US2238262A

US2238262A - Ultra short wave apparatus

Info

Publication number: US2238262A
Application number: US225778A
Authority: US
Inventors: Jr William H Happe; Arthur K Wing
Original assignee: RCA Corp
Current assignee: RCA Corp
Priority date: 1938-08-19
Filing date: 1938-08-19
Publication date: 1941-04-15
Anticipated expiration: 1958-04-15
Also published as: GB531454A

Description

April 1941- w. H. HAPPE, JR, ETAL 2,238,262

ULTRA SHORT WAVE APPARATUS Filed Aug. 19, 1938 4 Sheets-Sheet 1 INVENTORS WILL/AM HHAPPEMR ANDAATHUR K. WING pril 15, 1941. w. H. HAP'PE, JR, Em 2,2 8,262

ULTRA SHORT WAVE APPARATUS Filed Aug. 19, 1938 4 Sheets-Sheet 2 INVENTORS ,l WILLIAM H'. HAPPEJA; ANDARTHUR K WING ATTORNEY.

April 1941. w. H. HAPPE, JR., ETAL 2,238,262

ULTRA SHORT WAVE APPARATUS Filed Aug. 19, 1938 4 Sheets-Sheet 3 INVENTORS W/LLIAM MHAPPEJR. BY 4/10 ARTHUR K. WING ORNEY.

April 15, 1941. w. H. HAPPE, JR, arm.

ULTRA SHORT WAVE APPARATUS Filed Aug. 19, 1938 4 Sheets-Sheet 4 INVENTORS WILLIAM H. HAPPEJR. AND ARTHUR K, WING ATTORNEY.

Patented Apr. 15, 1941 ULTRA SHORT WVAVE APPARATUS William H. Hapl e, Jr., Brooklyn, N. Y., and Arthur K. Wing, Chatham, N. J., assig'nors to Radio Corporation of America, a corporation 01' Delaware Application August 19, 1938, Serial No. 225,778

13 Claims.

This invention relates to improvements in ultra short wave apparatus. Various objects of the invention are: To provide novel mechanical arrangements for electron discharge device structures, which arrangements lend themselves especially for use with ultra short wave systems; to provide, within a single metallic container, a completely shielded multi-stage short wave system wherein the input and output circuits of at least one stage are isolated from each other; to provide a novel type of shielding socket for receiving the prongs of an electron discharge device; to provide a compact push-pull oscillator utilizing a single two-conductor transmission line and dispensing with tuned circuits having lumped or concentrated reactances; to enable variation of th coupling between a pair of two-conductor transmission lines in a simple and convenient manner, by making one of said lines rotatable.

One of the features of the present invention lies in the use of regenerative capacitors for the push-pull oscillator circuit, wherein each capacitor is composed of a pair of concentric conductors, the inner conductor of eachcapacitor forming part of one conductor of the transmission line.

Another feature of the invention comprises a novel socket arrangement having the general form of a metallic cylinder with a metallic shielding partition dividing the cylinder into two sections, one section accommodating the electron discharge device structure, while the other section accommodates the terminals for the prongs of the electron discharge device. Novel type prong receptacles are employed in the socket for effecting suitable by-passing of radio frequency energy directly at the prong.

These and other objects, features and their advantages will appear from a reading of the following description, which is accompanied by drawings, wherein:

Fig. 1 shows an elevation view of a novel type of completely shielded ultra short wave system of the invention. More particularly, the system of Fig. 1 illustrates a shielded push-pull oscillator arrangement which is variably coupled to an amplifier;

Figs. 2a to 21, inclusive, illustrate, in perspective, details of the various parts which go to make up the shielded system of Fig. 1. In effect, Figs. 2a to 2f combine to form an exploded view of the parts of Fig. 1;

Fig. 3 illustrates, very generally, an end crosssection view of the system of Fig. 1, taken along the lines 3--3;

Fig. 4a illustrates in more detail an end View of the novel socket of the invention shown in Fig. 2c, and shows the prong receptacles of the socket;

Fig. 4b illustrates an end view of the mount for the amplifier transmission line shown in Fig. 2b. The arrangement of Fig. 4b is adapted to be attached to the end of the socket shown in Fig. 4a;

