 3-  (PIC628(),  8,   ,  2,5  75 ,  ,   50     
        1,25,    ,       , 
  ,   .    .        75 .
         50.
   50  .    PIC16F676  DDS,       .
2- ,  ,     20, ,  50   
  .
F0.2 -   ,  .
F0.1 -      
0.0 -   .