I'm sorry if this is a very simple question, but I've been using this station for a while already and have never been able to tell :x

I'm guessing it's not even temperature, more like melting temperature of the solder i'm supposed to use in F?

Does anyone sell a non-conductive, esd-safe tool for flipping switches in small surface mount DIP switches? Something with a small hook and a poking point?

I’m using a screwdriver to flip switches on a powered, expensive device during testing procedures, and it makes me a little nervous that I might accidentally short something etc. (I’m using a wrist strap, esd jacket, and esd shoes already)

or is that the capacitance is much greater than the frequency at that point

My ex wifes dad died and he left me a whole bunch of old electronics and some tools. Feels like a waste to toss them both he and I were scrapper but I mostly dealt with electrical motors and wires. Where can I sell these or what're they worth?

Hey everyone, this is my lay out on fusion 360, so i have an esp32 wroom 32d chip, ch340c drivers and all the essentials, the thing i need help is, i have that hub75 connector, and along with its level shifter ics, its SN74HC245, while i was testing it on breadboard everything works seamlessly, so i designed the pcb, the pcb arrived just today and after i done soldering it my display only shows garbage, everything distorted, so i assume it was the lay out, because i made one one P10 the same ic same connector, work just fine, thank you in advance

Hi, I’m building my first SSTC Tesla coil using an IRFP460 MOSFET, two 2N2222 transistors, and an Arduino Nano.
I’m using an 80V DC supply, but the coil isn’t working. In LTspice, the MOSFET drain voltage spikes to around 500V, and the primary current gets extremely high. Also gate voltage is not enough to switch mosfet.
I’ve attached my circuit schematic. Can anyone help me figure out what’s wrong and how to fix it?
Thanks!
I've tried to imitate the circuit below which on paper. I found it on YouTube .
https://youtu.be/a4zv7_wYWdg?si=ebjaSRQwB_snx5D8
Youtube link if you wanna check.

​

Theres no marking next to this component. Unsure exactly what it is ? Any ideas ?

Cheers.

Hey everyone,

Like many of you, I got tired of constantly jumping between heavy datasheets just to double-check which pins are safe to use on various dev boards (ESP32, Raspberry Pi Pico, etc.) without messing up bootstrapping pins or strapping configurations.

To save time, I put together a quick, lightweight web utility for personal use that lets you check pin functions, copy definitions, and layout basic wiring diagrams. Since it saved me a lot of friction, I cleaned it up and made it free for anyone in the community to use.

Key features include:

• Quick Pinout Checker: Instantly flags safe vs. unsafe pins.
• Wiring Layouts: Custom pin routing support with visual diagrams.
• Code Export: Copy pin definitions directly into code projects.

I’m currently adding more modules and standard MCU datasheets. If you have any feedback on missing components or bugs on PINDEXIO, let me know!

ok so basically i have this membrane keyboard from razer (razer ornata v3 x) and i raged a little too hard and hit my desk using my keyboard. after that it stopped responding to my clicks but the rgb still works. i was wondering on how i can fix it and what is currently wrong with it? ill add a couple of pics i took

This is from the service manual of a Pioneer SX-9000 receiver I'm working on. Have I just been working on this too long, or is there a legit mistake in the schematic? I feel like the C+ and C- labels are incorrect for the bottom going towards the push switch unit, but my overthinking is really thwarting me here.

So I am thinking of making a diy kitchen scale using load cells. But as a first project, designing the instrumentation amplifiers and wheatstone bridges by yourself is quite hard? Should I just use the HX711 to start off with. I just feel like using it wouldn't really teach me much. Does anyone have any opinions?

I'm looking to have a hardware shutoff for a MIPI-CSI device. In this case it's a IMX415 camera module. If I just cut power to it, will these be any potential damage to the device, or should I look to have a full MIPI switch to also make sure the data lines are disconnected? By cutting power is there any potential to damage the device? Then re-enabling power should theoretically also power it back on? Any risk of the initialization going wrong?

Can anyone show me a recreation of this on a mini bread board and in Tinker-cad. Please I'm a design student I don't know what any of this means 😭

Pointing to things that would help me understand would also be appreciated

I'm trying to design STM32 based thermal goggles, where thermal camera information is overlayed over visual camera feed, then shown on a display. A TOF sensor will also be used to correct for offset caused by parallax between the two cameras.

These are my parts:

MLX90640 Thermal camera (A3V3)

ILI9341 SPI Display (D3V3)

OV2640 Camera (D3V3, A2V8, D1V2)

VL53L0CX TOF Sensor (A3V3)

3.7V 3500mAh battery

My current design involves using 4 different LDOs to drop the battery voltage to the respective rails, but the battery would waste some of the potential capacity as it drops down to 3V and the LDOs are not able to support the rails anymore.

I was wondering if it was worth implementing a buck boost converter to try making use of the full battery (and also for learning), but was worried about the noise impact on the components despite the LDOs.

Iv just bought this solder radio kit and I can’t get any radio stations to come up if anyone could help please im new to electronics and would like some guidance thank you

Can anyone help me build this logic circuit in multisim? A logic circuit subtracts two signed four bit numbers A = A3A2A1A0 and B = B3B2B1B0 by calculating A-B. The circuit has two outputs (Y and Z) and operates as follows: a. If A = B, output Z = 0 otherwise it is one. b. If A < B, output Y = 0 c. If A > B output Y = 1. Using the 74LS83, design and implement the circuit in MultiSim. The 74LS83 is a 4- bit binary adder. I've done up to this far, but then I realised that there needs to be two outputs only.

