US1744711A - Radio transmitting system - Google Patents

Abstract

244,121. Telefunken Ges. f³r Drahtlose Telegraphie. Dec. 6, 1924, [Convention date]. Thermionic generators; directive signalling.- A short-wave valve transmitter comprises a number of power amplifiers connected in parallel to a common plate or aerial circuit, and with their grid circuits excited by the several phases of an n-phase source. As shown in the Figure, an oscillator H is coupled to an artificial line K, and the grid circuits E, F, G of the three valves A, B, C are coupled to the line at points giving 120‹ phase displacement. The common aerial or plate circuit D is tuned to a frequency three times that of the source, and the valve grids are biassed by a battery so as to pass current during only one-quarter period of the higher frequency. For directive working, a number of spaced aerials are employed, a set of valves such as A, B, C is associated with each aerial, and the grids of these valves are excited in different phases by coupling the grid circuits of each set to an artificial line K, these lines being connected in series and energized by the source H of lower frequency. The artificial lines may be omitted if standing waves of suitable length are created in the cable by the current supplied by the source H.

Description

Jan. 21, 1930.

ca. von ARCO RADIO TRANSMITTING SYSTEM Filed Nov. 23, 1925 INVENTI'OR Geoae Von HRCO ORNEY fimefib STATES PATENT OFFEC ezona von A300, 02 BERLIN, GEBMANY,

ASSIGNOR T GESELLSCHAFT FR. DRAIH'ILOSE TELEGRAPHIE' III. B. H. HALLESC'HES, OF BERLIN, GERMANY, A GORIPORATION O]? GEW-- RADIO TBANSMI'ITING SYSTEM Appli cation flled November 23, 1925, Seria1 N0. 70,729, and in Geimany Decem'ber 6, 1924.

My invention relates to radio signaling systems and particularly to phase splitting und frequency multiplying means in connection therewith.

An ob'ect of my4 invention is to rovide a radio requency geznerator adapte to the generation ofrelatively very high radio frequencies.

- Another object of my invention is to provide in combination a radio frequency enerator and an amplifier adaptecl to mult1ply the frequency thereof.

Another object of my invention is t0 provide a rad io frequency generating system adapted to generate large powers at very high 1 frequencies.

Another object 0f my invention is to provide means for counteracting the efi'ect cf tube capacitance in the generation of radio frequencies above 1500 kilocycles.

In the normally separately-excited vacuum tube tra'nsmitters, havin a master oscillator, the workin or power tu es play the art of a powerful igh frequency amplifier, and they excite by direct current impulses in theanode 01 platze circuit an oscillation circuit tuned to the exciting frequenc the radiation energy being taken I"iom sai oscillation circuit.

1s system in reasonably satisfactory at.

relativelfy 10W radio frequencies and longer wave lengths but is not so satisfacto1y at shorter wave lengths and higher frequencies, since at these frequencies the intevelectrode capacitane of the tubes becomes a large facto1 in the tuning of the circuits and may become so large as to prevent the production at all of oscillations at the frequency desired. The subject-matter of the present invention consists in -exciting seve'ral high frequenc amplifier tubes of large power in parallel wit Phase displaced exc1ting currents from the master oscillator und in causing them to act u on a. common anode circuit said anbde or p ate circuit, being tuned in tl1e case of parallel tubes to the n-fold fr uency, instead of 110 the excitin frequency. would be a t ree-phase excitation. In this case the co'mmon platze circuit would be tuned to a frequency three times the frequency of theexciting currents from the master 0scil- 'ing a triode vacuum tube 2 e simplest case later. The three tubes used deliver in each excitation period three successive D. C. impulses to the common oscillat'ory circuit. In this scheme it is necessary to tive grid voltage in the amp ifier tubes, anal t-o s'o adjust it to such a value that the eriod during which the plate current is owing will not be longer than the duration of a quarter-period of the triple frequency compared with the exciting oscillation.

Other objects and structural details 015 my invention will be apparent from the follow- -1ng description when read in connection with the accompanying drawing, wherein:

The single figure is a diagrammatic representation of c'ircuits and apparatus embodyin my invention.

the figure a master oscillator 1 comprishaving filament heat ing means 3, a plate current generator 4 and a local re sonant circuit consisting of an inductance 5 and a capacitance 6. A phase splitter 7 is provided and supplied from coil 8 in inductive relation to the coil 5 and delivering phase displaced energy to the primary coils of the high frequency transformers 9, 11, and 12. A multi lying amplifier 14 is rovided consisting 0 trio e, Power ampli% ving tubes 15, 16, and 17 the filaments of which am energized by a current source 18, the plate circuits of which are energized by current source 19. The respective grids are energized by the secondaries of the respective transformers 9, 11, and 12 and the gr1ds are suitably biased electrically by a gmd potential source 21. A reas0nant circu1t comprising an inductance 22 and a capacitance 23 is provided and connected in the lead between the parallel connection to the plates of the respective triodes 14, 15 and 16 and the generator 19. A reson&nt radiating circuit' 24 is provided und suitably coupled to the local resonant circuit.

