Патент USA US2408194код для вставки
I Sept. 24, 1946. H_ 5 BEST]; PHASE SHIFT'ER ‘ 2,408,193 Filed Dec. 6, 1943 arrow/Er Patented Sept. 24, 1946 2,408,193 UNITED STATES PATENT OFFICE 2,408,193 PHASE SHIFTER Harold Edward Beste, East Rutherford, N. J ., as signor to Allen B. Du Mont Laboratories, Inc., Passaic, N. J., a corporation of Delaware 1 Application December 6, 1943, Serial No. 513,136 ‘4 Claims. (01. 172—-246) This invention relates to a phase shifter which comprises a transformer of which the primary is in the cathode circuit of a vacuum tube. The invention may be understood from the 2 are of the same frequency as those in coil 6 but of opposite polarity thereto or 180° di?erent from coil 6 in phase. The phase of the voltages applied to the con description in connection with the accompanying denser l3 and therefore to the control grid of drawing, in which reference character I indicates tube l5 depends upon the relative impedances of a connection from a source of alternating cur the condenser I 2 and the portion of resistance II rent which may, for example, be of a frequency that is in series across the secondary 8, 9 of the of 100 c. p. s. The terminal 1 is coupled by transformer ‘I. When the contact II’ is at the condenser 2 to the grid of triode 3 which has 10 lower end of resistance II, the voltage at the grid leak '4. The cathode 5 of tube 3 is con grid of tube I5 is approximately90° ahead of nected to one end of the primary 6 of transformer that across the secondary 8, 9, and the more of ‘l, the other end of, which is grounded. the resistance II that is placed in the circuit Two like coils 8 and 9 connected in series and by moving contact ll’ closer to the upper end grounded ‘at the center it constitute the sec 15 of resistance II the nearer the voltage at the ondary of the transformer ‘l. The lower end grid of tube I5 is in phase with the voltage across of the secondary i9 is connected to one end of a ' the secondary 8, 9. variable resistance H, and the upper end of the The current through the coil 6 is not depend coil 8 is coupled by condenser IE to the upper ent upon the phase or amount of current through end of resistance II. A sliding contact II’ is 20 the coils-8 and 9, as this current depends pri provided to vary the portion of the resistance H marily upon the voltages at the grid and plate 7 that is in the circuit. of tube 3. > A condenser 13 couples the phase shifter Due to the comparative low impedance and through resistance Id to the control grid of tri high current in coil 6, any change in phase due ode l5, this grid being provided With a grid leak 25 to adjustment of contact l I’ results in very little, IE’ to ground. The cathode of tube I5 is con if any, change in voltage output of this phase nected to the cathode of tube l6, and both are shifter. connected to ground through resistance IT. A What is claimed is: lead 18 extends from a source of positive potential 1. In an electronic device for shifting the phase 30 through load resistances l9 and 20 to the plates of voltage, a vacuum tube to the control grid of of the tubes l5 and I5. And this lead I 8 is also which said voltage is to be applied, and a trans connected through resistance 2| to the screen former having its primary ‘connected between grids of the tubes l5 and H5 in the usual way. The tubes l5 and I6 and connections consti tute or provide a balanced phase-inverter de?ec tion ampli?er, from which signals of opposite polarity can be taken and coupled by condensers the cathode of said tube and ground, the ends I of the secondary of said transformer being con 35 nected to a resistance and capacitance in series. 2. The device of claim 1, in which said re sistance is variable. 3. The device of claim 1, in which an output 22, 23 and leads 24, 25 to a pair of de?ection plates of an oscillograph cathode-ray tube not lead is connected between said resistance and shown. 40 capacitance. The oscillations fed in at I and applied by 4. The device of claim 1, in which said sec tube 3 pass through the primary 6 of transformer ondary is grounded. 1, setting up voltages in the coils 8 and ,9 which ' HAROLD EDWARD BES'I'E.