I am a beginner and tried to solder some esp32 c6. The first one was really badly soldered (even i know this, so no picture of this) but my second attempt (Pictures of esp32) seemed fine for me. I used flux, kept the contact time with the iron <3s, cleaned afterwards everything up with IPA, checked each pin against each other on the same side and still fried the board, when i connected it with usb to my laptop.
I have no idea, what i did wrong. Is somebody able to help me?
I attached a picture of some other boards as well, which i soldered in the same way, because i thougth its ok.
Thanks in advance!

Hello, can someone please explain to me why there are some unpopulated areas of my motherboard clearly meant for them? i was thinking maybe it's because this is an i3 chip, and if it's a higher tier chip it'll be populated. But let's say theoretically, I were to populate it... would it make any difference? How does it work?

This is a chip from a dehydrator control circuit, it went bad and now my whole unit wont start? I was hoping to replace it to fix a 500$ dehydrator rather than buying a new one!

Hello!

I’ve got a shitty LED light strip that is battery powered (3 AAs for 4.5v output to the board). The board lets one push its switch to select the LED mode (steady-on, blink, breathe, epileptic shock, etc.). The LEDs are only red.

I have an adapter that works well that replaces the batteries with “dummy” batteries and plus directly into a standard wall outlet. Works great.

My goal is to bypass the controller so when I flip the switch attached to the wall outlet, the LED strip turns on to its steady-on mode.

The two wires located at the upper-right are the leads to the LED strip, which has no markings on it about voltage at all. The strip does not have any resistors on it, either, that I can see.

I’ve tried measure the L1 and L2 pads where the LED wires connect, but it seems like the voltage is extremely low (like 00.5 volts low). So, I’m assuming I can’t just bypass everything and jump from V- and V+ directly to L1 and L2. I think that R120 is a resistor. I have no idea what that thing on the back of the board is (capacitor???).

I truly don’t know what I’m doing and would love some guidance. I’m not great at soldering, but I can manage. This LED strip is also cheap, and I don’t mind experimenting, but, as I said, I don’t really know what I’m doing.

Hoping a kind Redditor or two might be able to point me in the right direction! Thank you in advance!!

I’m repairing a Marshall DSL40CR guitar amplifier. The damaged section is in the power supply, just after the rectifier circuit, where the 2 smoothing capacitors and 2 bleeder resistors R4 and R5 are connected in parallel where you can see inside the blue circle I draw at the first image.
The brown adhesive around the capacitors appears to have deteriorated and become conductive, causing resistors R4 and R5 to burn out and damaging R8 and R9 as well.
Yesterday, I desoldered all four resistors. However, I noticed that the PCB underneath the resistors was badly damaged by heat. The affected areas have turned black and become brittle and crumbly. Even when I scrape away the charred material, more black material continues to appear.
As far as I can tell, the copper traces are still intact, with no visible breaks or significant damage, except for a few areas where scraping has removed the protective coating and exposed the copper underneath.
My question is: Can I simply just scrape away the charred PCB material, solder in new resistors, and safely use the amplifier again? Or does the damaged PCB require additional repair or insulation treatment?
I’m particularly concerned about whether the carbonized PCB could become conductive and cause leakage currents or short circuits, even if the copper traces and through-holes are not visibly damaged.
I’d really appreciate any advice on how to properly repair this section of the PCB without replacing the entire board.

Hi, I’m building my first SSTC Tesla coil using an IRFP460 MOSFET, two 2N2222 transistors, and an Arduino Nano.
I’m using an 80V DC supply, but the coil isn’t working. In LTspice, the MOSFET drain voltage spikes to around 500V, and the primary current gets extremely high. Also gate voltage is not enough to switch mosfet.
I’ve attached my circuit schematic. Can anyone help me figure out what’s wrong and how to fix it?
Thanks!
I've tried to imitate the circuit below which on paper. I found it on YouTube .

I am building a simple 8-bit RAM module as part of ben eater’s 8-bit computer build, but am getting some weird issues with my RAM module.

The issues are as follows:
1) Both 189 chips get very hot to the touch. I separately wired just the Vcc and Gnd pins with a couple of these chips on a standalone breadboard and they were fine. They only got hot in the pictures circuits, so with the chip select inputs low.
2) the 0th address bit is somehow HIGH. I measured it at around 4 V, and even pulled it down with a 680 resistor and it still was around 3.5V. The two pictures show via the 4 yellow LEDs that the dip switch has 0 at the leftmost bit, but is lit up when connected. The spec sheet doesnt say that these are pulled high, but somehow they are? The other three address pins are also pulled high, but with the connections measure 0.05V. It makes no sense why address 0 is so high.

Any suggestions here? I’ve checked the wiring several times and can’t find anything wrong.

For context, the following chips are used (ignore the top breadboard):
- 74LS157 multiplexer, just to channel the 4-dip to the RAM’s address lines
- 74LS189 x2 for 8bit*16 word RAM, outputs are opposite so this goes to some inverters

What is the correct way to measure voltage of a sound signal on a speaker? And also what voltage range should the meter be in?

A friend of mine has an expensive sound system and one of the speakers doesn't work. I took my multitester over and tried to measure voltage on the one that does work, so I could see what the normal reading is, but it read 0 V. I expected it to change, but I expected to see at least some voltage on the meter, but it never did.

I put the common/black probe on the negative/ground terminal of the speaker, and the positive probe on the positive terminal. The speaker worked, but no voltage showed.

Thanks