Fig. 5 shows that end of the the socket ar-. rangement which is on the other side of Fig. 4a., and illustrates the manner in which the holes in the socket are adapted to receive the base arrangement of the electron discharge device tube;

Fig. 6a is an exploded view of one type of prong receptacle used in the novel socket of the invention, adapted for by-passing radio frequency energy to the metallic walls of the socket;

Fig. 61) illustrates another type of prong receiving receptacle for the socket of the inven tion, not adapted to by-pass radio frequency energy to the Walls of the socket;

Fig. 7 is an end view of the push-pull oscillator as seen looking into the left hand end of Fig. 2

Fig. 8 illustrates an exaggerated, enlarged view of the essential elements of the push-pull oscillator showing how the electron discharge devices comiect with the regenerative capacitors which are composed of the transmission line conductors and their associated outer concentric tubes; and

Fig. 9 illustrates schematically the equivalent electrical circuit of the shielded ultra short wave system shown in detail in Figs. 1 to 8, inclusive.

Throughout the figures of the drawings, the same reference numerals are employed to designate the same parts.

Referring to Fig. 1 in more detail, there is shown very generally a completely shielded unneutralized push-pull power amplifier excited by a shielded push-pull oscillator arrangement, for use particularly with ultra short waves. The shielded system of Fig. 1 comprises an outer metallic cylinder l containing in its interior a push-

pull oscillator

2, 2 rotatably mounted at one end on a cylinder support 48, and a power amplifier 4 mounted at the other end. The push-pull oscillator

electron discharge devices

2, 2 with their associated parallel rod transmission line output circuit 5, are shown in dotted lines, as is the parallel rod transmission line circuit 6 for the input of the power amplifier, to which the circuit 5 is variably coupled. The

output circuit for the power amplifier is here shown as comprising a transmission line 'I, also in the form of a pair of parallel rods. Transmission line i is pivotally mounted at one end by means of an insulating support 8 external of the metal cylinder 5, to enable access to the amplifier device 3. Elements M, l! and 2| are slidable connectors for tuning the transmission lines. It should be noted, in this connection, that the output anode electrodes of the amplifier l extend through one end of its envelope, while its input electrodes pass through the other end of its envelope into a socket 28, to be described later. Cylinder I, with its apparatus, is shown mounted on a pair of supporting blocks 9, t, either of an insulating or metallic character, and is maintained at ground or zero radio frequency potential.

In order to more clearly understand the nature of the ultra short wave system of the invention, shown very generally in Fig. 1, reference will now be had to Fig. 9, which shows the equivalent electrical circuit. This figure shows a pushpull oscillator system comprising two

electron discharge devices

2, 2, whose tuned output circuit 5 is variably coupled to the tuned inputcircult 6 of a power amplifier i. The

electron discharge devices

2, 2 of the push-pull oscillator each include a cathode, an anode, and a grid, to the grids of which are connected a pair of choke coils iii serially arranged with respect to each other, and connected to ground through grid resistor ii at their junction point. The cathodes of the

oscillator devices

2, 2 are here shown to be of the indirectly heated type, one leg of each heater element of each tube being connected to ground, while the other leg of the heater element is connected to a terminal of one winding of the low frequency power transformer l2 to Whose other winding is supplied suitable electrical energy from the power line. The anode of each oscillator electron discharge device 2 is connected to one conductor of the two-conductor transmission line 5. The conductorsof this transmission line are parallel, as shown in the drawings, and

in practice constitute rods or hollow tubesj oined at their ends remote from the electron discharge devices by means of a strap E3 to which a suitable sourceof anode supply 3+ is connected. Bridged across the conductors of the line 5 is a slidable connector M for tuning the line 5 .to the operating frequency. A condenser i6 is used to by-pass to ground radio frequency energy induced in the anode supply lead. Around a portion of each conductor of the transmission line 5 located near the anode of the associated oscillator electron discharge device 2, there is provided a concentric metallic cylinder 65 suitably spaced from the transmission line conductor which it surrounds, in order to constitute a capacity therewith. It should be noted that although the anode or" each electron discharge device is directly connected to one conductor of the output transmission line 5, the grid of that device is directly connected to the cylinder i5 associated with the anode of the other electron discharge device of the push-pull oscillator. Since the length of each cylinder it will determine the inherent capacity between the cylinder and that portion of the transmission line conductor which is concentric therewith, it will be apparent that each cylinder together with its associated inner conductor constitutes a regenerative capacitor for one of the oscillator devices, depending upon a judicious selection of the dimensions of the cylinder.

