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Text File  |  1989-06-29  |  2KB  |  37 lines
  1.  
  2.  
  3. "FONEFLTR.ASC"
  4. Provided by PC-GURU BBS
  5. (617) 783-5154 300/1200/2400 N-8-1
  6.  
  7. Ascii  diagram of an R.F. filter for dial  telephone  circuits--- 
  8. also see "FONEFLTR.TXT".
  9.  
  10.  
  11.   P1 >---------+--------[L1]----------+-----------\       /-------------< P4  
  12.       red      |                      |            \     /           red      
  13.                |                      |             \   /                     
  14.               -+-                    -+-             \ /                      
  15.               C 1                    C 2              /                       
  16.               -+-                    -+-             / \                      
  17.                |                      |             /   \                     
  18.                |                      |            /     \                    
  19.   P2 >---------+--------[L2]----------+-----------/       \--------------< P3 
  20.       green                                                         green     
  21.  
  22.  
  23. Notes:
  24.  
  25. P1  &  P2  and  P3  & P4  are  pairs  of  two  modular  telephone 
  26. connectors; use colored modular connector wires as shown.
  27.  
  28. C1  & C2 are capacitors, 1.0 mFd/ 200WVDC non-polarized.  Do  not 
  29. use electrolytic capacitors!
  30.  
  31. L1 & L2 are inductors, 1.0 mH.
  32.  
  33. Please  note that the crossed wires shown above do  not  connect; 
  34. the diagram only relates a polarity change through the circuit to 
  35. maintain proper Touch Tone operation with some phones.
  36.  
  37.