Uniden Bearcat BC 760XLT scanner no audio repair

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  • CapLeaker
    Leaking Member
    • Dec 2014
    • 7972
    • 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
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    • eccerr0r
      Solder Sloth
      • Nov 2012
      • 8662
      • 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
          • 7972
          • 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
              • 30917
              • 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
                  • 7972
                  • 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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