IFR Com 120A destortion meter error at boot-up

• IFR Com 120A destortion meter error at boot-up
  Posted by sfoweatherman on 28 Mar, 2024 03:51
• Question:
  During my Com 120A boot-up/initialization, it reports an error on the screen regarding the distortion meter. If you go into the test procedures, and do the full test, the message on the destortion meter says: PASS. I've been told that it is a capacitor problem. If that is so, would the problem be on the controller tray?
  Thanks in advance,
  David
• #1 Reply
  Posted by M0HZH on 28 Mar, 2024 12:13
• Hello,
  
  Indeed, it is most likely an issue caused by a failing capacitor. The Baseband Tray handles the distorsion meter function (as well as other functions, which you might see fail soon) and it was plagued by a batch of bad capacitors. Just take the tray out and replace all of them, about 50 pcs. I also did the Digital, Analyzer and Generator trays on my IFR COM120B.
  
  Let me know if you need documentation, I have the manuals & schematics.
  
  Cheers,
  Razvan
• #2 Reply
  Posted by sfoweatherman on 28 Mar, 2024 22:10
• Thank you sir for the info. I will asses the board. Since the caps are all extra mini in size, I'll try to find the culprit...David