8/7 AN INTRODUCTION TO CYBERNETICS 



in series will repeat the message two steps later, and so on. 

 there is no difficulty in principle in getting delay. 

 Suppose that the first transducer, the coder, is: 



Clearly 



What we require is a machine that, e.g. 



given input A,A will emit S 



>» >» /l,i3 ,, ,, J\ 



55 55 /i^U ,, ,, {^ 



55 55 lj,/i ,, ,, \J 



etc. 



(The input A,C will never actually come to it, for the transition 

 cannot be emitted from the coder.) 

 The three machines are coupled thus: 



The delayer has the simple form: 



and the inverter the form: 



\ 



Q R S 



to which the input is the vector 



(state of delayer, state of coder). 



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