Putting it another way, cylinder 55 is of such diameter and of such length as to provide sulficient regenerative coupling for the grid to which it is directly connected. It will, of course, be apparent that for certain dimensions of the cylincler l5 neutralization of the inter-electrode capacity of the tube may be efiected, but this condition is to be avoided in the present invention, wherein we are mainly concerned with the production of oscillations.

The power amplifier circuit to which the oscillator output circuit 5 is coupled comprises a dual beam tetrode power amplifier tube 4 to whose control grids a two-conductor transmission line 6 is connected. The line 6 consists of a pair of parallel rods or hollow tubes joined together at the ends'remote from the device 4 by a strap l8 connected to ground through a grid resistor I9. A slidable connector ll bridges the conductors of transmission line 6 for tuning the same to the operating frequency. Transmission line 6 comprises the input circuit of the power amplifier 4 and is variably coupled to the transmission line 5 comprising the output circuit of the push-pull oscillator, variation in coupling between

lines

5 and 6 being achieved in this particular case by rotating the conductors of transmission line 5 with respect to transmission line 6 in order to obtain a desired degree of coupling. Maximum coupling between

transmission lines

5 and 6 will be obtained when the planes of both transmission lines are parallel to each other, while minimum coupling will be obtained when the planes of both transmission lines are perpendicular to each other. Intermediate degrees of coupling between transmission lines will be obtained in intermediate positions of the aforementioned positions.

The output circuit of the power amplifier 4 comprises a pair of parallel metallic rods or hollow tubes 1 connected to the anodes of the electron discharge device. The conductors l of the amplifier output circuit are joined at one end by a strap 20 to which the anode supply source 3+ is connected, and are also bridged by a slidable connector 2| fortuning the output circuit.

The beam power electron discharge device 4 comprises an evacuated envelope containing within it two sets of electrodes, each set having a cathode, a grid, a screen grid, an anode, and beam forming plates so spaced that secondary emission from the anode is suppressed without the use of an actual suppressor grid. Such a type of vacuum tube has the advantages of high power output, high power sensitivity, and high elficiency. It should be noted that the beam forming plates of each set of electrodes of the tube are directly connected to its associated cathode, that the screen grids of both sets of electrodes are directly connected to each other and by-passed to the cathodes, both of which are connected together, and, in turn, connected to ground. In efiect, the electron discharge device 4 comprises a pushpull radio frequency beam power amplifier, such as is sold commercially under the trade-name RCA-832. The general structure of each set of electrodes of amplifier 4 is also shown and described in United States Patent No. 2,107,520, granted February 8, 1938, to 0. H. Schade, except for the inclusion of the internal shield within the envelope of the vacuum tube. Although a particular type of beam power amplifier tube has been shown and described, it should be distinctly understood that the invention is not limited to this particular type of amplifier tube since other types of amplifier tubes may also be used.

Figs. 2a to 2 inclusive, combine to show an exploded view of the elements constituting the mechanical structure of Fig. 1. Referring to Fig. 2a, there is shown in some detail a hollow metallic cylinder I mounted on supports 9, 9 and having externally of the cylinder, as shown, an insulating mounting 8 for the amplifier output transmission line 1. Mounting 8 is pivotally supported by means of hinge 22 so as to be able to raise the transmission line "I away from the power amplifier tube 4 to provide access to the amplifier tube and the equipment associated with it. The ends of the conductors constituting the transmission line 1, which contact with the anodes of the amplifier device 4, are provided with phosphor bronze spring clips 23, 23, so as to make good electrical contact with the anode prongs 24 of the amplifier. The slidable connector 2|, which is bridged across the conductors of the transmission line i, is composed of two slotted sleeves connected together by a metallic cross piece Similar slidable connectors l4 and H are also used for the

transmission lines

5 and 5,

respectively.

