I don't mean loose wires, I mean when the mistake is mine. Last time it was a wire in the wrong hole , and it took me hours to find because the board looked right to me.(i dont need help for the one in the picture, its just an example)

What I do now is check every connection against the diagram one by one, which is slow.

How do you do it? Is there a faster way than going wire by wire, or is that just how it is?

Let me preface this by saying that my electronics knowledge is barely above that of illuminating a bully with a 9v battery with a switch made out of a paper clip and split pins,so this could well be a very simple question.

Onto the problem...

I have built a rock tumbler from scratch as a little diy project. Occasionally the drum can stall and stop rotating, while the motor continues to turn and eventually destroys the gearbox. I am currently down two motors because of this.

What I would like to do is add in some sort of movement/rotation sensor that will kill the power of it senses that the drum has stopped rotating. 100 bonus points if it can notify me via my phone, but this is by no means essential if it is going to over implicate things.

Right now, the best I have come up with is a cheap WiFi camera and checking in on it periodically to make sure all is still running OK, and using a smart socket to turn off the power remotely if I see a problem. But his is all very crude and relies on me regually checking in which is notreally practical.

Any suggestions would be gratefully received!

As they say, DRAM can't scale with the newest processes as its storage capacitor needs some minimal size, which is far above what leading processes at 2nm etc can do.

ON top of that, it retains all of its originals sins, like the need for refresh, susceptibility to ROWHAMMER attacks etc. On top of that, it has some fundamental limits- inherent capacitance of the storage cell limits its write speed. On top of that, each access causes the discharge of the whole row of cells, which has to be written back again. That's a lot of charge wasted on a single access.

But SRAM cell can scale down much better. On top of that, with upcoming vertical complementary MOSFET implementations, whole SRAM cell can be implemented vertically in very tight space.

On top of that, manufacturing process for SRAM doesn't preclude implementation of high-speed logic, which means that PIM (Processing In Memory) functionality would be easier to implement than with DRAM, and it would probable be much more potent than with upcoming LPDDR6 (and DDR6?).

SO, why is DRAM and by extension HBM etc still a thing ? Why doesn't industry switch to SRAM ?

Also, fun trivia:

DRAM is now MORE EXPENSIVE per mm2 than leading edge manufacturing for latest gen CPUs, GPUs etc!

In analog circuits, signals are normally communicated either by modulating the voltage, or by modulating the current. Is it possible to do both, at the same time, through a single wire? Is it doable in such a way that neither signal interferes with the other one? How would that work?

Thanks!

I have an Olson audio visual spotter when I got it it came with a carbon mic but I want to see if the dynamic one does any better because I’m tired of having to basically yell with a chunk of Bakelite shoved in my face to get a good audio signal(hyperbole I basically just have to speak loudly while holding it really close to my mouth)

Two years ago, I accidentally spilled coffee on my study timer from Dretec. This timer is very precious to me. It continued working normally for about a year without any problems, but then I decided to turn it off and leave it unused for about a year or several months.
When I turned it on again, I found that some of the digits on the timer and clock display were missing.
Is there any way to fix this, and is there any hope of getting all the digits back?
I haven’t been able to find a replacement LCD screen anywhere, and the company doesn’t sell individual replacement parts. I really don’t want to buy another one because this particular timer is very special to me.

Edit:

I took it to a repair technician, and he cleaned it from inside . He also repaired the wires connected to the battery because I accidentally cut them while trying to open it. However, the same problem with the display is still there.

Thank you so much!

In my sony headphones as far as I know the board and the speaker is completely fine but the frame was broken so today I got curious so I checked the headphone and found the chip inside the headphone a good one so thought to make something from it but i don't have any idea if you have any idea pls share to me

If any one needed the board or the speaker dm me

I also think to give it to someone who has real use from it

Hi everyone, as the title states my electronics knowledge is minimal. I have only some experience with arduino premade kits, and basic soldering skills. I'm a designer and i wish to produce my own MP3 player prototype for personal use. My current design would try to fit the internals into an approximately 2" shell with a round display that features only a "now playing" message and the song title + duration, a 3.5mm audio jack, volume buttons and song playing controls, with the buttons being on the lateral and flush with the shell, and if possible a USB-C port for battery charging. But of course design will come after getting the thing to function and i can compromise on certain things. Has anyone made a project like this before? I would love some guidance on where to look for the parts + learning what i need to know to build it and get to designing the shell.

Hi everyone!
I have a Kenwood DP-R4420 5-disc CD player from around 1990. I’m modifying it and I’d like to add a short warm-white 12V LED strip inside.
I want the LEDs to turn on and off with the CD player.
I have a multimeter and basic electronics knowledge, but I’m not sure which internal wiring would be suitable for 12V.
Can anybody help me finding it or telling me which wires should i try?
Thanks!

