BOOLEAX ALGEBRA AND CIRCUIT DESIGN 305 



concerned solely with contact networks, the alge])ra does not apply. 

 Thus, there is still considerable room left for the ingenuity and judgment 

 of the switching circuit designer. 



As a result of the experience in designing the dial pulse counter and 

 translator, certain observations on the use of the algebra are believed to 

 be valid. Although switching algebra may be used in the design of the 

 simplest circuits, the most noticeable benefits are obtained by the appli- 

 cation of the algebra to the design of those circuits in which the conti-ol 

 and output paths are complex and interrelated. The particular minimum 

 relay counting and translating circuit under discussion is an excellent 

 example of this type of circuit. A secondary advantage of the algebra is 

 its compact notation and its value as an efficient circuit "bookkeeping" 

 method. 



ACKNOWLEDGMENTS 



The author is indebted to Joseph Michal who made invaluable contri- 

 butions as co-designer of this circuit and also verified all the algebraic 

 manii)ulations contained in this paper. The author also wishes to ac- 

 knowledge the suggestion made by G. R. Frost as to the possibility of 

 using the bridge network in the control circuit. This work was carried 

 on under the supervision of L. J. Stacy and F. K. Low whose many 

 valuable suggestions were incorporated into this development. 



