US1982916A - Transmitter - Google Patents

Description

Dec. 4, 1934. w KUMMERER 1,982,916

TRANSMITTER Filed Nov. 8, 1930 INVENTOR WILHELM KUMMERER ATTORNEY Patented Dec. 4, 1934 UNITED, STATES TRANSMITTER.

Wilhelm Kummerer, Berlin, Germany, assignor to Telefunken Gesellschaft fiir Drahtlose Telegraphic in. b. H., Berlin, Germany, a corporation of Germany Application November 8, 1930, Serial No. 494,290v

In Germany November 15, 1929 Claims. (01. 250-36) This invention relates to an arrangement for eliminating reaction of the master valve upon a pilot valve in separately excited valve-transmitter equipment. 5 'In German Patent No. 459,005 an arrangement has been disclosed intended to obviate the reaction often produced by the master transmitter valve upon the pilot tube. For this purpose, a resonant short-circuit link or unit is provided in the output circuit of the frequency-multiplication tube tuned to a harmonic of the fundamental wave, said unit being tuned to the fundamental wave, i. e., the wave of the pilot valve. In this way, the reaction produced upon the pilot valve inv the presence of antenna sway will be minimized. I

Now, according to the present invention the operation of the scheme is improved by that a tuned short-circuit path is provided not only in 20 the output circuit of the mastervalve, but alsoin the grid circuit thereof, it being understood that the short-circuit unit in the grid circuit must be tuned to the higher harmonic.

One embodiment of the invention is illustrated in the drawing.

0 indicates an oscillation generator having a control electrode 1 connected through an inductance 3 to the cathode 5. The anode 9 is connected in a high frequency output circuit including blocking condenser C, a unit W having parallel branches 10, 15 and 16, and the cathode 5. Direct current potential is applied to the anode 9 of tube 0 through a choking inductance '7. The inductance 10 is coupled to the inductance 3 in the grid cathode circuit of 0 to produce sustained oscillations at a frequency determined by the elements in the output and input circuits of O.

The unit 10, 6' is also in the input circuit of 40 tube 2, as shown, and impresses potential variations at the frequency generated by O on the input electrodes 11, 13 of tube 2. The unit W has a parallel circuit which is tuned to the fundamental frequency, while the capacity 15 and inductance 16 are series resonant at a harmonic so that such harmonic is not impressed on the input electrodes of tube 2. Anode potential for the tube 2 is supplied through choking inductance 12, as shown. 1 A 50 In the output circuit of the frequency-doubler tube 2 the oscillation circuit 4 consists of a resonant short-circuiting unit 6 in conjunction with a condenser 8. The grid oscillation circuit contains the combination of a resonant (tuned) short-circuiting unit 6' and an inductance 10.

The potentials at the harmonic frequency produced in the frequency doubler tube 2 are set up across the parallel resonant circuit 4 and are applied therefrom to the amplifienfrom which they may be impressed on to the power amplifier and 0;; from thence to the radiating systemn. The branch 6 of the circuit 4 tuned to the harmonic frequency is series resonant, as pointed out in detail hereinbefore, to the fundamental frequency so that potentials at said frequency are short-- 5 5 circuited and are not applied to the amplifier.

In order to prevent potentials at the harmonic frequency-which appear at the terminals of the parallel resonant circuit l connected with the anode of the frequency doubler 2, from modulat- 7 ing or affecting-the fundamental frequency, impressed from the oscillation generator 0 by way of the :circuit W including capacity 15, inductance l0 and inductance 16, which areparallel resonant to the fundamental frequency, due to coupling between said input and output circuits or coupling by way of the impedance of the tube 2, means is provided, as described hereinbefore, in the input circuit of 2V to short circuitthe potentials at the harmonic frequency. This means is, as pointed out in detail I hereinbefore, the series resonant circuit 15, 16. This circuit, being series resonant to the harmonic frequency in the output circuit of 2, acts as a short circuit thereto and therefore no potential difference appears between the control grid 11 and cathode 13 of the frequency doubler representative of the harmonic potentials.

I claim:

1. A frequency multiplier comprising an elec- 0;; tron discharge device having an input circuit tuned to a fundamental frequency and an output circuit tuned to a frequency harmonically related to the fundamental, said input circuit having parallel branches, one of which includes a reactor and the other of which includes inductive and capacitive elements in series circuit tuned to resonance at the harmonic frequency and said output circuit comprising two parallel branches, one of which includes a reactor and the other of which includes a series circuit tuned to series resonance at the fundamental frequency.

2. A frequency developing system comprising an electron discharge device having an input circuit tuned to a fundamental frequency and an output circuit tuned to a frequency harmonically related to the fundamental, said input circuit comprising two parallel branches, one of which includes a reactor and the other of which includes inductive and capacitive elements in a series cir- 110,

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cuit tuned to resonance at impedance to energy of the harmonic frequency and said output circuit comprising two parallel branches, one of which includes a capacitor and the other of which includes a series circuit tuned to resonance at the fundamental frequency thereby offering practically zero impedance to energy of the fundamental frequency.

3. A frequency multiplier comprising, an electron discharge device having anode, cathode and control grid electrodes, an input circuit connected act as a short circuit for said fundamental frequency, and means for preventing oscillations at the harmonic frequency appearing across the output electrodes of said frequency multiplier from being applied tothe input electrodes of said frequency multiplier comprising reactances in one branch of said input circuit to tune said branch to series resonance at the harmonic frequency.

4. A frequency multiplier comprising, an electron discharge device having anode, cathode and control grid electrodes, an input circuit connected between said cathode and grid electrodes, said circuit including parallel branches tuned to the fundamental frequency which is to be applied to said input electrodes, an output circuit connected between the output electrodes of said tube, said quency from being set up across said output circuit comprising, capacitive and inductive react- *multiplier comprising capacitive and inductive reactances in one branch of said input circuit to tune said branch to series resonance at the harmonic frequency;

5. A signalling device comprising, a source of highfrequency oscillations and a load circuit, and means for increasing the frequency of oscillations fromsaid source and applying the increased frequency oscillations to said load circuit comprising, a thermionic tube having its control grid and cathode connected with said source and its anode electrodes connected with said load circuit, a circuit comprising an inductance in parallel with a series capacity and inductance connected between the control grid and cathode of said tube, said circuit being tuned by said inductances and said capacity to parallel resonance at the frequency of said source, a circuit comprising a capacity and a capacity and inductance" in parallel with said capacity connected between the anode and cathode'electrodes of said thermionic tube, said last named circuit being tuned by said capacities and said inductance therein to parallel resonance at a frequency which is a harmonic of the frequency of said source, the capacity and inductance in one branch of said last named parallel resonant circuit being series resonant at the fundamental frequency to provide a short circuit path for the fundamental frequency between said output electrodes, the capacitive and inductive branch in said first named parallel resonant circuit connected between said input electrodes being series resonant to the harmonic frequency to provide a short circuit path between said control grid and said cathode for said harmonic frequency.

WILHELM KUMMERER.

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