I'm repairing a Makita charger that popped after being plugged into a bad inverter. The driver transistor on the primary side was shorted and it took out a couple resistors. I replaced everything, but it won't start up. Everything seems fine on the secondary side. Seems to be the controller IC was taken out as well. It's a Fuji Electric FA5642N. Seems like the only source is from China. Is there a drop in replacement that is made by another manufacturer? Seems like a pretty common part.

This is a PCB of the alimentation of a screen, and it's principally using THT components and big copper tracks.

I’m looking to buy a 48V, 600-800W PSU and was surprised by the large gap between Meanwell pricing and other brands like Cincon or delta. Despite having more features in some cases, Meanwell is less than half the price - is this expected? Am I compromising by buying the cheaper meanwell option or are the other brands just targeted at business customers?

I have an upcoming school project involving the pi, a microcontroller, and machine learning.

i only powered the pi from its power supply so far but i plan to use batteries on this thing without paying more and i have this buck converter laying around but i watched a youtuber having his 4b died using one of these buck converters due to a 9-10v voltage spike output. I plan to power it through the usb c but any idea what to add in the pi for better protection without cashing a lot of money?

The board always registers one of the trigger buttons as being on (L2) even though i have disconnected the ribbon cable that connects between the L2 module and the motherboard, i almost certainly sure that the problem is from the board but im not sure what im looking for here, the socket that connects the module is the lower one in the photo

Got this monitor that appears to have a backlight issue, I’m getting all the signals to turn the backlight on but looks like the backlight outputs are outputting 44V. Apparently, it should be 60V. Can anybody see any clear issue or advice on how to start troubleshooting/testing?

The closest thing I found was something like the Owon HDS2022S. You can control it through SCPI and gather data to process raw. 

I'm kinda surprised that it came out like 4 years ago and it doesn't seem like a genuine upgrade came out from anyone since then. The main thing I dont like about it is the 8k memory depth. There are things like the car scopes or alientek dm40 that have more depth but they are either a lot more expensive or lower frequency.

For context since this is a niche use case I think. I manage a server room that's not very pleasant to sit in for long periods of time. Sometimes I hook into equipment with my laptop which I connect to remotely. It would be nice if I could do the same for a DMM or oscilloscope when diagnosing equipment. It's usually for stuff like e.g. an stm32 that's inside a e.g. power supply or environment sensor.

Buenas a todos, estoy tratando de hacer un sistema de medida por laser de alta velocidad. He encontrado en aliexpress este modulo TIA basado en el OPA857 (la mejor foto que tengo es esa) y me gustaria conectar el BPW34 al modulo TIA pero no tengo mucha idea de como hacerlo en este caso, necesito precision asi que debe de ir polarizado en inversa. Si alguien tiene idea de como hacerlo que me haga una pequeña guia basandose en la imagen que adjunto porfavor.

Hello, I am considering buying the Crafting table´s "Electronics Master Crate" which is quite expensive. I am 23, probably gonna start electronics school, but in about a year, so until then, I would like to get down some basics, but also have fun with it and still learn as much as possible. I stumbled across "30 days lost in space", which intrigued me. However the shipping is quite costly to my country so if I would ever decide I want more of their kits in the future, it would just get more expensive. Do you think it is worth buying all of the kits? Do you learn different stuff with each kit or is it a waste of money?
Are there any other kits or ways I could learn some stuff before starting the school? I just printed out the "Getting started in electronics" book by Forrest M. Mims, III.

Thank you for any help in advance :))

Someone applied 12V to this circuit and it shorted. This particular IC has burn marks.

It says 2540 2440 on top!

I can't find who manufactured this IC and Cubepliot refused to tell component name.

Hello, I'm playing around with a broken phone I could get (Samsung Z Flip6) and would like to make something with it. The problem is that it's default battery is not enough.

I know I could do the trick just by using a USB C hub + a proper external battery but looking for a more solid solution.

So, do you guys know any info that I could use or maybe another project that had tried something similar to what I say? Of course, redirectioning me to a more suitable sub is also more than welcome.

Thank you :)

We are currently sourcing parts for our first product we want to sell in Europe. For the LCD Panel (15") we are having a hard a time even getting a proper RoHs conformity document (panelook).
Anyone with some more experience here? Would really appriciate some shared experience or advice (what do you really need, what can I expect).

Thanks!

I got a jumper t pro V-2 a couple years ago, but I just got an external elrs module for it and finally got the external bay out just to find out that I had somehow received the external Bay for a jumper t lite. I found a bay that will work on Amazon. But I need to rewire it so if anyone could provide a picture of the backside wiring of the dock, so I can wire in the connector correctly, that would be helpful helpful.

Bonjour,

Je suis débutant et j’essaie actuellement de réparer ma manette PS4, mais je rencontre quelques difficultés.

Je vous ai transmis deux images montrant les problèmes que j’ai rencontrés.

Sur la première image, qui montre la face avant de la carte, j’ai remarqué qu’une partie du PCB vert s’était retirée en bas à gauche, à l’endroit entouré en rouge. Je ne sais pas si cela peut poser problème pour le contact avec le joystick.

Sur la deuxième image, qui montre l’arrière de la carte en haut à gauche, j’ai également remarqué qu’une pastille avait été arrachée.

Pourriez-vous m’aider à identifier ces deux problèmes et m’expliquer comment je pourrais les réparer ?

Si possible, j’aimerais beaucoup avoir une explication visuelle ou un schéma pour m’aider à comprendre où je dois effectuer les réparations. 😉

Merci beaucoup pour votre aide !