Fig. 2b illustrates the transmission line 6 constituting the input circuit for the power amplifier 4, both the transmission line B and the pewer amplifier 4 (shown in Fig. 2d) actively cooperating with the novel type of socket shown in Fig. 20. More particularly, the transmission line 8 of Fig. 2?) has both of its conductors mounted on an insulating support 25, the latter being provided with a pair of spaced holes 26 for accommodating a pair of mounting studs 21 of the socket of Fig. 20.

Figs. 2b, 2c, 2d and 2e indicate the exact positioning of the power amplifier input circuit, socket, power amplifier tube, and external metallic shield, respectively, as they would appear immediately after being dis-assembled from the socket. The structure of Fig. 2b, as seen when looking at it from the socket of Fig. 2c, is shown in Fig. 4b.

The novel socket arrangement of the present invention as indicated in Fig. 2c, the end views of which appear in Figs. 4a and 5, comprises a metallic cylinder 28 divided into two sections by a transverse metallic shielding partition 29, one of said sections, namely the left as shown in Fig. 2c, is adapted to be inserted in the right hand end or cylinder l of Fig. 2a, while the other of said sections is adapted to accommodate the amplifier tube 4 and the external shield 39 for the amplifier, the expression "eXternal being used to indicate that the shield 38 fits over the amplifier tube and that its reduced end aligns with an internal shield within the envelope of the amplifier l, said shield not being shown.

Fig. 4a shows an end view of the socket of Fig. 2c, illustrating in detail the prong receiving terminals already shown in perspective in Fig. 20. It should be understood that the power amplifier electron discharge device is located on the other side of the partition 29 and will not be seen in the view of Fig. 4a, even though the prongs of the amplifier electron discharge device will project through holes in the partition 29 for engagement with the prong receptacles. The prong receptacles or receiving terminals of Fig. 4a are illustrated in more detail in Figs. 8a and 61). Fig. 6a illustrates an exploded view of one type of prong receiving terminal for the socket, which terminal is by-passed directly to he shielding partition 29 as a result of its construction. More specifically, this type of terminal comprises a phosphor bronze spring clip 3| Whose end 32 is adapted to grip the vacuum tube prong, a slotted stud 33 for mounting the clip 3|, a metallic plate 34, a mica sheet 35, an insulating bushing 36 arranged to be flush with the shielding partition wall 29, a mica sheet 31 on the other side of the partition 29, and associated with said elements washer 38, a screw 39 and a nut 40. The elements of Fig. 6a are arranged in the position that they appear in before being assembled.

It will be noted that the plate 34 is insulated from the partition 29 by means of

mica sheets

35 and 3?, thus providing capacitive coupling to this partition for lay-passing radio frequency energy. The bushing 36 insures the fact that the metallic stud 33 is not directly grounded to the partition wall. The partition wall 29 is provided with a hole ll sufficiently large to permit the prong of a vacuum tube to pass through the hole without contacting the partition wall. The small hole 42 in the mica sheet 35 and the small hole 43 in the metallic plate 34 are arranged in alignment with the hole 41 of the partition 29 and with the end 32 of the clip 3i to guide the prong of the electron discharge device into the end of the clip 3!. The screw 39 and the immeiately adjacent washer 38 firmly hold the clip 3| in position within the slots of the stud 33.

Fig. 62) illustrates the details of a prong receiving terminal which is not by-passed for radio frequency energy to the partition shield 29. Two sets of terminals such as are shown in Fig. 6b are employed in the socket in connection with the control grids of the power amplifier tube 4 for connecting said grids to the input transmission line B. The prong receiving clip 3i of Fig. 6b is supported by the insulator 25, in turn mounted on supporting stud 2?. The plate 36 of Fig. 6b is also mounted on support 25, immediately beneath clip 3! and physically spaced from shielding partition 29. A hole 4 is provided in partition shield 25 in alignment with a small hole in plate 34 and the end 32 of clip 3% of Fig. 6?) for receiving the prong of the amplifier tube. Due to the size of the hole M, the prong which is adapted to pass therethrough does not contact the shield 2i), and due to the spacing of the plate 3 1 from the partition shield 29, he arrangement is such that there is no appreciable by-pass effect for the radio frequency energy. It will be obvious, of course, that supporting stud 2? is of such size as to keep the insulating support 25 and associated prong receptacle elements spaced away from the shielding partition 29. The end of the socket which is adjacent the base of the amplifier electron discharge device 4, is shown in Fig. 5. This figure is a rear View of Fig. 4a. The two screws for the supporting studs are labeled by reference numerals It should be noted that in some of the holes there is to be observed a portion of the mica sheet 35 located on the opposite side 01" the partition wall 29. It should also be observed that there is one prong receiving hole 4% in the partition wall 2%} which is of different size than the other prong receiving holes. This difierently sized hole 45, in combination with the large diameter pin of the vacuum tube, permits orientation of the vacuum tube as it is placed in the socket, thus preventing improper insertion of the vacuum tube into the socket. The large central hole is provided merely to accommodate the glass tubulation seal-off oi the tube. Of course, where such a seal-off is not present, the central hole in the partition 29 will be dispensed with.

