US1893605A - Transmitter arrangement - Google Patents

Description

Jan. 10,1933. G, VON ARCO 1,893,605

TRANSMITTER ARRANGEMENT Filed Aug. 15.. 1927 INVENTOR GEORG VON ARCO A RNEY Patented Jan. 10, 1933 UNITED STATES PATENT OFFICE GEORG VON ARGO, OF BERLIN, GERMANY, ASSIGNOR TO TELEFUNKEN GESELLSCHAFT' FOR DRAHTLOSE TELEGRAPHIE M. 13. IL, OF BERLIN, GERMANY, A CORPORATION OF GERMANY TRANSMITTER ARRANGEMENT Application filed August 13, 1927, Serial No. 212,681,'and in. Germany October 30, 1926'.

For short-wave transmission work, transmitter valves or tubes are mostly used which comprise a plurality of series-connected (cascade connected) separately-excited tubes, the oscillations being produced by a thermionic tube subject to the control of an oscillating crystal. As as general rule, the useful or working frequency is a multiple of the frequency generated by the crystal-controlled oscillator or transmitter valve. In one of the tubes comprised in the cascade arrangement, frequency multiplication is effected.

Now, in order to enhance the performance and power of such frequency multiplication arrangement, it would be possible both to choose larger units or to connect a number of the tubes in parallel. In either case and scheme, an unavoidable characteristic of the active internal tube capacity is produced, whereby the proportions of the outer oscillation circuit become difficult, if not wholly impossible under certain circumstances so far as the extremely high frequency to be pro duced is concerned. Another way of raising the power of the transmitter apparatus consists in building the different tube sets or assemblies separately, and to couple each one thereof, if desired, by way of an oscillation circuit, to the common antenna, the grids of the different tubes being controlled jointly. Now this in turn involves the difliculty that the difierent tubes sufier alterations in the course of operations. In other words, the tube constants of the different tubes are subject to different influences with the result that, in order to insure satisfactory operation of the individual tubes, the latter mustbe supplied with grid potentials of different value, and this would necessitate the provision of complicated correcting means.

Now, the present invention discloses ways and means with the end in view to raise the total power of the transmitter plant without the arrangement of a separately controlled cascade-connected tube transmitter by that, according to this invention, a self-excited tube transmitter is joined with the antenna adapted to generate additionally oscillations of the working frequency. In order that the selfexcited transmitter tube may produce oscillations of adequate constancy of the desired frequency, connection is established with the antenna in such a way that its grid circuit is in sufliciently close coupling relationship with the separately-excited crystal-controlled transmitter so that the self-excited transmitter will be made to work in what is known as the entraining range or the range of forced oscillations, in which, as is well known the frequency of the oscillations is governed and maintained by. the frequency of the oscillations supplied from the outside.

One embodiment of the invention is shown by way of example in the accompanying drawing. A is the sending antenna which, in well-known manner, is excited by the tube cascade comprising the tubes S1, S2 and S3, the first tube S1 being controlled by a crystal K. Now, according to the disclosure of the present invention, a self-excited tube transmitter R is further connected with the aerial. Preferably variable couplings are provided between the antenna and the grid circuit coil of oscillator R, between the working circuit or plate coil and the antenna, and, between the grid and the plate circuit of tube R as illustrated. These couplings are so adjusted that the self-excited tube transmitter, as previously pointed out, operates within the range of forced vibrations. It will be understood that the drawing illustrates only one embodiment of the invention, it being obvious that a number of other self-excited tube transmitters may be added in a similar manner.

It is to be understood that the invention is not limited to the embodiments and features specifically shown and described herein, but that such embodiments and features are sub ject to changes and modifications without any departure from the spirit of the invention.

What I claim is:

1. A transmitter comprising an antenna, a

crystal controlled oscillatory circuit coupled to said antenna, and, a normally inoperative self-excited tube oscillator arrangement also coupled to said antenna, the couplings being adjusted so that upon operation of said crystal controlled oscillatory circuit, said self-excited tube oscillator arrangement is brought H into operation at a frequency controlled by said crystal controlled oscillatory circuit.

2. In combination, an antenna, a crystal controlled oscillatory circuit operating at a 5 desired working frequency coupled to said antenna, and, a self-excited vacuum tube oscillator also coupled to said antenna, said self-excited oscillator being adjusted to operatewithin a predetermined range of opera- 1 tion and being controlled in frequency by said crystal controlled oscillatory circuit by virtue of its coupling to said antenna.

3. In a high frequency system, a high frequency output circuit, a crystal controlled oscillation generating circuit coupled to said output circuit, and, a high powered regenerative oscillator, said high powered oscillator being adjusted and coupled to said common high requency output circuit whereby it is changed, upon operation of said crystal controlled circuit, from a normally inoperative condition to an operative oscillating condition, oscillating at a frequency controlled by the frequency of operation of said crystal controlled oscillation circuit.

GEORG VON ARGO.

Patent No. 1,893,605. January 10,1933. Certificate of Correction GEORG VON ARGO It is hereby certified that error appears in the printed specification of the abovenumbered patent requiring correction as follows: Page 1, line 7, for as second occurrence read a; and after line 84, insert the following paragraph I t is evident in the invention as shown that in key work as 'well as in telephony both the transmitters, that is, the separately ecceited transmitter S and the entrained transmitter R must be keyed 0r modulated as the ease may be; page 2, line 19, claim 3, for requency read frequency; and that th e said Letters Patent should be read With these corrections therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 4th day of April, A. D. 1933.

. M. J. MOORE,

Acting O0mmissi0ner of Patents.

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