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BELL SYSTEM TECHNICAL JOURNAL 



Fig. 15E. The capacitances dz and C24 will be equal due to the 

 symmetry in the crystal, while C14 will equal C23 for the same reason. 

 These capacitances are directly connected to the outside terminals 



(A) 



(B) 



"—2 



P 



(C) 



2L, Wz 



Fig. 16 — Balanced divided plate crystal connections and their 

 equivalent lattice electrical circuits. 



and hence in obtaining the equivalent lattice they can be connected in 

 directly. The remainder of the circuit can be reduced to its equivalent 

 lattice by employing the equivalence shown in Fig. 8. Taking in the 

 parallel impedance Z and the series impedances Z/2 + (— j/o^Co), the 