From what has been said before, an inspection of Fig. 4a will show that there are three terminals of the type indicated generally in Fig. 6a and two other prong receiving terminals 41 similar to Fig. 6a, except for the omission of the plate 34 and mica insulation 35. These last two terminals 41 provide a direct grounding to the partition 29 for certain of the electrodes of the amplifier tube. There are also two other terminals, like Fig. 6b, for the socket, which terminals are mounted on the support 25 for the transmission lin 6, as shown in Fig. 4b. These are not shown in Fig. 460, except for the holes 44 in the partition 29.

Fig. 2 shows how the push-pull oscillator with its pair of

vacuum tubes

2, 2 and associated anode transmission line 5, are mounted in a rotatable metallic cylinder support 48, the entire assembly being adapted to be inserted into the open left hand end of hollow cylinder I of Fig. 2a. An outer removable metallic cover 49 is provided for covering the open end of the pushpull oscillator cylindrical ring 48.

Fig. '7 shows an end view of the push-pull oscillator arrangement looking into the cylinder I, with the cover 49 removed. It should be observed that each vacuum tube is mounted on prongs, several of which are placed on a metallic shelf i) and others being placed on insulators 5|, the latter also functioning to support the outer cylinders l5 of the regenerative capacitors. It should be noted that while one conductor of the transmission line 5 goes directly to one electrode of the vacuum tube (the anode) the surrounding cylinder l5 connects with another electrode (the grid) of the adjacent vacuum tube.

Fig. 8 illustrates the essential details of the manner of connection of the transmission line conductors 5 and cylinders [5 to the electrodes of the

oscillator vacuum tubes

2, 2. This figure shows how the lead connections between the tubes and associated regenerative concentric capacitors are minimized.

In the assembling of the elements of Figs. 20. to 21, inclusive, constituting the structure of Fig. l, the transmission line 5 of the push-pull oscillator is located below the transmission line 6 and concentric with the outer cylinder l. Maximum coupling between the two transmission lines is obtained when the planes of the

transmission lines

5 and 6 are parallel to each other. To vary the coupling between the transmission lines, the cylinder support 58 for the push-pull oscillator and transmission line 5 can be rotated within the left hand end of the cylinder I, thus rotating the plane of the transmission line 5. Minimum coupling between

transmission lines

5 and 5 will be obtained when the plane of the transmission line 5 is perpendicular to the plane of the transmission line 5, While intermediate degrees of coupling are obtainable between the above mentioned two positions. The extreme positions which the planes of the

transmission lines

5 and 6 may take are indicated in Fig. 3, which shows a cross section view of Fig. 1 along the lines 3-3. The dotted lines indicate the position of minimum coupling of the transmismission line 5 to the transmission line 6, while the solid lines indicate the position of maximum coupling to the two transmission lines. The arrow heads of Fig. 3 indicate the directions of rotation of the push-pull oscillator unit as a 7 Whole.

Although the cylinder I, socket 28 and ring 48 have been shown as annular, or perfectly round, it will be appreciated that the shape of these elements may depart from a perfect circle and be polygonal in form. Consequently, the term cylinder used in this specification and appended claims is to be deemed of broad scope so as to cover other shapes, such as polygonal forms.

