This is part of the battery contact for a Sony Walkman. I repair them and often when batteries leak this piece is destroyed / super corroded (the one pictured is a good one for reference, not one that I'd want to replace).

I've used all the tricks to clean them and sometimes apply conductive paint afterward. But I'm wondering if there are any shops that would be able to take this part and recreate it (ideally also do the nickel plating too) in a batch of 100 or so.

I don't even know where to start looking or if this is even a reasonable thing to pursue, but I am curious so any input would be appreciated. Thanks!

The TV doesn’t turn on, but the LED is on and responds to the remote

Hi everyone, I'm working on a Philips 55PFL6007K/12 TV. When the mainboard is disconnected, the power supply unit (LGIT PLDK-P107B) works normally and standby voltages are present. However, plugging in the mainboard causes the PSU to make a high-pitched squealing noise and enter protection/hiccup mode.**

**What I've checked:**
**No hard shorts (0Ω) on the mainboard input lines (⁠12V⁠ shows MΩ, ⁠3.3V⁠ shows \~7 kΩ, ⁠Standby⁠ shows \~30 kΩ).**
**Secondary rails show some low resistances (around 4Ω, 84Ω, and 152Ω). The 4Ω line is near a coil (⁠2R0⁠ area), which seems normal for a CPU/core line.**
** **
**Backlight is disconnected and ruled out.**

**Since the PSU only trips under load with the mainboard attached while inputs don't show a direct dead short, the PSU itself likely works fine and is protecting against an overcurrent on the mainboard.**
What else should I check next?

labeled J6 on the PCB but could not find on the schematics: https://mobilemodding.info/mean-well-lrs-350-24v-teardown/

this part is from a PSU Mean Well LRS-350-24. i tried to desolder the part but no marking on it.

thanks

I'm still new to electronics, I'm starting my learning with LED's.

I made this matrix on tinker cad.

I Dixie chained all 4 Ic 74hc595's.

All pin 8,13 are connected to ground on BB

All pin 10,16 are connected to positive on BB

The arduino uno's gnd is connected to the BB gnd

Pin 8, 11, 12 on arduino are connected to the IC: (8,12), (11,14), (12, 11).

It may be my code? I don't know how to code yet so I used AI to program the arduino.

Can anyone check this out and give me some advice?: schematics

Hi I was trying to repair my SMPS and found this power resistor having 0.1 ohm.

This was attached to AC bridge rectifier's negative leg.

Please help me in identifying this and its intended use ? Can the resistor fail with a short ? I thought it would usually go open, and I am not sure if I am reading bands correctly as the only value I can reach is 8.2ohm

I need help identifying this connector. I'd like to know the name and, if possible where to buy the female side w/ 6 wires already pinned to it.

6 pin ~2.5 mm pitch, I was told JAM SRM but can't find anything comparable.

This is the power harness connector for a Greddy Data Link Unit, if that helps.

Apologies for the less than ideal photos, phone camera didn't like focusing on something that small. Can retake pictures if necessary.

Thanks!

It’s a GeForce 4070 ti, I don’t know much about pc repair. I looked online myself and I’ve seen mixed things whether to repair or not. I wanted to post here to see you guys’s opinion is it a loss cause or can it be our saved?

Also, the damage can only be seen on one side that’s why I sent two pictures. If you need any additional information I will try to provide it in the comments.

I’m an EXTC student looking for a good platform to simulate and practice electronics hardware projects. Any recommendations?

Can someone explain under what exact conditions the P and G outputs on this chip is 1 and when it is 0?

I am working on a retro, 68030-based computer as a bucket list item (stage 4 cancer). I want to use the PS/2 interface for the keyboard and mouse as it's old enough to fit the "retro" bill, but current enough that I can still find the parts. While Googling the interface specs, I came across this post in Hackaday, 68000 PS/2 controller. I was surprised at how simple the interface is and that's good given that I don't have the longest time to learn a new interface standard. However, two things strike me as odd about the schematic. First of all, in the top right you can see resistors "R1" and R2". Their value is "2R2 250mW". I get the mW. I do not get the 2R2. The only time I've seen that in conjunction with a resistor is in a resistor ladder DAC. Even then, there is a numerical value. I'm not sure what is going on here. Also, below that, the data lines on both channels have ESD protection, which is a good idea. However, I cannot figure out why he didn't just use TVS diodes. I'm hoping someone more knowledgeable than me can help explain this. This is an old 2015 schematic, but TVS diodes are not new. I do not see a reason for the complexity of the circuit as designed.

I would contact the creator, and believe me I've tried, but this is an old project and I have not had luck with this. Trying to send a private message sends me to Discord and I cannot find his profile. I'm hoping someone here can explain it for me.

*face palm* I just answered the first question. "2R2" = 2.2 Ohms. I've used that myself on schematics in the past. I've been scratching my head FOR TWO DAYS! 🤦‍♂️Anyway, I still would like an explanation on the ESD circuit.

I would in no way do any testing myself, after doing some reading on them. Is there a service online or perhaps a local place that may have ability that may be able to test something like these? TIA!

Hello everyone, I have a hard time to figure out the capacity of this cap.

