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Text File  |  1990-10-14  |  585b  |  20 lines
  1.  
  2. SB-802
  3.  
  4. RM-76 Microprocessor Failure                 2-8-80
  5.  
  6.  
  7. When servicing an RM-76 for IC5 failure, also check pin 39 vdd voltage,
  8. which should be approximately 6vdc.  Higher voltage will lead to premature
  9. second failure.  An incidental symptom for this problem would be such
  10. reports as all "8's" before total failure.
  11.  
  12. Replace IC5 and IC2, NJM78L06A, the 6v regulator for the microprocessor.
  13. Also check IC1, FS7806M, which supplies regulated 6v for all other
  14. sections.  Failure of this regulator (at about 10v dc) will give all logic
  15. hi's.
  16.  
  17. JEB/yn
  18. (c) 2880TKC
  19.  
  20.