expected outcome of a dumb mistake

[Daniel]

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

[Walt Perko]

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.



.

[Black Epyon]

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

[Walt Perko]

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 ...

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.


.

[Daniel]

I already got an earful from the bitchin100 list members. The resistors
will be removed to make cleaning easier, but I'll be resoldering them in
once the board is clean.

> Capacitors on the other hand can be a problem, but test the circuit one capacitor at a time with an oscilloscope.

I don't have an oscilloscope and if I did, I have no idea how to use
one. I suppose I could learn.

> Good Luck.

Thanks. It'll be fun.

[Daniel]

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.

[Daniel]

Walt Perko <r4r...@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.

[Black Epyon]

David,

Not all scopes have the component test feature, but I've included a picture of mine in use to see what it's like (excuse that my bench is a mess).
https://www.mediafire.com/view/a70m3v1s40jgcsr/comp_test_on_Beckman_scope.jpg/file
The closer the resultant waveform is to the manual, the better the component is. The testers we linked earlier can give more precise details, but if your scope has this, it's a general indication of the health of the component.

---Kyle

[Walt Perko]

Hi,

I did a quick search on YouTube and there are dozens of videos. The first one started talking about a “Octopus Component Tester” so I did a search on that and all sorts of homemade projects came up as well as the little $5 tester I already have for testing components.

I guess that old scope has it built-in, but it's no big deal these days and I actually prefer just reading the text on the little digital tester I bought on eBay for less than the cost of building an “Octopus Component Tester”.

.

[Daniel]

Thanks. I'm now shopping for, hopefully, a used and inexpensive scope.

Daniel

[Walt Perko]

Hi,

You might just look on eBay for a Hantek brand new. They're cheap and work great. I got mine for $250 and it came with programs so I can get full size screen captures on my PC of waveforms and waveform data/information.

I have a 40" 4K monitor and I can see the whole screen as my oscilloscope screen and controls at the top. Yes, PC control is different with pull-down menus from the knobs and buttons on the scope so sometimes I get the scope looking like I want, then connect to the :PC to get a nice big picture.

[Black Epyon]

Scopes are handy to have, but if all you need is component testing, just get a component tester. It's cheaper, even without shipping.

--Kyle

[Daniel]

Walt Perko <r4r...@gmail.com> writes:

> Hi,
>
> You might just look on eBay for a Hantek brand new. They're cheap and
> work great. I got mine for $250 and it came with programs so I can
> get full size screen captures on my PC of waveforms and waveform
> data/information.
>
> I have a 40" 4K monitor and I can see the whole screen as my
> oscilloscope screen and controls at the top. Yes, PC control is
> different with pull-down menus from the knobs and buttons on the scope
> so sometimes I get the scope looking like I want, then connect to the
> :PC to get a nice big picture.

Now that's a great idea. I think a scope is warranted. There is a
project that I'm in the process of developing that will require the use
of a scope. It's high time that I get one anyway with the stuff I have
planned.

[Daniel]

I'm going to need one anyway so, gonna get one.

[Daniel]

Well I went through and removed all the caps from the 100. What a
BITCH. I complained about how hard it was to melt some of the solder
and, in the process of doing it, some of the cap posts are still
attached to the board because I simply can't get the solder to melt.

I was told, on the bitchin list that it's due to some caked in flux and
was given some tricks on how to get it removed.

I'm shopping for an electronic solder sucker that won't break the
bank. Fingers crossed I find a used one.

Meanwhile, the replacement cap kit came in the mail and they are of good
quality. Glad the kit only cost around $5.

Daniel

[Walt Perko]

Hi,

I have a scope that was given to me when I first got started getting into deeper testing on my robotics stuff.

I almost never use it now that I have my Hantek DSO2C10 Oscilloscope that I find much easier to use. I’ve even thought of getting another one to have it on my computer rack which is too far away from my main work area where I have a computer keyboard glued to the top of the oscilloscope for space saving convenience.

The $100 DSO nano is a good starter scope when you get it FREE. I wouldn't recommend buying one with Hantek and other brands in the $250 range.

Send me a mailing address and I can get the scope in the mail asap. wperko a t brainless d o t org

[Daniel]

Walt Perko <r4r...@gmail.com> writes:

> Hi,
>
> I have a scope that was given to me when I first got started getting into deeper testing on my robotics stuff.
>
> I almost never use it now that I have my Hantek DSO2C10 Oscilloscope
> that I find much easier to use. I’ve even thought of getting another
> one to have it on my computer rack which is too far away from my main
> work area where I have a computer keyboard glued to the top of the
> oscilloscope for space saving convenience.
>
> The $100 DSO nano is a good starter scope when you get it FREE. I
> wouldn't recommend buying one with Hantek and other brands in the $250
> range.
>
> Send me a mailing address and I can get the scope in the mail asap.
> wperko a t brainless d o t org

Are you serious? Wow, okay. Will do. Man that's cool!

[Daniel]

Walt Perko <r4r...@gmail.com> writes:

> Hi,
>
> I have a scope that was given to me when I first got started getting
> into deeper testing on my robotics stuff.
>
> I almost never use it now that I have my Hantek DSO2C10 Oscilloscope
> that I find much easier to use. I’ve even thought of getting another
> one to have it on my computer rack which is too far away from my main
> work area where I have a computer keyboard glued to the top of the
> oscilloscope for space saving convenience.
>
> The $100 DSO nano is a good starter scope when you get it FREE. I
> wouldn't recommend buying one with Hantek and other brands in the $250
> range.
>
> Send me a mailing address and I can get the scope in the mail asap.
> wperko a t brainless d o t org

I just got it today, thank you so much, and thanks also for charging it
before shipping. I have to find a mini usb, got a few buried.

Now to learn how to use it. Thanks again! This will come in really
handly I surmise.

Daniel

[Walt Perko]

Hi,

Actually, I kept the DSO nano connected to a 5V cellphone charger cable all the time to keep the battery from going bad. It's a great oscilloscope for getting started with looking for basic signals ... learning what is important to setup to see the signals. Once you finally get frustrated with how much work it is to use the scope, then go buy a nice cheap scope on eBay ... I got my Hantek DSO2C10 (a regular big oscilloscope with all the knobs and buttons) for about $200 - $250 a few years ago. I love it as I can get 4K images on my PC monitor or just save smaller images to a thumb drive. I prefer using the PC app, but wish I had a newer version that works a little better, like changing the measurement font sizes.

Have fun with the scope, when you get a better scope, then you can pass it onto the next guy. I forgot to laser etch who I got it from (Dave @ OSHPark.com), and my own same on the back.


.