It is to be distinctly understood that the present invention is not limited to the specific arrangements described in the specification and illustrated in the drawings, since various modifications may be made without departing from the spirit and scope of the invention. As an example, where desired, the unit illustrated in Fig. 1 may be arranged to drive or feed another similar unit placed end-to-end, in which case it may be advisable to locate the amplifier output transmission line circuit 1 within a similar metallic container I of the succeeding stage. Nor is the invention limited to an oscillator driving an amplifier; if desired, a unit may be constructed where one amplifier stage excites a succeeding amplifier stage, both stages being located within a single metallic container such as I. It should also be understood that the socket arrangement is independent of its particular application shown and described in the specification, since it may be used wherever there is need for such an arrangement.

What is claimed is:

l. A socket for an electron discharge device comprising an electrically conductive hollow cylinder, an electrically conductive partition wall dividing said cylinder into two hollow integrally connected sections, one of said sections being adapted to accommodate an electron discharge device, terminals mounted on said partition in the other of said sections for engaging the prongs of said electron discharge device, said partition having holes therein for enabling the prongs of said device to pass therethrough to contact said terminals, and dielectric spacers located between certain of said terminals and said partition for producing a capacitance therebetween, whereby radio frequency energy on said terminals can be icy-passed to said partition, and hollow removable shields at both ends of and in telescopic relation to said cylinder for shielding said terminals in one section and said electron discharge device in the other section from external circuits.

2. The combination with a socket for an electron discharge device comprising an electrically conductive hollow cylinder, an electrically conductive partition wall dividing said cylinder into two hollow integrally connected sections, one of said sections being adapted to accommodate an electron discharge device, terminals mounted in the other of said sections for engaging the prongs of said electron discharge device, at least one of said terminals being capacitively coupled to said cylinder for providing a low impedance path to said cylinder for energy of the operating frequency, said partition having holes therein for enabling the prongs of said device to pass therethrough to contact said terminals, of hollow removable metallic shielding means at both ends of said socket engaging the walls of said sections for shielding said terminals in one section and said electron discharge device in said other section from external circuits.

3. A push-pull oscillator comprising a pair 01 electron discharge devices, each having a pair of cold electrodes, a pair of regenerative capacitors each of which is composed 01' an inner conductor and a surrounding outer conductor suitably spaced and dimensioned, the inner conductor of one of said capacitors being connected to one of said electrodes of one device, and the outer conductor thereof to a non-corresponding electrode of the other device, said other regenerative capacitor having its conductors similarly connected to the other electrodes of said devices, one of said conductors of one of said regenerative capacitors and the correspondingly located conductor of the other regenerative capacitor constituting part of a tuned transmission line circuit for said oscillator.

4. A push-pull oscillator comprising two electron discharge devices, each having a grid and an anode, two regenerative capacitors each of which is composed of a pair of concentric conductors suitably spaced and dimensioned, the inner conductor of one capacitor being connected to the anode of one device while the outer conductor of said same capacitor is connected to the grid of the other device, the inner conductor of said other capacitor being connected to the anode of said last device while the outer conductor of said last capacitor is connected to the grid of said one device, said inner conductors of said two regenerative capacitors forming part of a tuned transmission line circuit for said oscillator.

5. A push-pull oscillator comprising two electron discharge devices, each having a grid and an anode, two regenerative capacitors each of which is composed of a pair of concentric conductors suitably spaced and dimensioned, the inner conductor of one capacitor being connected to the anode of one device while the outer conductor of said same capacitor is connected to the grid of the other device, the inner conductor of said other capacitor being connected to the anode of said last device while the outer conductor of said last capacitor is connected to the grid of said one device, said inner conductors of said two regenerative capacitors forming part of a transmission line constituting the output circuit of said two electron discharge devices.

6. A push-pull oscillator comprising a pair of electron discharge devices, each having a pair of cold electrodes, a pair of regenerative capacitors each of which is composed of an inner conductor and a surrounding outer conductor suitably spaced and dimensioned, the inner conductor of one of said capacitors being connected to one of said electrodes of one device, and the outer conductor thereof to a non-corresponding electrode of the other device, said other regenerative capacitor having its conductors similarly connected to the other electrodes of said devices, one of said conductors of one of said regenerative capacitors and the correspondingly located conductor of the other regenerative capacitor constituting part of the output circuit for said oscillator.