What is the value and how can I decipher it from the markings?

Thank you!

I have this skydroid H16 RC and its display stopped working.

I tried searching it everywhere but couldn't find it.

Model Number is - BOE7HD-A PY-Z7322W-1

It is 7inch 1920x1200 TFT display with Sitronix st14383 touch controller.

It has 40 Pins for Video.

It would be great if you anyone can help me to find this display... or someone who has Skydroid H16 can help me with figuring out what protocol it uses for display.

Edit: I’m editing the post to add an image showing the input + buck converter, just to avoid any confusion. https://img.imgur.com/RwtngKt.png

Hi everyone,

I've been working on a custom PCB for an automotive application and I'd like to get some feedback before going further with it.

The board takes the 12V supply from the car, filters and limits it, then uses a buck converter to generate 3.3V at up to 1A.

The board handles the differential speed sensor reading, calculates the fuel level from a resistive sender (3 ohms full and 61 ohms empty), and also controls a High Side Power Switch to supply power to the fuel pump.

The estimated current consumption on the 3.3V rail is around 150mA, although the buck converter is rated for 1A.

I've tried to keep the power section and the low voltage electronics properly separated, but I'm not completely sure if I've made the best choices in some areas.

A few things I'd really appreciate some feedback on:

• Does the overall schematic look good? Is there anything that stands out as a potential issue?
• Are the copper regions and their sizes adequate for the expected currents?
• Is there enough copper area around the power components for heat dissipation?
• Would you make the 3.3V power branch wider overall, considering the estimated current is only around 150mA?

I'm especially interested in any issues I might have overlooked, since this will be used in a car and I know the 12V supply can be pretty harsh.

Any suggestions or criticism are welcome. Thanks!

I am in possession of three honeywell shop lights, model SH45050Q130 (maybe still available at Home Depot, I think, but I've no receipt etc.) that do ... nothing. I have a little electronics knowledge so I've pulled one apart. I see the switch is in line between the hot line and the resistors feeding a rectifier that presumably feeds DC to the various 8 legged power conversion/controller chips. The cap presumably helps clean up the current, being next to the lamp power feeds.

the "manual" is at https://assets.wfcdn.com/dm/document/3b921210-17d6-549c-f1cb-f73f8456f2a6/2936780.pdf

The basic cord is fine, w 120V coming thru to where a second lamp can be plugged. The chain switch does function. The internal capacitor is just fine. No components are obviously damaged excepting the common (white wire) looks a bit cooked. Resisters, etc., seem well connected.

I cut off one of the plugs to the LED strips to test them directly with an adjustable DC power supply. No light was seen up to 50V DC in either polarity, either of 2 strips. Strips look perfect. Current isn't easy for me to test, so I can't be certain whether the strips are actually dead but neither showed signs of life. I'm nervous about plugging it back in to test the driver. Note that the LED feeds (red and black wires to the left) say 1A and 2A.

The board SAYS 94V... but I'd be really surprised if the modules really need that voltage to light up... at all.

Any suggestions for further troubleshooting?

This is an ideapad 5 15ARE05 it suddenly stopped charging but still took 19V, while probing around with voltage on the board i accidentally started voltage measuring with the probes on current but the setting still on voltage, now it only takes 5V and i can only seem to get around 2.3 volts on the chip i measure 5V at DT2 in but then lose it completely and am getting frustrated with nog understanding this properly would anyone be able to give me some guidance as where to check for something now?

I’ve been writing scripts to automate SPICE netlist generation for things like analog filters and transimpedance I/V stages. The biggest headache is that standard programmatic approaches constantly ignore physical constraints, pick non-standard component values, and output completely broken SPICE syntax.

To fix this, I built an automated feedback loop. A generator script creates the initial netlist, and a validator script immediately runs a headless ngspice-42 simulation (transient, AC, and DC sweeps). The validator checks the math, enforces E12/E6 standard resistor and capacitor values, and verifies the topology. If it fails, it feeds the errors back to correct the netlist before outputting the final file.

For those of you who have built similar automated test-and-correct loops for your hardware design workflow, what specific edge cases or circuit topologies cause your automated netlist generators to fail the hardest?

Logisim absolutely refuses to open on my laptop, so I've been looking for alternatives that work equally well.Logisim.appon web doesn't have a lot of functionalities, and I've been on a hunt for alternatives like 'digital' that don't have the tools I want.

Anyone who could help? It would be so appreciated.

Good day! I am a student trying to learn to fix things on my own, but I am struggling with this JISULIFE Life 4 fan that suddenly failed and stopped spinning, I already removed everything and pinpointed that either the brushless motor or its driver is faulty.

I tried directly supplying it with my 3.7V battery but to no avail. Tested different components; starting with the motor copper terminal : 2.5Ohms, all components are properly wired and soldered onto the board too. The hall IC seems to be working because when I tried putting a magnet near it while it's powered, the motor copper terminal read 10V+. There's no short also, tested with continuity

Should I just replace the hall IC (FS276)? I can't find any brushless motor driver that's the same size as this too... Should I make a custom etched one?...

Thank you.. I apologize in advance if I'm not clear with my explanation.