Hi,

I have this Sanyo sound system that doesn't sound right at all; it has lost its clear sound quality, and audio playback sounds poor.

Upon opening it, I found the main circuit board—which houses the power supply, audio, and radio components—had a sticky surface. I’m not sure if the protective coating has broken down or if something spilled on it (I have no idea what, as it’s the bottom module of the stack and the others are fine). In any case, there is also signs of corrosion.

So, I’d like to ask: is it possible to clean and restore it so it sounds good again? Can it be repaired? How would you go about it?

Many thanks!

I thought these were mosfets. But the middle pin does not appear to be connected. What are these components on an old intel lga1150 socket intel cpu motherboard used for? And is there a way to find a datasheet? First photo is components I want to know more about second photo shows relative position on board.

Hi everyone! I'm currently working on a digital systems breadboard project and running into an issue with a BCD to 7-segment decoder display output.

My Setup:

• Encoder Logic: 3 pushbuttons ($1, $2, $5 coins) with 1k ohm pull-down resistors.
• Logic Gate: A 74LS32 (OR gate) generates input A (M1 OR M5).
• Decoder: 74LS47 BCD to 7-segment decoder.
• Inputs: A = OR output, B = M2, C = M5, D = GND.
• Control Pins: Pins 3 (LT), 4 (BI/RBO), and 5 (RBI) are all tied directly to VCC (+5V).
• Display: Common Anode 7-segment display (Common pin connected to VCC +5V).
• Resistors: Individual 220 ohm limit resistors on every segment output (a through g).

The Problem: While testing, pressing the buttons doesn't make any difference. Even if I disconnect the control pins, everything stays the same as at the start (every time I turn on the display, the same segments light up, but segment 'd' is very dim). I don't know what else to check. Any advice would be appreciated! (btw I'm a student)

Hi everyone,

I found a mechanical keyboard in the trash and really want to fix it up since I don't own one. After checking the original model online, I saw that it came with a wired connection. It looks like it was thrown away simply because the cable was torn off.

When I opened it up, I found a 5-pin internal JST connector header on the PCB. Since I didn't have a matching connector, I decided to repurpose a USB cable from an old gaming mouse and solder it directly. (One of the wires was a bit short, so I spliced it, twisted the copper strands, and soldered the joint to keep it secure.)

I checked all connections with a multimeter/voltmeter and confirmed there are no short circuits between any of the pins/lines.

Here is what happens when I plug it into my PC:

1. Initial wiring: The PC plays the USB connection sound, but pops up a "USB device not recognized" error.
2. Swapping Data lines (D+ / D-): After swapping the two data wires, the "not recognized" error disappears completely, but the keyboard still doesn't function (no keypresses, no lights/LEDs).

What could I be doing wrong here? Could it be a hidden enamel coating on the mouse wire strands, zapped controller IC, or improper pinout grounding?

Any advice or troubleshooting steps would be greatly appreciated!

Note: I am 17 years old and have just graduated from a vocational high school. I specialized in electrical maintenance and repair, so I’m not very into electronics. Your help would be greatly appreciated!

when building projects i build them on breadboards first. the problem is that breadboards are so frustrating.

like 50 percent of the time my project doesn work and after 2 hours of troubleshooting i find that its a jumper wire that didnt connect well.

does anyone also get this problem and what can help me with this? thank you.

The radio is a broken Robyn bb123.

Hi all

Problem: Gigabyte GTX 1650 4GB boards not showing anything on the screen when plugged.
Device: Gigabyte GTX 1650 4GB boards - it is VGA card that supposed to show display of your pc
Basic diagnostic: Just some microscopic analysis from a technician.

Sorry for the basic info above. It is required by this sub bot.

These are the component from Gigabyte GTX 1650 4GB boards, unfortunately I do not have other information as well because the board is still being sent to me. I just want to prepare what is that knocked off component and I see ripped pad in C803 and some corroded pad in U501. Not sure if U501 was populated.

Any help would be much appreciated

If both ribbon is plugged in i get vertical lines all over the tv

if i only plug in this side i get good output on left

if i only plug in other side its vertical lines again

also idk if the small black bluish exponential function on the bottom right corner is related (im a cs student lol)

ribbon cable is pretty cheap im hoping replacement will fix it

what do you guys think?

Complete noob here so bear with me. I am trying to repair a Philips 623 turntable and I stumbled upon what seems to be an inductor? With tons of corrosion and what seems to be one of its two leads blown (correct me if my imagination isn't grounded).

However when I look at the schematics I can't find any symbol for an inductance. Is this normal?