7. A shielded multi'stage ultra short wave system comprising a metallic cylinder, an electron discharge device stage located within and supported at one end of said cylinder, a succeeding electron discharge device stage located within and supported at the other end of said cylinder, a tuned output circuit for said first stage and a tuned input circuit for said succeeding stage, both of said tuned circuits being located one above the W tive to that of the other for varying the coupling therebetween.

8. A shielded multi-stage ultra short wave system comprising a metallic cylinder, an electron discharge device stage located within and supported at one end of said cylinder, a succeeding electron discharge device stage located within and supported at the other end of said cylinder, a tuned output circuit in the form of two parallel conductors for said first stage, and a tuned input circuit also in the form of two parallel conductors for said succeeding stage, said tuned circuits being located one above the other within said cylinder and between said devices, said tuned circuits being coupled to each other, and means for rotating the plane of one tuned circuit with respect to the plane of the other tuned circuit, for varying the coupling between the tuned circuits.

9. A shielded multi-stage ultra short wave systern comprising a metallic cylinder, an electron discharge device stage located within and supported at one end of said cylinder, a succeeding electron discharge device stage located within and supported at the other end of said cylinder, a tuned output circuit in the form of two parallel conductors for said first stage, and a tuned input circuit also in the form of two parallel conductors for said succeeding stage, said tuned circuits being located one above the other within said cylinder and between said devices, said tuned circuits being coupled to each other, one of said tuned circuits being substantially concentric with said cylinder, and means for rotating the plane of one tuned circuit together with its associated stage within said cylinder for varying the coupling between tuned circuits.

10. A shielded multi-stage ultra short wave system as defined in claim 9, characterized in this that said first stage is a push-pull oscillator, and said second stage is a power amplifier.

11. A shielded multi-stage ultra short wave system comprising a metallic cylinder, a pushpull electron discharge device oscillator stage located within and supported at one end of said cylinder, a succeeding electron discharge device power amplifier stage located within and supported at the other end of said cylinder, at tuned output circuit in the form of two parallel conduc tors for said first stage, and a tuned input circuit also in the form of two parallel conductors for said succeeding stage, said tuned circuits being located one above the other Within said cylinder and between said devices, said tuned circuits being coupled to each other, one of said tuned circuits being substantially concentric with said cylinder, and means for rotating the plane of one tuned circuit together with its associated stage within said cylinder for varying the coupling between tuned circuits, said power amplifier having an output circuit externally of said cylinder in the form of a pair of tunable parallel conductors.

12. The combination with a socket for an electron discharge device comprising an electrically conductive hollow cylinder, an electrically conductive partition wall dividing said cylinder into two hollow integrally connected sections, one of said sections being adapted to accommodate an electron discharge device, terminals mounted in the other of said sections for engaging the prongs of said electron discharge device, at least one of said terminals being capacitively coupled to said cylinder for providing a low impedance path to said cylinder for energy of the operating frequency, said partition having holes therein for enabling the prongs of said device to pass therethrough to contact said terminals, of hollow removable metallic shielding means at both ends of said socket engaging the walls of said sections for shielding said terminals in one section and said electron discharge device in said other section from external circuits, said removable shielding means being in telescopic relation to said cylinder.

13. A shielded multi-stage ultra short wave system comprising a metallic cylinder, an electron discharge device stage located within and supported at one end of said cylinder, a succeeding electron discharge device stage located within and supported at the other end of said cylinder, a tuned output circuit for said first stage and a tuned input circuit for said succeeding stage, both of said tuned circuits being located within said cylinder and coupled to each other, one of said stages being mounted in a socket which is in telescopic relation to said metallic cylinder,- said socket comprising a hollow metallic tube having a metallic partition wall dividing said tube into two hollow integrally connected sections, one of said sections being adapted to accommodate the envelope of said one stage, terminals mounted on said partition in the other of said sections for engaging the prongs of said stage, said partition having holes therein for enabling the prongs of said stage to pass therethrough to contact said terminals, at least one of said terminals being capacitively coupled to said partition for providing a path of low impedance to said tube for high frequency energy.

WILLIAM H. HAPPE, JR.

ARTHUR K. WING.