Патент USA US2411517код для вставки
2,411,517 Patented Nov. 26, 1946 ‘ UNITED! STATE 5 PAT ‘ I I _ I 2,411,517 _ I OFFICE; H‘ r I ~ ' ' I ' COUPLING AMPLIFIER’ ' ' HenriG; Busignies, Forest Hills,v N; Y., assignor'to' Federall Telephone‘ and Radio Corporation, Newark, N. J'., a» corporationof Delaware; Application January 16, 1943, Serial,No..4'Z2,589.> ' - 3 Claims. 2 1 This invention relates to improvements in coupling ampli?ers, and more particularly to such ampli?ers to be used between anginput circuit ampli?er is assured. For example, if at any gram of a preferred form of coupling ampli?er proper adjustment of resistors 28 and 3!] will be chosen instant the polarity of the input lead I4 is positive and the polarity of the input lead I6 is negative, the coupling will act as an ampli?er. A and a balanced output circuit, as between a direc negative potential will exist on the output lead I8 tive antenna and its transmission line. due to phase reversal through the tube III while An object of this invention is to provide a novel a positive potential will appear on the output lead coupling ampli?er between a balanced or a par 20 due to phase reversal through the tube I2. tially unbalanced input circuit and a balanced The potential on the output lead I8 derived from output circuit. More speci?cally, the invention is directed to a 10 the cathode of tube I2 through condenser 44 will likewise be negative, while the potential on the novel coupling circuit which ampli?es a bal lead 20 derived‘ from the cathode on the tube I 0 anced input, but inherently prevents the ampli through condenser 42 will be positive. Thus, ?cation and through passage of parallel input when a balanced load is placed upon the leads currents or voltages to the output circuit. In another sense, the invention provides a 15 I4 and It, a balanced output on the leads I8 and , 20 results. neutralized push-pull ampli?er which blocks out However, if the potential on both leads I4 and. unbalanced input currents but ampli?es balanced I6, is for example, positive, the ampli?er will act input currents. to block the passage of current, rather than These and other objects and advantages of the present invention will appear from the fol 20 amplify it. This is} due to‘ the fact that while, in such a case, the potential on the lead I8 derived lowing description of a preferred embodiment from the anode of the tube III will be negative, thereof, taken in connection with the following the derived voltage values as determined by‘the drawing in which the single ?gure is a circuit dia according to the present invention. , 25 ' In the preferred form of invention illustrated, I use two vacuum tubes I0 and I2 which may be of such Value that this potential will be neu tralized by the positive potential derived from the cathode of the tube I2. Likewise, by properly proportioning resistors 26 and 32, the negative triodes, as illustrated, generally connected in potential on the lead 29 derived from the anode push-pull relationship. Input lead I4 will be con nected to the grid of triode III, while input lead 30 of the tube I2 will be neutralized by-the potential derived from the cathode of the tube III. The I6 will be connected to the grid of triode I2. The amount of resulting neutralization will, of course, output leads I8 and 20 are respectively connected depend upon the amount of unbalance present to the anodes of the tubes In and I2 through in the input circuit. suitable condensers 22 and 24. In the cathode While the invention has beenparticularly de ' circuit of each tube is placed a resistor, such as 35 scribed in connection with an ampli?er using the resistors 26 and 28, the common mid-point _ between these resistors being grounded.’ The triodes, it can be adapted for use with other _ anodes of the two tubes are seriallypconnected with one another through resistors 30 and 32, multi-electrode tubes. The described ampli?er is particularly well adapted for, use as coupling the mid-point connection of which is grounded 40 units between direction ?nding antennae and transmission lines, in directive antenna'coupling for high frequency currents through the con denser 34. A high voltage source indicated at 35 will also be connected to the mid-point between resistors 30 and 32. Grid-leak resistors 38 and 40 are respectively connected between the individual 45 systems and generally in all balanced types of transmission circuits in which the transmission of parallel voltages or currents or straight recep grids and ground. In addition to the circuit connections‘just out lined, it will be also noted that each cathode of order to comply with the statutes, I have illus trated and described a single speci?c embodiment of my invention, it is contemplated that various the individual tubes is respectively connected changes may be made in the circuit as will appear to the outputlead of the opposite'tube. , tion is to be avoided. Furthermore, while, in 7 For 50. obvious to those skilled in this art and it is there fore to be clearly understood that this descrip example, they cathode ‘of tube I0 is connected tion is made by way of example and not, as a limi- through condenser 42 to the output lead 20, while ‘ tation on the scope of my invention as set forth . the cathode of tube I2 is connected through con in the objects and the accompanying claims. denser 44 to the output lead] 8. .By means of this cross-connection, a balanced output from the 56 I claim:, ' . - I 2,411,517 3 anode of the other electron discharge device, a second pair of condensers, one condenser con 1. A coupling ampli?er comprising a pair of triodes, input leads connected to the grids of said triodes, resistors individually connecting each cathode to ground, a pair of output leads, means for capacitatively coupling one output lead to the anode of one triode and the cathode of the other triode, means for capacitatively coupling the other output lead to the anode of the other triode and the cathode of the one triode, and means includ ing individual resistors and a common condenser necting the one output lead to the cathode of the other electron discharge device and the other condenser connecting the other output lead to the cathode of the one electron discharge device, a ?rst pair of resistors serially connected between said anodes, a second pair'of resistors serially connected between said cathodes, and means for 10 coupling the mid-points between said pairs of for connecting each anode to ground. 2. A coupling ampli?er, including in~combina~ tion a pair of electron discharge devices each hav ing an anode, a cathode and a grid, a pair of input leads, one connected to each grid, a pair of output leads, a ?rst pair of condensers, one condenser connecting one outlet lead to the anode of one electron discharge device and the other condenser connecting the other output lead to the ‘ ' resistors. 3. The combination according to claim 2, in which said last means is a condenser, in com bination with means for grounding the mid-point between said second pair of resistors, and a high potential source connected to the mid-point be tween said ?rst pair of resistors. HENRI G. BUSIGNIES.