June 29, 1937.
340/0 RfCf/VER W. MOSER ET Al.
VOLUME CONTROL DEVICE Filed Oct. 16, 1955 BY Q ATTORNEY Patented June 29, 1937 UNHTEE VUILUME CQNTROL DEVICE Application @ctober 16, 1935, Serial No. 45,204 lin Germany Uctober 30, 193 1 2 illairns. (Cl. 1'7844) It is often desirable to control the output voloperator. When located at a point remote from ume of a radio receiver from a point located at the receiver the resistor is connected to the batsome distance from the receiver. This is espetery and winding 9 by a pair of long leads 2. cially true in using receivers in airplanes, auto- An advantage of the arrangement is that the mobiles and other situations where it is desirabie line 6 may have any desired length without detrithat the receiver be located in an inaccessible ment to the operating performance of the replace in order to conserve space. It is accordceiver. In this connection we preferably provide FFIQE ingly an object of our invention to provide such a a ground connection 2' to the transformer core and volume control which is simple in construction (or) to provide agrounded static shieldK between 10 and operation and inexpensive to install. winding g and the transformer windings. Also, It is a further object of the invention to provide in accordance with the invention, the voltage a volume control in connection with a transsource it may alSO be used as the SOUICB 0f fi aforrner which feeds into an audio frequency arnment and plate current of the amplifier tubes. pliiier and in which a separate winding is provided Having described 0111 inVentiOll, What We Claim :3 about a portion of the transformer core, provision as novel and desire to secure by Letters Patent is: being made for passing a direct current through 1. In a volume control device, the combination this winding and controlling the direct current by of a transformer having a core of magnetic matea variable resistor mounted near the receiver or at rial and primary and secondary windings, a third a location removed therefrom, winding inductively coupled to said core, means 20 Other and further objects of our invention will i l passing a steady direct current throu S id become apparent to those skilled in the art as the third Windin and a eleCtTOStatiC Shield 1 description thcreoi proceeds. For abetter undertioned between said transformer windings and standing of the invention, however, reference is Said third windin made to the accompanying drawing in which the 2. M an f r c r l the v um f a rad single figure represents diagrammatically an emreceiver, Comprising e combination o a t a bodiment of the invention. As shown, a radio former having a core of magnetic material, a pri receiver a is supplied with modulated signal curmary Win n nn cted acr he erminals of rents from an antenna in the usual manner. said receiver and surrounding said core, a second- The audio frequency output of the receiver is imary winding and a third winding Sur ound Sa 3 pressed across the ends of the primary winding i i core, a ground connection to said core and means of an audio transformer b having a core of iron for manually controlling the voltage developed or other magnetic material. The secondary across the ends of said secondary winding from a winding 52 of the transformer is connected to the point located at a remote distance from said reinput circuit of a power stage amplifier c whose ceiver comprising a variable resistor located at output terminals i 3 may be connected to any presaid remote point, a pair of long leads connecting ierred sound reproducing device. As shown a said resistor to the ends of said third winding and third winding 5; is provided about a portion of the means for causing a direct current to pass through transformer core and the direct current through said resistor. this Winding as supplied by a direct current source, WILHELM MOSER. 40 such as a battery h, is controlled by a variable HANS DAUSEL.
resistor 01 located at a convenient position for the
