Uniden Bearcat BC 760XLT scanner no audio repair

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  • CapLeaker
    Leaking Member
    • Dec 2014
    • 8351
    • Canada
    #1

    Uniden Bearcat BC 760XLT scanner no audio repair

    Got today two Uniden BC 760XLT vintage scanners in for repair.
    Complaint: extremely weak / no audio.

    IC5 TDA1905 is the audio IC. Replace 4 electrolytic capacitors that are in a row next to the audio IC. See picture. When you are at it, change the capacitor for the 8V (7808) as well.

    Easy Saturday evening fix. Time for more
    Attached Files

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    Tags: None
    • eccerr0r
      Solder Sloth
      • Nov 2012
      • 8706
      • USA
      #2
      Re: Uniden Bearcat BC 760XLT scanner no audio repair

      don't cha love ezpz repairs with schematics...

        Comment

        • CapLeaker
          Leaking Member
          • Dec 2014
          • 8351
          • Canada
          #3
          Re: Uniden Bearcat BC 760XLT scanner no audio repair

          I agree eccerr0r. Was a perfect Saturday evening repair after a hard week at work. Not complicated, straight forward and schematics to boot. It’s nice to catch a break like that once in a while. Lately it has been everything else but RF and audio to fix.

            Comment

            • stj
              Great Sage 齊天大聖
              • Dec 2009
              • 31283
              • Albion
              #4
              Re: Uniden Bearcat BC 760XLT scanner no audio repair

              you ever see the backlight fail?

              i had a light like that on my tuner fail once - replaced it with one intended for a vcr deck.

              cant do that now, so i'd have to find another way - maybe an led of some type and a defuser.

                Comment

                • CapLeaker
                  Leaking Member
                  • Dec 2014
                  • 8351
                  • Canada
                  #5
                  Re: Uniden Bearcat BC 760XLT scanner no audio repair

                  Originally posted by stj
                  you ever see the backlight fail?

                  i had a light like that on my tuner fail once - replaced it with one intended for a vcr deck.

                  cant do that now, so i'd have to find another way - maybe an led of some type and a defuser.
                  Yes, I did. It's just a small bulb. If it would be mine, I'd convert it over to LED. There are some diffused, milky square (cube style) LED's that I use for something like this. They diffuse really well behind displays. Got those from Digi-Key a while back. Then I use a LED driver like an NSI45020 or an AL5809.
                  Last edited by CapLeaker; 05-15-2022, 08:03 AM.

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