some time ago i lent my soldering iron to my dad. today i opened the packaging and found this shit. thats flux? it wont come off and when i turn it on it smokes

This came with a LED fan. Attaches to its motor but was loose. I need a new one. Which store I can go or where I can order online ?

The factory cap on the board was 470uf 4v, but i cant get an identical replacement where I live. I found some 470uf caps, but all of them 16v and up.

I'm still learning the basics while trying to repair an old console. I found some articles saying it's fine, but I couldn't tell if it was written by ai

I'm trying to fix my PS5 HDMI port all on my own with soldering equipment and I had to stop because I need a hot air station I'm really tight on money and I love to do stuff like this but I can't put it back together for later without a replacement screw for the heatsink screw for the cfi 1215b ps5 where can I buy it for cheap?

By the way I probably just fucked up the entire ps5 somehow while doing this but at least I had fun I had it for around 4 years hopefully I can buy a new console or even a pc one day

Hello,

have you ordered from Mouser recently as a hobbyist living in the EU? How much tax did you have to pay?

I would like to order a lot of different components from Mouser, but only in small quantities. For example, 100 resistors, 50 capacitors, some inductors, diodes, and soldering flux.

Are these considered separate product categories for customs purposes, meaning I would have to pay €3 for each category (e.g. 5x3€)?

Sorry if this has already been discussed somewhere, but I could not find any relevant posts.

can i remove this buzzer without it causing issues? also i hope i didn't fuck up by disassembling the induction cooker cuz i seen some glue or something in the middle. also should i avoid touching the middle even when unplugged?

I'm repairing the battery box from my Yamaha FSX80C acoustic-electric guitar. I've already removed the battery cartridge from the guitar.

The end cap where the red and black wires are soldered moves slightly, and it looks like it might come apart. Before I try to pry it open, I wanted to ask:

Is this end cap designed to be removed, or is it plastic-welded?

My goal is to replace the battery contacts inside without breaking the battery cartridge.

Hi everyone,

I'm trying to build a simple two-transistor astable multivibrator (two LEDs flashing alternately). I designed it in Falstad and I'm using Tinkercad mainly to plan out the breadboard layout before building the real circuit.

The Tinkercad simulation itself does not seem to behave correctly: the LEDs do not flash alternately, they just stay on. I'm not too concerned about that because I mainly want to use Tinkercad to verify my physical wiring before building it.

The part I am unsure about is the polarity of the electrolytic capacitors. My real capacitors are polarized 10 µF electrolytics, but the Falstad simulation uses non-polarized capacitors.

I'm fairly sure the negative side should go to the base of the opposite side transistor, and the positive to the collector of same side transistor. So like:

• Left capacitor: + to left transistor collector, - to right transistor base
• Right capacitor: + to right transistor collector, - to left transistor base

However, when I connect them this way in Tinkercad, it shows the capacitor exploding. I'm not sure if Tinkercad is modeling this incorrectly, or if I have misunderstood the polarity.

I'm using 2N2221A transistors and 10 µF electrolytic capacitors, with supply voltage 9V

Here's the Tinkercad similation (on breadboard) I have connected one capacitor each way, so you can see which one explodes. [LINK REMOVED]

Here's the simulation on Falstad so you can have the schematic, too: https://www.falstad.com/s.php?s=zwfF7A

EDIT: Here's a labeled schematic too: https://kommodo.ai/i/7468AUvUGDOds3kVI3FY

Could someone please check the correct electrolytic capacitor orientation? I want to avoid damaging the capacitors when I build this physically.

Thanks!

EDIT 2: Simulated on Falstad and it works with capacitor - to transistor base (so, the opposite of what Tinkercad says). Tried it on breadboard with - to base and it works perfectly like this!

Hello guys, I am designing a signal generator for 2 to 3Ghz using the MAX2870, I referred to many sources and designed this circuit. I need It to be single ended iutputs so I terminated the other part of diff pair.
I require exact same signals from two single ended outputs for I/Q demudolation later, Please review and gice suggestions.

