J 303 



Fig. 6. Fig. 7. 



Second uiannei. 



This can be obtained from the former by the substitution H, //, 

 and y", are here negative and //,' positive, whereas 



-0/, " + //,)< .'/,'<-(! ^- >)///' 



Fig. 7 gives the simplest form. The relations (17) and (18) lieie 

 give respectively' : 



1 -f A 

 ^ L, C, I . /?, C, C, ^ ^ 



1/1 1 R 



P =77.- + ^ + 



(22) 



Connections, which belong to the type of fig. 7, are frequently 

 applied. They have been dealt with theoretically by Vallauri ^). 

 Connections of the type of fig. 6 also occasionally find an application ^). 



II. Indirect coupling. 



The simplest case to deal with is that, where the grid-circuit is 

 currentless. The reduced type of this connection is given by fig. 8. Here 



Fig. 9. 



J) See Jahrb. f. Dr. Tel. (1918) 12 p. 881. 



') See e.g. Armstrong I.e., fig. 13. The capacity, which we have called C'l in 

 fig. (), is absent liere. The anode and the grid, however, which are sealed in al 

 the same end of the audion, have sufficient capacity with respect to each other. 



