an ultra high frequency oscillator in which the input electrodes shown in Fig. l are omitted and feedback means in the form of a coupling loop 35 linking the electromagnetic waves within the anode-grid cavity and the cathode-grid cavity is provided. In all other respects, the structure of Fig. 2 is the same as that of Fig. l.

The multi-tube circuits shown in Figs. 1 and 2 take advantage of the fact that many standing wave patterns are possible in a transmission linein addition to that of the conventional coaxial system which has cylindrical symmetry; Fig. 3 illustrates the field pattern which exists in the cavity resonators of the circuit ofFig. 1 when the cathode-grid resonator is energized from a double-end feed or input source by means of the probes 33, Si or some equivalent energizing means. Electronic tubes 5, 6, with this feeding arrangement, operate in push-pull to excit the anode-grid cavity resonators and establish the same electromagnetic wave pattern in this resonator. The dimensions of each of the resonators are adjusted by means of the plungers 20, El to resonate at the input frequency. The output loop 38 preferably is located at a point of strong magnetic field in the anode-grid cavity between the conductors l2, l3 and linked with the electromagnetic fields at that point. With this configuration of the cavities and arrangement of the conductors, each of the tubes 5, 6

contributes to the common power output system with a resultant increase in power output and stability of the system.

The field pattern of Fig. 4 is that established within the cathode-grid cavity resonator when the input probes 3%, 3i supplied with signals of the'same phase or when a single probe is used so that the electronic tubes 5 and 5 operate in parallel. It is, of course, apparent that the operatingfrequency of the system, when operating in parallel, is dilierent from that when'operatingin push-pull, since the wave patternand mode of operation of the multi-conductor resonator require energy of a different frequency and excitation to operate with this wave pattern. While both the field patterns of Figs. 3 and 4 show the use of a pair of probes for exciting the cavities, it is apparent that an input or driving loop similar to that of the output loop 33 may be employed in the cathode-grid resonator to excite the resonator, especially when the system is operated from a single-ended feed line.

It is apparent that the ultra high frequency circuits of my invention may employ more than two electronic tubes and more than two inner conductors in each of the cavity resonators. The field pattern of Fig. 5 illustrates the configuration, of the electronic waves within a cavity resonator which employs four symmetrically placed electronic devices which are operating in push-pull. Each of the devices in this arrangement contributes its full power to the output circuits of the system resulting in increased output and frequency stability.

My invention is applicable likewise to systems in which the cavity resonator-forming conductive member may have configurations other than. that shown in Fig. 1. Fig. 6 illustrates one such variation in which the outer conductive member 48 of the cavity resonator structure is elliptical in form. In this instance, the inner conductive rods 4|, 42, which are contained in the input cavity resonator for example and are connected to the cathodes of the electron discharge devices, are located at the foci of the ellipse. The conductors 4|, 42 may likewise be elliptical in configuration. The cavity resonator formed bythe members 4l42. is energized by an input coupling loop 43 similar to loop 36 of Fig. 1 and which may extend through the tuning piston of the cavity resonator. While the operation of such a system is essentially the same as that of the previously described modifications, the use of the elliptical members lends to stability and ease in maintaining the system operating in the push-pull mode.

While I have shown and described my invention as applied to particular systems embodying various devices diagrammatically shown, it will be obvious tothose skilled in the art that changes and modifications may be made without depart-- ing from my invention and that Itherefore contemplate in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of my invention.

What I claim as new and desire to secur by Letters Patent or" the United States is:

1. An ultra high frequency system comprising a hollow conductive cylinder, a transverse wall located within said cylinder having a plurality of apertures, an electron discharge device extending through each of said apertures, each of said devices having a grid constituting a conductive extension of said wall across the associated aperture and an anode and a cathode disposed on opposite sides of said wall, conductors connected to the anodes of said devices extending longitudinally within said cylinder in parallel relation to the axis thereof and constituting with said cylinder a first cavity resonator on one sideof said transverse wall, conductors connected to the cathodes of said devices extending longitudinally within said cylinder in parallel relation to the axis thereof and constituting with said cylinder a second cavity resonator on the opposite side of said transverse wall from said first cavity resonator, and conductive means constituting adjustable end walls for said resonators.

2; A resonator device comprising a grid-cathode resonator and a grid-anode resonator, a hollow conductive cylinder constituting a common outer wall of said resonators, a transverse wall-within said cylinder having a plurality of apertures and constituting a common end wall of said resonators, a plurality of conductors on each side of said transverse wall extending longitudinally within said cylinder and parallel thereto constituting inner members of said resonators, a plurality of electron discharge devices extending one through each of said apertures, each of said devices having a grid conductively connected to said transverse wall, and a cathode and an anode positioned respectively in said grid-cathode and grid-anode resonators and conductively coupled each to one of said conductors, and push-pull input electrodes coupled to said grid-cathode resonator for exciting said grid-cathode resonator in push-pull pattern.

3. A device as in claim 2 in which said input electrodes are adapted to be energized in phase opposition.

4. A device as in claim 2 in which said input electrodes are adapted to excite said grid-cathode resonator with a signal to be amplified, and including output means coupled to said grid-anode resonator for deriving an amplified signal therefrom.

5. An ultra high frequency device comprising a hollow conductive cylinder, a transverse wall located within the cylinder and having a plurality of apertures, a plurality of electron discharge devices extending one through each of said apertures, each of said devices having a grid constituting a. conductive extension of said wall across said each of said apertures, said devices having anodes disposed on one side of said transverse wall and cathodes on the opposite side thereof, conductors connected to the anodes of said devices extending longitudinally within said cylinder in a direction parallel to the axis thereof and constituting with said cylinder a first cavity resonator on one side of said transverse wall, conductors connected to the cathodes of said devices and extending longitudinally within said cylinder in a direction parallel to the axis thereof and constituting with said cylinder a sec-- 0nd cavity resonator on the opposite side of said transverse wall from said first cavity resonator, and push-pull input electrodes coupled to said second cavity resonator for exciting the same in push-pull pattern.

6. A device as in claim 5 in which said input electrodes are adapted to be energized in phase opposition.

7. A device as in claim 5 including conductive means constituting adjustable end walls for said first and second cavity resonators.

ELMER. D. McARTHUR.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,284,405 McArthur May 26, 1942 2,381,320 Tawney Aug. 7, 1945 2,400,753 Haefi May 21, 1946 2,408,927 Gurewitsch Oct. 8, 1946