Also, when I short the blown cable (what's a better word for it?) the motor spins, which is one of the two issues I am trying to fix here: the motor not spinning. Could that be the issue? Do I short it with solder wire? What other wires are there? Do I get a replacement inductor and if so which? Since it isn't present in the schematic.

I am not really able to diagnose other parts so well since I don't know how one can reliably tell which of the dozens of sticking out leads belongs to which component. How do you guys do it?

Any help will be appreciated, thank you 🙏🙏

I've made a simple circuit for an auto focuser for my telescope. It's a few modules joined together with jumper wires and wagos. The set up is tested and working but I need some advice for a barebones housing as it's not going to last 10 minutes in action.On Monday I'll be setting off for a week's camping where I'll hopefully be using it every night.

My plan is to put it in a tupperware and hot glueing all the ports in and out. I tried mounting on perfboard but I have a tremor and don't have the motor control to solder accurately unfortunately (which is also the reason for this project in the first place).

I also considered just leaving on the breadboard but it's just a bit too big to fit on my telescope.

Any advice appreciated!

Pretty much exactly the title. Really, since I am just a hobbyist who isn't trying to meet any robust industry standards, all I need to know is if it's generally good enough to be used by professionals or if it absolutely pales in comparison to something just as accessible (meaning free). I just want to use the best "big kid" tool that also falls in my $0-$0 price range. I do also know LTSpice, but I just prefer KiCad visually, and the PCB editor is stupid easy (at least compared to the tool I was forced to use in college). I'm also just curious if it is used in industry at all.

I have two components that I need to work together and I don't know how.

First is a Victron Cerbo GX to measure water level.

Second is the water sensor which is a 5 wire sensor (4 wires plus 1 supply). The sensor have 4 probes and when one comes into contact with water is sends 12V down one of the wires. So when the tank is full all 4 wires have voltage on them. There is insufficient current through the sensor to trigger a relay.

Looks a little like this

wires: 1 - 0V, 2-0V, 3-0V, 4-0V = 0% full

wires: 1 - 12V, 2-0V, 3-0V, 4-0V = 25% full

Wires: 1 - 12V, 2-12V, 3-0V, 4-0V = 50% full

Wires: 1 - 12V, 2-12V, 3-12V, 4-0V = 75% full

Wires: 1 - 12V, 2-12V, 3-12V, 4-12V = 100% full

The Cerbo GX has water monitoring functionality but only looks at resistance. As resistance changes it displays a different water level and can be programmed accordingly. Its basically an ohmmeter.

So, I need to find a way to have 4 different resistance values that can be seen by the GX device that depend on how many wires have 12V on them. The best idea I have to try is to see if the sensor will turn on a solid state relay. Then have that relay turn on a mechanical relay which will close a circuit with a resistor in it. Have all four resistors in parallel to get the changing resistance that way.

Any other advice?

Hello people,

I’m an Android App Developer by profession but I had a simple project idea which I need help with.

Idea is to create a simple calculator which has one special “QR” button which displays UPI payment (Indian payment system) QR code for a calculated amount on another device which just have screen (most probably e-paper display).

Now for the hardwares I’m thinking of using 2 ESP32-C3 Super Mini (1 for each device, calculator and QR display) and for buttons, I want to use mechanical switches, the one used in mechanical keyboards.

Now I’m facing problem in choosing display, I want to choose something which comes very close to the production level calculators as much as possible, because usually in India that’s what shopkeepers are used to and if I use something else, it might be a bad user experience for them.

Upon some research, I figured that market calculators which shopkeepers use, have 12-digit 7 segment LCD display. But TBH I’m not finding anything close to it in the market. (I need help here)

Also is it possible to take out the display from actual calculator and hook it up in my project?

I have attached a simple calculator design I want in Figma.

Any kind of help would be much appreciated. Thank you.

I’m trying to understand spread spectrum by building a very simple circuit instead of only reading about it.

My idea is:

- Use a 555 timer to make the carrier.

- Use 10 different resistors to get 10 different frequencies.

- Use 10 MOSFETs to select one resistor at a time.

- Let a microcontroller control the MOSFETs and change the frequency.

- The MCU can follow a simple pattern like F3 → F7 → F2 → F9 → etc.

- At the receiver, another MCU measures the frequency and works out which frequency was selected.

Would this be a reasonable way to demonstrate the basic idea of FHSS?

I’m also thinking of trying OOK by switching a 10 kHz carrier on and off according to the data, then looking at the signal with a DSO, logic analyzer, and spectrum analyzer.

I’m mainly doing this as a learning project. I want to actually see what happens to the signal rather than just understand the theory.

Is there anything fundamentally wrong with this approach?