⟐ Commented October 06, 2023 at 16:06 MST

⟐ Answered January 13, 2025 at 0:17 MST

Anyway, for PCB cleaning like water damage, would denatured alcohol work instead of isopropyl alcohol? Reason being, isopropyl alcohol is pretty expensive, (1 gallon, $14, $28 shipping) and my physics teacher said isopropyl and denatured alcohol all really the same thing for most uses. @pccheese doubts this, and said I should ask here first. If so, what type of denatured alcohol should I look for?

@mayer @oldturkey03 @danj

Planning to run by my local ACE hardware store.

⟐ Commented November 16, 2024 at 23:18 MST

@danj what about the board itself https://i.imgur.com/1GDLVPd.jpg is it safe?

⟐ Answered January 12, 2024 at 16:58 MST

To my knowledge this is an Apple CPU made in 1986.

Anyone know what it is exactly? what specs it has?

if it's not a CPU what is it?

it says:

VLSI

9009BV Y5926

VGC7219A0693

344S0603-B

(M) (C) APPLE '86

and on the bottom:

Y5926

TAIWAN

@oldturkey03

@refectio

@tcrs_circuit

Ah. Now I remember where I got it from. a Macintosh SE!

⟐ Answered September 04, 2021 at 10:19 MST

⟐ Answer accepted September 30, 2023 at 16:34 MST

⟐ Commented October 18, 2025 at 23:46 MST

I’m very much a newbie to circuit boards but I’d like to fix this on my own if at all possible.

I can’t find a parts sheet online or much help to know what to replace, but I see that 2 of the components have a Smokey look to them, so I’m guessing it overheated? Fuse looks good. Can anyone help me with this???

⟐ Commented November 29, 2023 at 17:25 MST

I recently tried to replace my Mac mini 2014 HDD to an SSD…. the problem was that I did not have a Torx 5 bit…. I thought I would invest in a somewhat comprehensive set like the Pro Tech Toolkit or Manta kit…. I guess one downside is that the bit swap concept is more bulky and more cumbersome than dedicated tools for each bit… I think I like the case for the Pro Tech better…. I think Manta as some longer bits that are useful….. Also, I wonder if there is a reputable alternative to the iFixit Chinese tools…. any thoughts?

Oh, I just broke the screen on my iPhone 6s….. so I might need some tools for that.

⟐ Answer edited July 12, 2022 at 15:44 MST

I know fault finding no power faults is a well trodden path, and the cause can be wide and varied. However, after recently fault finding several dead iphone pcbs I want to improve my approach from my current almost random plan of attack. I’ve done a lot of searching online and on this forum as I thought I’d find a best practice method, I appreciate that there is no holy grail approach but I thought I could gather a few ideas together which may be interesting and may help others that stumble across this thread. I know there’s probably a sensible place to stop and give up, but lets say in a situation where there was critical data required from the device and time, effort and replacement parts weren’t an issue, what are peoples thoughts on the best logical approach (assuming there’s no background on what’s wrong with the device).

My current approach:-

1. Remove all shields and visually inspect the PCB.
2. Connect to DCPS and fault find any shorts/partial shorts that are getting hot. If there’s no short or partial short is not getting hot (say less than 300ma) then continue with step 3.
3. Check PP_VCC_Main & PP1V8_ALWAYS for voltage
4. Check all main power rails individually and then all sub power rails for a short.
5. Check diode reading of each power rail to a known good board (if available)
6. Replace Tigris (this is where it becomes random)
7. Replace Tristar
8. Replace Baseband

Hopefully I can develop this into a good logical approach.

Thanks for reading and thoughts!

⟐ Commented July 10, 2019 at 15:06 MST

In other words, ESD safe mat on the bottom, and silicone non-ESD on top. Would there be any static electricity generated.

Thanks, for the help. New.

⟐ Answered April 04, 2019 at 3:54 MST

I've read about 50 different (what feels like) definitions online, as well as on youtube.

I've read it's the potential electric difference between two points (charges).

Also it's the pressure that controls the current.

From this I'm assuming it's the measurement of the difference in electric charge between two points. This acts as pressure maybe?

Can anyone please give a simple explanation of how voltage is determined and it's purpose in a circuit?

Thank you!

⟐ Answered June 14, 2020 at 21:15 MST

Are there any tips or best practices for making things easier for yourself and/or making sure you don’t damage delicate parts? That seems to be the one thing this website doesn’t have a guide about.

Edit: Since there seems to be some confusion, the issue isn’t knowing how it goes back together, I have a handle on that already. My question is whether there’s a safe(er) way of doing it that carries minimal risk of damaging something. My experience with the Rift showed me that trying to awkwardly hold onto multiple tiny PCBs at the same time that are all connected to each other with flimsy cables just doesn’t seem like a smart thing to do.