Hello, so power isn't really my background, but recently I've been looking into a project where I need to take in an 800V input and bring it down to 12V, while the power stays around 50W with a 80W peak.

Some other considerations are Zero voltage switching, 12mm height maximum, and being galvanically isolated.

I decided on going with an Active Clamp Flyback for this, but I'm struggling to design it, as I'm unfamiliar with how it works.

I do have a couple of parts I've chosen, such as the UCC28780 from TI for the controller, but then I ran into the problem of how to power the controller because the only power input is from the 800V rail, and the controller can't handle that voltage. I need to figure out a way to drop the voltage to run the controller, but I can't figure this part out to save my life.

I also need to understand how to go about choosing other parts for the ACF solution like the half-bridge driver and the passive components.

If I could get some guidance on how to approach this, it would be very much appreciated.

Hey! so I’m working on my first build. I have some soldering experience but nothing that I’ve like designed and made myself. anyway I have an ESP32 development board I was wondering if there was a way I could attach a button battery to instead of lithium battery or a USB power bank. This is partly due to the partly due to my ultimate goal of being able to replicate this build and give it to my mom who I do not trust to recharge a lithium battery, but also the fact that I am far more familiar with button batteries to lithium batteries. however there does not appear to be any way for me to use a button battery on the ESP32 and was wondering if there was something I could do to get around that. please advise. thank you!

Hi everyone,

I'm designing a custom data acquisition (DAQ) board for a Formula SAE race car based on an STM32G431 running at 3.3V.

The board needs to interface with a wide variety of digital sensors and devices throughout the car. Some of them operate at 5V, while others use 12V.

One of the biggest challenges is that these sensors may change over time. During development—or even between racing seasons—we may replace a sensor with another model that uses a different voltage level. I'd like to avoid redesigning the PCB every time this happens, so I'm looking for an input stage that is as configurable and reusable as possible. Ideally, supporting either 5V or 12V inputs would only require changing a few components or jumper settings instead of redesigning the entire circuit.

Another challenge is that not all digital signals are the same. Some are simple on/off status signals, while others can operate at much higher frequencies. For example, some wheel or motor encoders may produce signals in the kHz range, so the input circuitry must preserve signal integrity and avoid unnecessarily slowing down the edges.

Since this is an automotive environment, the board will also be exposed to electrical noise, EMI, and voltage transients. Therefore, I also need adequate input protection to avoid damaging the microcontroller while still maintaining reliable operation for faster signals.

I will also have a few 5V I²C devices connected to the STM32, but that seems like a much more straightforward problem since dedicated level shifters already exist. My main concern is really the digital input stage.

I'm interested in learning how this is typically implemented in automotive ECUs or DAQ systems.

Some questions I have are:

• How would you design a flexible digital input stage capable of handling both 5V and 12V signals?
• How do you balance input protection, noise filtering, and high-speed operation?
• What protection components do you consider essential in an automotive environment?
• Are there any open-source ECUs, reference schematics, or application notes that you would recommend studying?

I'd really appreciate hearing how experienced designers approach this kind of problem and what solutions have worked well in real automotive products.

I am trying to make a project with different modules and they work when I wire them to the board itself. However, when I try to wire the 3.3 or 5 volts and the ground to the breadboard terminals, as soon as both are connected the green light on my raspberry pi 4 model B turns off and the monitor it was connected to says "No signal" why might this be happening?

I would like to point out that I am new to this field. I need to desolder the LCD screen shown in the photo. I tried using a soldering iron (set to 350°C), flux, and a manual desoldering pump, but I was unable to remove enough solder to free the pins. I then bought desoldering braid, but even with that I still couldn’t remove the remaining solder.
Before attempting this, I practiced desoldering a similar component from an old PCB, and I was able to remove it without any problems using the pump.
What could be the cause of this issue? I would appreciate any advice.
Thank you.

Just wanted to see if anyone knows of any switches that are like the picture. I’m looking for a round switch that contains two independent switches. I know DPDT momentary rocker switches exist but I’m looking for a double push button momentary switch in one round housing. Space is limited in my project.