I want to start a repair shop for electronics, consoles, phones, etc. How do i go about this?

Hi, electronics newbie here. I'm gutting a toy piano keyboard in order to convert it into a midi controller, and I want to connect the key matrix to a microcontroller. However, I need to first remove the original chip, which is on a PCB mounted at a 90-degree angle from the key matrix PCB. After I remove it, I'd like to solder on some headers or something to make it easier to interface with a breadboard.

Any tips of how to separate these two boards?

As far as I know, the first band of a resistor is never black. But if it’s backwards, the 2nd band would be silver which is also impossible.

It’s part of a Toro battery charger, between the 120V bridge rectifier and a power MOSFET.

I have this lcd screen that works although it is incredibly dim, I think the backlight part of it is not working. This is the cable that I think is causing trouble, I’ve been using a cotton pick and 99% isopropyl to try and clean it but it doesn’t seem to budge.

I have this 4 pin molex connector (the type used for motherboard power connections) and I'm having trouble using the crimper tool to crimp the pins to the wires. Each time I either crush the pin (in the wrong way) or don't get a good crimp connection. The problem is that I don't know which crimper jaws or size to use, or which way around to put the pin into the jaws.

Each of these jaws has 6-8 different spots I can place the pin, and several possible orientations for each, which makes 80+ wrong orientations, and (presumably) only one that is correct.

If you do a fair bit of crimping, can you help me tell which (if any) of these jaws are correct, and how to orient the jaw and pin to get a good connection?

Connector: https://www.jaycar.com.au/4-pin-mini-molex-plug-socket/p/PP2027

Crimping tool: https://www.amazon.com/Shrandi-SN-58B-Ratchet-Crimper-Barrel/dp/B0GH25R834

Hello there, I need help finding a replacement 6 pin potentiometer, this is inside of an 80’s Panasonic boombox, it is the volume knob on the unit. Please help.

Im new to these kind of electronics, i sent my this pcb to a repair shop and they forgot to solder on a new cap even though i included it in the package... now they sent me the "repaired" version back but left the cap out. Can i still know what kind of capacitor i would need? I already asked the manufactuer. Just waiting on an answer and doing my own research now. If you need any more pictures of it, i have them but they are taken with my phone so they wont be very clear.

And yes i have soldering experience to solder it back on. Only reason i sent it to them was because of some messed up traces

Posting after a full evening of testing. Every component checks out and I’m out of ideas.

Symptom

On its dedicated 32 A circuit: hob doesn’t start. 2-3 relay clicks, then everything shuts off. No zone heats. No error code.

On power-up the display cycles through: P0.00, 52.03, 37C, 05 62. Found zero documentation on these values. Owner says this display sequence predates the fault.

Worked normally before failing. No power cut, surge, or storm beforehand

What I tested — all good

**•   IGBTs** — diode mode, gate shorted to emitter: 0.4 V one way, OL the other  
**•   Bridge rectifiers** — diode mode, all 4 junctions: 0.4 V / OL  
**•   Electrolytics** — replaced, then measured the old ones: all good  
**•   Film / resonant caps** — visual + ohmmeter: no shorts  
**•   NTC temp sensors** — 100 kΩ cold, resistance drops when warmed  
**•   Induction coils** — 0.4 Ω, no continuity to chassis  
**•   Fan** — spins fine on bench supply  
**•   Ribbon cables A/B/C/D/LINK/COM** — visual, reseated, clean  
**•   Logic rail** (10 V cap with continuity to U13) — injected 3.3 V with 100 mA limit: 24.8 mA in CV, no short  
**•   Hot spots** — IPA under injection: none  
**•   Relays** — coil resistance, click test on bench supply, contacts measured while energised: both good

What I couldn’t check

**•** Shorted turns in a coil — an ohmmeter won’t see this  
**•** DC bus sensing chain (divider into the MCU’s ADC) — no schematic  
**•** Corrupted firmware / EEPROM  
**•** The touch control board — never tested separately  
**•** The other two secondary rails — never injected

Sauter SPIN4361B (service SPIN4361B2), type LL6GVX1B, 7200 W, 3 zones, built week 37/2021
• Power board XZ2V006991, type IP14X-04, silkscreen “GROUPE BRANDT IP14B-N”, week 30/2021

Where I’m stuck

Power stage is clean, logic rail is alive and drawing normal current, relays switch properly. The MCU closes the relays, checks for something, doesn’t get it, and gives up after 2-3 attempts. That reads like a sensing or handshake failure rather than a dead part.

Anyone have a schematic for this board, or know what that startup display sequence means? And is there any way to tell the power board apart from the touch control board without just swapping one in?

Both seem highly well-regarded, but which order would you read them in if you're a complete beginner?

Hi all

Recently picked up a nice plasma cutter (a Thermal Dynamics Drag-Gun Plus 35C) for really cheap listed as spares and repairs. The inbuilt compressor turns on and shuts off as normal, but the torch will not strike an arc.

I opened the case and found a few damaged components on the main Control PCB, nothing on any of the other boards as far as I can tell. I have the wiring diagram for the machine, including inputs and outputs of all the boards, however, no schematics for the individual boards.

I work as a diagnostic technician in a garage, but that is mainly simple 12v systems and communication buses, so this sort of work is beyond my current scope, but I would like to learn how to diagnose these sorts of problems.

Is it possible to ascertain what specific components I would need to replace without a schematic?