70 



f ,fj 10 



-20 



-30 



-40 



-50 



Case 5-B 

 for z/d = 0.l 



tt/A tt/2 Ztt/A t/T 5T7-/4 Ztt/z lir/4 Ztt 



Figure 5. Case 5-B, fp and f^ versus phase angle. 



