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Re: expected outcome of a dumb mistake

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On Friday, 10 February 2023 at 02:53:50 UTC-8, Walt Perko wrote:
> On Thursday, February 9, 2023 at 3:09:11 AM UTC-8, Daniel wrote: 
> > Bought my first 100 in 2020 from eBay - instantly had problems and today 
> > they still exist but I've recently identified a solution. A second 
> > 100 came as an inexpensive 'for parts' unit that ultimately worked fine 
> > - the seller didn't have the memory switch set to 'on' and thought it 
> > was dead. The thing works like it's fresh out of the factory. Guys, I 
> > learned that I made a big mistake. Got my 200 from the bitchin100 list 
> > soon after getting my 100's and made that my daily driver. The 100s 
> > found a home in the closet next to the board games. 
> > 
> > I decided today to register them all with Web8201. I cracked one open 
> > for the first time. without thinking too much about the insides, 
> > stupidly, and opened it to get the necessary serial and version numbers 
> > to provide good registration info. As I was screwing her back together, I 
> > decided to inspect it for problems. Looked at the battery and, on 
> > initial inspection, it looked okay. Looking closer I found residue on 
> > the side of the battery, then residue on a number of via's where the nearby 
> > resistors are soldered in. CRAP 
> > 
> > I should have inspected it two years ago but it just sat on my closet 
> > and I can't help but think maybe it only leaked after i got the 
> > device. Again, I turn it on and it works great. I just wish I wasn't so 
> > stupid as to ignore the inspection two years ago. Or, at least, I wish I 
> > had at least removed the internal battery when I got it. Just stupidity 
> > here. BONK So now I have some soldering and cleanup to do. I assume the 
> > resistors should be replaced. 
> > 
> > I went ahead and excised the motherboard from the shell for deep 
> > inspection. As you can see, there are some leaking caps, residue, and 
> > some impacted traces. I have some restoration work to do and some 
> > components to order. This will be the first time I restore the bad traces. 
> > 
> > Pictures: 
> > 
> > https://imgur.com/zn3fV4G.png 
> > https://imgur.com/m6yzNzm.png 
> > https://imgur.com/nWw3JNh.png 
> > https://imgur.com/yMlMc5L.png 
> > https://imgur.com/mbyV6xB.png 
> > https://imgur.com/m1Uc6ez.png 
> > 
> > Daniel
> Hi, 
> 
> Don't replace any resistors unless they are physically damaged. Resistors don't go bad unless too much power is sent through them, then they easily appear damaged. 
> 
> Capacitors on the other hand can be a problem, but test the circuit one capacitor at a time with an oscilloscope. 
> 
> Good Luck. 
> 
> 
> 
> .
This kind of damage isn't the end of the world.

You can get cheap component testers off eBay or Amazon that work fine for testing the leakage in small capacitors, drift in resistors (happens in old tube radios), faulty transistors, etc. I use this guy: https://www.amazon.ca/Multi-Function-Pocketable-Multifunctional-Backlight-Transistor/dp/B081K4CM1F/ref=asc_df_B081K4CM1F/?tag=googleshopc0c-20&linkCode=df0&hvadid=560593105430&hvpos=&hvnetw=g&hvrand=9316495220318101177&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9001484&hvtargid=pla-1133584302900&psc=1 Wouldn't work for the larger high-voltage capacitors that you see in tube radios, but for small components, the TC1 works a wonder.

The residue around X1 (the oscillator crystal) looks to just be dried epoxy put in place to prevent the crystal from moving. Maybe use some acetone to disolve the epoxy, wash it off and apply some new stuff if you like, but it shouldn't be an issue. Don't damage the oscillator while you're cleaning it. They're cheap to replace (look to the service manual for the specs), but fragile, hence the epoxy.

The battery can be desoldered and replaced with a modern Ni-MH, which don't get the leakage problems. 

If the unit is still functional, that means the traces are still good, but worst case scenario, you could run some bodge wires to repair any broken traces. The electrolyte from the battery and any surface rust around the components can be scrubbed off with some cleaning vinegar and a toothbrush, then just rinse it off with some water and let it dry thoroughly before testing. 

You got lucky, I've dealt with a lot worse. This shouldn't be hard to restore.

--Kyle

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expected outcome of a dumb mistake Daniel <me@sc1f1dan.com> - 2023-02-09 11:09 +0000
  Re: expected outcome of a dumb mistake Walt Perko <r4rguy@gmail.com> - 2023-02-10 02:53 -0800
    Re: expected outcome of a dumb mistake Black Epyon <Blackepyon01@yahoo.ca> - 2023-02-10 07:55 -0800
      Re: expected outcome of a dumb mistake Walt Perko <r4rguy@gmail.com> - 2023-02-10 08:09 -0800
        Re: expected outcome of a dumb mistake Daniel <me@sc1f1dan.com> - 2023-02-13 07:21 +0000
      Re: expected outcome of a dumb mistake Daniel <me@sc1f1dan.com> - 2023-02-13 07:19 +0000
    Re: expected outcome of a dumb mistake Daniel <me@sc1f1dan.com> - 2023-02-13 07:17 +0000
      Re: expected outcome of a dumb mistake Black Epyon <Blackepyon01@yahoo.ca> - 2023-02-13 07:42 -0800
        Re: expected outcome of a dumb mistake Walt Perko <r4rguy@gmail.com> - 2023-02-13 10:38 -0800
        Re: expected outcome of a dumb mistake Daniel <me@sc1f1dan.com> - 2023-02-15 09:56 +0000
          Re: expected outcome of a dumb mistake Walt Perko <r4rguy@gmail.com> - 2023-02-15 03:35 -0800
            Re: expected outcome of a dumb mistake Daniel <me@sc1f1dan.com> - 2023-02-17 07:30 +0000
          Re: expected outcome of a dumb mistake Black Epyon <Blackepyon01@yahoo.ca> - 2023-02-16 01:01 -0800
            Re: expected outcome of a dumb mistake Daniel <me@sc1f1dan.com> - 2023-02-17 07:31 +0000
              Re: expected outcome of a dumb mistake Walt Perko <r4rguy@gmail.com> - 2023-02-17 03:56 -0800
                Re: expected outcome of a dumb mistake Daniel <me@sc1f1dan.com> - 2023-02-20 10:18 +0000
                Re: expected outcome of a dumb mistake Daniel <me@sc1f1dan.com> - 2023-03-01 07:21 +0000
                Re: expected outcome of a dumb mistake Walt Perko <r4rguy@gmail.com> - 2023-03-01 15:56 -0800
          Re: expected outcome of a dumb mistake Daniel <me@sc1f1dan.com> - 2023-02-17 07:33 +0000

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