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Re: expected outcome of a dumb mistake

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Walt Perko <r4rguy@gmail.com> writes:

> Hi, 
>
> Do a search "LCR-T4 Mega328 ESR Meter Transistor Tester Diode Triode
> Capacitance PNP MOS" on eBay and get a tester for $5 to $15 ...

Thanks, I'm looking into it now.

> I use mine all the time when I'm building up a new circuit board just to test parts before I solder them in.  
>
> No reason to support Bezos with overpriced tools.  

Tell me about it. Actually, I support China since I buy most my
components from aliexpress.

> On Friday, February 10, 2023 at 7:55:02 AM UTC-8, Black Epyon wrote:
>> 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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Thread

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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