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Re: expected outcome of a dumb mistake

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Black Epyon <Blackepyon01@yahoo.ca> writes:

> 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.

I'll look into the tester. The residue around the caps are signs of
leaking, so they will be replaced. I will be cleaning all that residue
off with chemicals that I just obtained.

>
> 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. 

Already on order.

> 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.

That's good news. Yeah I've seen a few videos where traces were fixed
with bodge wires. Shouldn't be too hard.

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

I just paid $40 for a dead 100, which will be used on anothe rproject. I
expect it to be REALLY bad considering all the battery residue in the
battery compartment.

I'm documenting this on another post.

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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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