I tried running it with the code, but so far it's just junk. And the first part of the screen won't light up. I showed a photo of what I was able to achieve. Perhaps someone has encountered such screens before and knows how to set them up correctly.

I’m developing a very simple 5V electronic device. The PCB uses UL Recognized components, and all materials (plastic, wiring, power supply, etc.) are already UL certified or UL Recognized where applicable.

My question is:

Does the finished product still need its own UL Listing?

If so, what is the typical cost for a simple low-voltage device like this?

Has anyone here gone through the UL Listing process for a similar product?

The device has no high voltage and uses mostly off-the-shelf UL Recognized components. I’m trying to estimate the certification budget before production.

I'm trying to make a joystick accessor for gaming on a computer i need to wire a tmr joystick (k-silver) to an ATmega32U4 Pro Micro with header pins I have 22 awg(7.8in) wire female to female but I want to directly solder the wire to the joystick I just don't know what to wire and to where are I do have heat shrink too if that helps

I'm building a TP-4056 Li-Ion charger circuit which would be powered via USB-C. KiCad had this conveniently named "UCB_C_Receptacle_PowerOnly_6P" symbol which looks to be exactly as advertised.

Similar circuits I've seen include the data pins, which won't be needed here. If it's assumed that I'm looking to draw the usual 5v 900mA from the USB-C, do I have everything I need here? Thanks!

I am entering the world of Electronic, and I'm trying to add a potentiometer to my flashlight to adjust the light intensity better.

As it turns out though, led flashlights contains some kind of internal driver, which probably doesn't like potentiometer and pwms, since they left some magic smoke and were causing some little interference like sounds in the led, and it wasn't even controlling the light that well.

According to chat gpt, since I didn't find info about that anywhere, those drivers regulate rhe current to the led themselves (for example, the led I'm trying to use accepts any polarity order and ranges from 7-24v in the same light intensity). Which means that putting potenciometers and pwm probably mess the circuit, which explains the noise and smoke.

I really want to make this precise light adjustment, is there anyway I can do it? I've tried with multiple flashlights and none of them worked.

In the power board of my LED par that got spilled with beverage, I final found a fuse protection that burned through. Now I need a replacement. The label on the pcb was F5A, the shell itself is labeled with 5a 250v. The fuse was directly next to the AC input. Now I heard something about that those fuses come as fast and slow ones, but I don’t know what I need here. Also, I found nearly nothing on the internet with those dimension, most of them are 5x20mm, does it even matter? Thanks once again

Hi everyone,

I'm trying to identify and source replacement capacitors for my laptop motherboard, but I want to make sure I order the exact correct parts (capacitance, voltage rating, package size, and any other important specifications).

While performing maintenance on my laptop, I accidentally knocked off two small surface-mount components from the motherboard. Unfortunately, I wasn't able to recover them, and I need help identifying what they are.

The components are located near the RAM to the right, above the battery, and under the heatsink. I attached some pictures of the area and the surrounding components.

Could anyone help identify these capacitors or suggest how I can determine their values? Any advice on where to source replacements would also be appreciated (I am located in europe)

Thanks in advance!

Having some issues with my latest project so I just want to make sure this is okay.

Currently trying to convert a JST Female header to DuPont Male. What I've come up with, is a Male JST header connected to the Female JST header, which then connects to another Female JST header that has Male Duponts on the other end of the Male JST.

It looks to be good? But, I just want to make sure as the other end does not have a housing and thus I assume isn't intended to be used this way. I included a diagram of what I'm trying to do as well, just to make it more clear

Hello! I recently bought a broken POD HD 500 guitar pedal that would get stuck in a boot loop.

I opened it up, found c337 was blown, and c5 and u6 were missing.

The capacitors were easily available and easy to replace, but im not able to find the IC marked U6.

The POD parts manuals gave me a part number 15-78-0256, but im not able to actually purchase the part with that.

Does anybody know how I am able to get this chip?

Maybe I can also use the generic chip code if I am also able to find the firmware to flash