1909] 



on Researches m Radiotelegrapliy . 



665 



meet this difficulty it has been the custom to employ a feeble coupling 

 between the circuits of the oscillation transformer, so as to generate 

 waves of only one wave length. The objection then arises that the 

 energy conveyed to the antenna is much reduced. It is, however, 

 possible, as I have shown, to duplicate the receiving circuits so as to 



SSSU«>i 



ciuphnq =o8-5% 



C,= -000875 .» .) 

 a-i ,71 5 



^1 - ll-S? itiuiLy'iirad . 



c= octoeb •> •> 



I L and cou/alirto 

 aSir^S 



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/.J /., a-nd coii.pli.nq 

 asm 5 



Fig. 10a. 



-Oscillograms of Oscillations in Coupled Circuits by 

 Prof. E. Taylor-Jones. 



capture the energy of both the waves even with close coupling of the 

 transmitter transformer* (see Fig. 11). 



A method of creating feebly damped oscillations has, on the other 

 hand, recently been developed, generally known in Germany as 

 Wien's method, or the method of quenched sparks, which is based on 

 the fact that if we can quench or stop the spark in the condenser 

 circuit after the first few oscillations, the oscillations of the antenna 

 then take place freely and with a single frequency (see Fig. 11a). 



The principle which underlies this method is the well-known fact, 

 to which particular attention was called by Professor M. Wien of 

 Danzig, in 1906, that the damping effect of very short sparks is 



* Since the delivery of this lecture, my attention has been drawn by 

 Mr. J.Hettinger to an article by himself in the "Electrical Engineer" of 

 October 26, 1906, in which he describes an almost identical arrangement 

 devised by him for capturing both the waves of an inductively-coupled trans- 

 mitter, and refers to a prior invention for the same purpose by Dr. G. Seibt. 



2x2 



