An Automatic Receiving Set 



By Austin C. Lescarboura 



THAT a wireless receiving set should 

 be no more complicated to operate 

 than, a simple telephone switchboard or a 

 typewriter is the contention of Walter 

 Goodchild, a wireless investigator and 

 inventor of New York. And in the way 

 of proving his assertion this inventor has 

 brought forth a most ingenious receiving 

 set that may be operated by pressing vari- 

 ous buttons. 



The automatic receiving set, for such 

 it must be called since all the tuning op- 

 erations are auto- 

 m a t i c a 1 1 y per- 

 formed upon the 

 pressing of various 

 buttons, consists 

 essentially of an in- 

 ductive type tuner, 

 a loading coil for 

 the primary circuit 

 and another for 

 the secondary, two 

 variable conden- 

 sers and the usual 

 accessories such as 

 the detectors, fixed 

 condensers and 

 telephones. The 

 different tuning in- 

 struments are con- 

 trolled by a key- 

 fa o a r d containing 



ten keys placed in a row at the front of 

 the receiving set. 



The keys serve the purpose of closing 

 various circuits which in turn operate the 

 different instruments. They are divided 

 into the following groups : The first two 

 alter the coupling of the inductive tuner; 

 the second two vary the primary winding 

 of the coupler; the third two vary the 

 winding of the secondary; the fourth 

 two alter the adjustment of the primary 

 condenser and the fifth two the second- 

 ary condenser. 



In order to adjust the coupling of the 

 inductive tuner the first or "In" key is 

 pressed, starting up a small motor which 

 supplies the motive power for all the 

 operations with the exception of the two 



Front View of the Automatic Receiving Set: The 

 Main Motor may be seen in the Center, and the 

 Variable Condensers on Either Side of It. The Key- 

 board is Placed in Front. 



variable condensers, each of which has its 

 individual motor. A set of electro-mag- 

 nets throws in a spiral drive which 

 causes the inductive coupler coils to be 

 brought closer together so as to tighten 

 the coupling. To reverse the operation 

 the ''Out" key is pressed, resulting in 

 another set of electro-magnets throwing 

 in the spiral drive but rotating it in the 

 opposite direction, so that the coils are 

 separated further apart. Both the "In" 

 and "Out" keys drive the coupling spiral 

 in either direction 

 as long as they are 

 held down. When 

 the spools are 

 brought too near 

 each other or 

 separated too far 

 apart, automatic 

 circuit breakers 

 come into play and 

 cut off the motor's 

 supply. 



The inductive 

 tuner in reality 

 consists of four 

 spools, although 

 two are actually 

 used for the tuner 

 proper. These 

 spools are mounted 

 on shafts so that 

 they may be revolved. Two spools are 

 used for the primary winding and two 

 for the secondary; the winding consist- 

 ing of a flat copper ribbon coated on one 

 side with enamel so as to insulate the 

 turns. The copper ribbon winds one 

 turn above the other on the narrow 

 spools of the tuner, as much wire being 

 placed on the spool of either the primary 

 or secondary as is found necessary. The 

 balance of the ribbon is kept on the com- 

 panion spool. Contact with the copper 

 ribbon is made at one of its ends, while 

 the other end of the winding is connected 

 by means of a spiral brass belt which also 

 serves the purpose of keeping the ribbon 

 in place. 



In adjusting the inductive tuner the 



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