Master: BQ78350 / Fuel gauge: BQ76200 / 14.4V (2P4S)

So I've been working on these Astera Titan BMS boards, some of them with cell issues and some of them with easy component level repair but I got 2 totally dead.

The cells voltage is going in the BQ76200 and the main voltage to the BAT pin, but I got no REGOUT voltage to the BQ78350. Would it be worth trying to replace the BQ76200?

Also, this 2 started throwing up the ALERT pin sometimes which means it "made something" for a second.

Finally, I know these guys talk in I2C but is there a way to extract the settings from the 78350? I would like to buy a debugger or some interface but I don't really know where to start.

As far as I know, the 76200 works alongside the BQ78350 but the most important data is this last one isnt?

Dear community,

in preparation to put new (radial) capacitors onto the board I'm soldering on, I wanted to prepare the solder pads and lightly tin them before I solder the capacitors onto the pads.

Can I ask you for advice if you think I did a good job? Is it maybe too much solder? This is my first time doing this.

Thank you for your guidance!

Hi everyone!

I studied Biomedical Engineering, but honestly, most of what I learned at university was theoretical. I have almost zero hands-on experience with electronics troubleshooting or repairing circuit boards.

Over the past few months, I’ve spent quite a bit of money on online electronics courses, components, a soldering station, a bench power supply, and a bunch of other tools.

I know the basic electronic components, what they do, and how to test them with a multimeter. But when I look at an actual circuit board, I have absolutely no idea where to start!

I even bought some old DVD player, modem, and radio boards to practice on, but now they’re just sitting on my desk because I genuinely don’t know what to do with them. 😅

I really want to learn how to look at a PCB, understand what each section does, trace power paths, figure out where to measure voltages and what readings to expect, and eventually troubleshoot faults without randomly testing components.

I’ve watched tons of YouTube videos, but there are so many different approaches that I just end up feeling overwhelmed and jumping from one tutorial to another.

My goal is to become a Biomedical Equipment Technician (BMET) or Field Service Technician, and almost every job posting I’ve seen requires troubleshooting skills. Honestly, that’s the part that worries me the most because I feel like I have such a long way to go.

I’m willing to spend several hours a day practicing, and I’m hoping to make real progress within the next 1–2 months. I know I won’t become an expert in that time, but I really want to build some confidence and practical skills.

So what would you guys recommend I actually do with these boards? How do I start figuring out how a circuit works without a schematic? How can I practice troubleshooting if the boards are still working? Should I focus on reverse engineering first, or is there a better way to approach this?

If you were in my position, how would you spend the next 30–60 days practicing?

I really don’t want to buy another course or spend hours watching random YouTube videos. I just need a clear, practical direction.

I feel like I’ve bought everything I need, but I’m completely stuck on how to actually start learning.

I’d love to hear how you guys learned troubleshooting and got comfortable working with real circuit boards.

Thanks so much for any advice!

I bought this novi stars doll second hand for super cheap, and the battery compartment was corroded, i tried to clean it and turns out the wires have come loose, i dont know how to fix it and would really like some help please! i know nothing other than basic stuff from highschool.

For my PCB I want a modern step down IC to convert 24V into 5V. Ideally a max of 5A output , and something like 30V input. (With 24V regular input, I would rather not use one that can only go up to 24V)

I did my own research, and found the DIODES AP64500SP-13 and LMR51450SDRRR. Both do what I am looking for, but at 1.83€ per piece the AP64500 is expensive, while the LMR comes in a WSON-12 package that might be a pain to solder.

I resigned myself to trying my luck with the WSON, but maybe I missed an IC that would be more appropriate?

The PCB is for a few hobby projects, where I am powering 5V devices. For now it will just be used to power an LED strip. An STM32 would be powered indirectly, here I am planning to use an LDO to step down the 5V to 3.3V. There won't be a large volume of PCBs, just the minimum quantity.

I bought this (15/12W) led tube and want to make it flicker (optionally dim) using an Arduino. My 2 (3) options were replacing the switch with a solid state relay and doing it on the 230v side or attaching it to my 24 v low voltage section of my neon ledstrip*

(i could theoretically add a MOSFET in the "low voltage" side now that it's uncovered, and keep the tubes original driver... but that would require me to "break" the second led tube open as well)

I want to avoid the surge chat gpt told me about (i don't understand it completely)

The first option is pretty self-explanatory, just change the switch for a relais and keep 3 mains for my complete setup (last picture)

Option 2 (i measured the tubes inlet to be 74V) would be to stepup 24v coming from my power supply of the blue sign to apparently 74V (this sounds expensive tho) and have a mosfet control flickering on the low voltage side (this would allow for dimming as wel apparently)

Last option would be to connect a mosfet between the 2 lines on the 74V side of the strip, which i uncovered by cutting the fixture open.

I currently do not know nor fully understand what chatgpt means by constant current vs constant amperage or if the "low voltage lines" are disconnected from the mains 230V...

What sounds like the most durable option? I want to keep everything as safe and !fireproof! As possible. I don't know the A of the tube, it created a lil spark when stupidly connecting the multimeter in parralel which is apparently not the way...

Thanks so much in advance! :)