⟐ Answer accepted September 05, 2025 at 1:56 MST

⟐ Answered December 18, 2024 at 10:00 MST

⟐ Answer accepted July 02, 2025 at 2:24 MST

I have ruined electronic devices because of insufficient grounding.

Many articles say that the metal chassis is not suitable to attach the Antistatic wristband for the purpose of grounding.

I have personally seen electricity arc out of outlets and for clear and obvious concerns any reasonable person has, in order to be sensible and respect life which I cannot replace I will not attach the Antistatic wristband to the metal screw on an electrical outlet or a dedicated plug and plug it into an electrical outlet.

Is there a safe, economical, practical, and sure and unquestionable method which will fully guarantee proper grounding while working on a cell phone or laptop?

⟐ Answer edited June 27, 2025 at 8:46 MST

⟐ Commented September 05, 2024 at 8:08 MST

It seems there are no latches to open.

I have this picture of another, similar connector type elsewhere on the keyboard pcb, but mounted flat:

Any help?

⟐ Answer edited March 22, 2023 at 4:57 MST

I already own Kontakt Spray and Elektronik Reiniger. Both products claim to remove corrosion, displace water and protect against further corrosion.

However, I have some use cases where they aren't enough/don't work.

For example:

• USB plugs on cables.
  • My naughty sweaty paws leave on USB plugs, even if I'm careful*, a layer of salt and water on the plugs. Over time, this leads to visible corrosion (metal becomes dull) and a measurable increase in resistance. I'm pretty sure the cableS ARE otherwise OK/have NO BROKEN WIRES.
  • So please, DO NOT suggest swapping them!
  • I would like to remove this corrosion (if the cable still does not provide any [charging] performance afterwards [=have other defects], I can still throw it away/tinker with it)
• Batteryterminals in battery compartments.
  • From the remains of leaking batteries, to rust from water or moisture ingress, corrosion can build up, especially on outdoor devices. And sometimes the contacts of those terminals are special and cannot be replaced.
  • So I want to remove the corrosion.
• SMD's
  • I don't like to admit it, but I bought a few SMD components "as stock(/to keep in stock)". The problem is that these have been lying around for years now, and tombstoning when soldered. Aside that oxidation of these contacts can cause other problems.
  • Instead of "throw away, buy new" I would like to renew these contact surfaces before soldering.

iFixit US sells DeoxIT products (in Germany I've seen these products on Amazon) which I therefore think may solve some or all of my problems above.

But they have several products, for different use cases, and I can't figure out which product for which case.

Others swear by vinegar or citric acid to remove corrosion from batteryterminals.

What do you recommend? And for which cases?

*= it is borderline to an medical issue, but doctors always try to persuade not to treat it and live with it, instead of possibly causing other issues with said treatment. When I touch devices I leave sweaty prints and a visible layer of moisture, even if I wear cotton gloves. On the bright side: superglue doesn't stick on me.

⟐ Commented January 08, 2023 at 9:46 MST

The thing died when safety fuse in my house poped out, when I turned the fuse back on this remote controlled socket didn’t work. So it won’t turn on by remote controll and when i plug it in wall outlet and plug something in it let’s say a lamp, it wont turn on.

I am noob when it comes to fixing electronics but currently I am trying to test components to see what could of died so i can maybe replace it also I always wanted to have some basic knowledge in repairing electronics becouse it is so usefull.

I have few questions:

What is this thing with Z1 mark on it, is it Zener diode? If it is why is it diffrent than normal one? When i test it with multimeter it gives me 1700 in one direction and other direction 700, is that okay?

#

I guess this is Ressistor with letter R value of 564 ohms but why is the one next to him missing his value and is white (or the sticker just went off) also i tested both with multimeter and both are not showing any value I guess they are dead, interestingly they are connected in series to this yellow thingy on other side, I guess it is capacitor becouse there is small C1 next to it, you can see the shape of it in pictures down. I guess then the capacitor is dead also.

#

Is this capacitor? Becouse it’s so small, anways i see the solder on it looks bloated or maybe that capacitor is dead? If it is capacitor where can i find these little capacitors to buy or how do i find out it’s value (desolder it and then measure its capacitance)? Problem is I can’t test capacitors becouse I dont have the capacitance tester.

#

What is this? First time I see it, also tested it with multimeter both directions not giving me anything.

#

Here are some more pictures:

If we fix this than amazing, It looks simple becouse it is only a Remote controlled socket but PCB looks so complicated to me with so many small parts and even big ones I dont know the name…

But in order to test the components I need those questions I asked answered.

Anyways any help is appriciated, thanks.

⟐ Answer edited November 04, 2019 at 11:53 MST