The resonant circuit comprising the inductance 5 and the capacitance 6 may then be tuned to a. frequency that to which the resonant circuit comprising the inductan'ce 22 and capacitance 23 is tuned. This ratio is determined by the numberof phases produced by the phase splitter 7.

rovide a nega- 'by any convenient means In the Operation :E my device the local master oscillator 1"may be set to geherate at any convenierit frequenc'j and may be keyed (not shown) Its output is then supplied to the Phase splitter 7 Which in the instance given produces three separate currents having the same frequency as the input but displaced in phase relationrent causes pulses of current to ship by 120 electrical degrees. The successive positive half cycles cf these three phase outputs are then supplied to the grids of the triodes 15, 16, and 17. The grid bias source 21 is adjustiad to supply such a negative potential to the grids that the peak only of each positive half cy ':le brings them to such a positive potential as to perm1t current to flow.

. This sequence of the positive pulses of Curflow through the power tubes in succession. This succession causes pulses to flow in the generator lead at a frequency the output o:t the master oscillator 1. This of esp&zcially h igh frequencies,

however, that to whieh triple frequency is,

' in the plate lead -is tuned internal capacity o'f high-power amplif ier in the usual arrangement.

to the hase splitter,

tubes between the anode working current and the exciter tube is diminished 011 the ground thsit working frequericy. ai1d' exciting frequency are then difierent, while they are alike An0ther advantage consists in that the exmting circuit may be designed for a relatively lower frequency, g with the consequence that its wave can be kept constant more readily, and that the coustancy of the exciting period insures coustancy of the raised frequency of the working circuit.. a

It is not necessary i the practice of my invention that the triple frequency arrange-- ment described in illustration be adhe1 ed to, but any desired ratio may be substituted, therefore'.

While I have shown but one embodiment of' my invention in the foregoing descriptiqn it is Capable of various modifications therefrom without departing :Erom .the spirit thereof, and it is desired therefore that only such limitations shall be imposed thereon es are required by the prior art o1 indicated by the appended claims.

I claim as my i1'1vention: 1. In combination, a radio frequency master oscillmtor, a pha.se splitten coupled to seid oscillator, a. plurality of amplifiers coupled and biased for-sharpcut efi and a. resonant circuit tuned to a irethree time the frequency of;

a. common prlate cireuit 00 .plifier systems quency which is a. to which seid first mentioned resonant 211- cuit is tuned, coupled to' sa.id amplifiers.

2. In combination, a thermionic radio ire quency maSter oscillator having a resonant circuit, a hase splitter coupled to seid resonant circuit, a plurality of amplifiers coupled to -=re'spe ctwe output circuits of seid phase splitter, a second resonant circuit coupled to the output circuits cf said amplifiers and mea.ns to tune seid second resonant 011"- cuit to a frequency which is a multiple of the frequency to which seid first mentioned resonant circuit is tuned, the ratio .between the frequencies 0f seid resonant circuits being equal to the number of phases produeed by seid phase splitten 3. The method of generating high radio frequecies which comprises enerating a subfrequency, splitting seid su -frequency into a. plurality of phases, separately amplifying an'd shortening succes sive positive pulses of' each of thephases, andt':o;ubining all of said amplified and shorteneld pulses in's common resonant circuittun6d to the desired frequency multiple.

4. In combination, a.wacuufii mitter adapted to work with 1 extra short waves having thermionic means for generating' a fundamental f'1e uency, me'ans for multiplying seid fundam plurality of high Power amplifier' tnode t1'1bes excited in phase disp= ected thereto and tuned to a equenc equal to the excitin frequenc{y multiplied %y 'the 5. n combination, a thermionie enerator, a hase splitter supplied therebgt 01 tr'ansforming single phase to three p as amplifiers assoc1ated with said hase splitter, rid bias means for said amplifiers of such magnitude that cu'rrent flows in the amplifier tubes during a. period less than one twelfth of the peripd-of the master oscillator, and a reso1iant circuit tuned to a three-fold multiple ofthe generator frequency coupled to the amplifier tubes.

6. In combination a. thermionic radio frequency master ostsillator, a. phase splitter associated therewit a plurahty o f triode amcoupled to the output circuits splitter, grid bias means for oi seid phase gnitude that curseid amplifiers of such m a rent flows a small portion of the period cfthe master oscillator, und a circu it tuned to a multip of the master oscillator frequency coup tothe amplifiers. u

7. In combination, v. thermionic madig frequenc master oscillator, an output c1rcu1t there er, a hase splitter, an inputcircuit th'erefor c oimected t0 the output circuit of seid master oscillator, amplifiers connected to the output ci rcu1ts of -sa.id pbase splitter,

and a single output tube transtal irequency, a.

1'1umber of p ases.

e energy,

in the amplifier tubes during only le ed multiple of the frequen cy aced fashion und a Plurality of triode circuit tuned to a mu circuit for said amplifiers tuned to a desired multiple of the master oscilla tor frequency.

8. In combinatioh, a thermionic radio frequency masber oscillator, a phase splitter having an input and a. plurality of output circuits, means for connecting said .input circuit 150 said oscillator, a plurality of triode tubes having input and output elements, means for connecting each 0:E said input elements to' a respective one of the output circuits of said phase s fitter, a.nd amoutput tipleof the master oscillator freq uency coupled to the output elements of sa1d triodes in parallel relation.

9. In combination, a thermionic radio frev quency master oscillator, a hase splitter connected thereto supplied therefrom, a. plurality of amplifiers each connected to an out put circuit of said Phase splitter, an output circuit for said amp ifiers tuned to a multiple of the master oscillator frequency connecb ing said triodes in parallel relation, und an oscillation radiator coupled to said output circuit.

GEORG von ARCO.

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