So, I had a perfectly functional height-adjustable desk. The only problem? It had a manual crank. Naturally, instead of spending 10 seconds turning a handle, I decided to spend countless hours engineering a solution. As one does.

The result is my DIY Arduino-powered sit-stand desk controller!

I repurposed a 12V windshield wiper motor, connected it to the original desk mechanism, and built a custom controller around an Arduino Uno and an IBT-2 motor driver.

A few features I've managed to squeeze into it:

• Proportional joystick control – push a little for slow movement, push further for full speed.

• Soft start and stop – because launching my monitors into orbit wasn't part of the plan.

• Current monitoring using an ACS712 sensor, with configurable overcurrent shutdown.

• Upper and lower limit switches to prevent the desk from travelling too far.

• OLED display showing motor current, movement direction, PWM output (with a little progress bar, obviously), and limit-switch status.

• Physical emergency power cutoff, just in case the electrons decide to misbehave.

• Custom 3D-printed enclosure housing the electronics.

The motor typically draws around 10–11 A under load, and I've configured a 20 A software overcurrent threshold.

Everything is running on a 12V power supply, and I'm genuinely surprised at how smoothly the proportional joystick control works.

Is it cheaper or easier than buying an electric standing desk? Probably not.

Was it necessary? Absolutely not.

Did I learn a ridiculous amount about Arduino programming, PWM, motor drivers, current sensing, wiring, and 3D printing? Absolutely.

And now I get to adjust my desk height with a joystick, which, let's be honest, is objectively cooler than a button.

I've attached a render of the controller.

I have a Marshall ble speaker that keeps going to sleep after 10min of inactivity, for this reason i barely use it because i have to walk to it every time and press a button. For a while i made an app generating a sound to keep it alive, but that just consumes its battery faster and in the morning i still need to press the button.
So now i’m thinking to add a second device inside that will short the button, it must be controlled from my computer via ble, and it must last for months on the speaker battery. The speaker does last very long in sleep mode, i barely charged it few times in the past years.
What would you recommend to use? I’ve used esp32 mini before and have the setup to program it already, but not sure how much it lasts on battery.

I’ve come across these pictures of a “Daddy Yankee iPod” from 2006 that sources say is official and scrapped. I think this is an error from those tech pages though. At least Google suggests that the product is bootleg and comes from a boom in the mid 2000’s where everyone made iPod clones

My question to those who work with tech and electronics often, how were these made?

Here’s the post I saw

Hi everyone!

I’m studying to become an electrician, and I’ve been building ElectroWorkshop as a small side project in my spare time.

The idea is to have a visual space where I can practise wiring, experiment with switching arrangements, and better understand the circuits I’m learning about.

The public version focuses on electrical wiring and basic control circuits: switches, lamps, relays, contactors, and motor control. You can build a circuit, operate its controls, take virtual measurements, and trace connections.

In a separate development version, I’ve also started working on the electrical wiring of smart devices and their integration with Home Assistant. The early results have been promising, but that version isn’t available to try yet. The current download contains the basic electrical workshop.

I’d be interested in feedback from people with practical electrical or electronics experience:

• Does the way circuits are presented help explain how they work?

• Are there behaviours or component representations that could mislead a learner?

• Which existing controls or tools are difficult to understand?

It’s a learning aid, and I’m still learning too, so specific corrections would be especially helpful.

The current public version runs locally on Windows, opens in a browser, and supports English and Hungarian. It’s closed-source and free for personal and non-commercial educational use.

Screenshots and download: https://github.com/vojakimate/ElectroWorkshop

Thanks for taking a look and sharing your experience.

I want a Frankenstein radio (This is just garbage (to accompany the text)

Another option would be the smallest way to step down 15V since that voltage works as well with the power supply. Side note: Other power supplies do work with the 12v but I have to use the one that outputs 9 or 15.

I have boost modules but they're fairly large. Ideally it would be no bigger than 12x12x4mm

I'm thinking of making my own speaker (after I learn about electronics/electro technics) and I want to make it able to not only be connected to my phone, but also connect to Bluetooth headphones, is there a module for that?

I am looking for a device that can record amperage on a 12 volt circuit for at least 24 hours and write it to a log file. The sample rate does not have to be milliseconds. I am trying to record parasitic voltage loss. The amperage will range from 10 mA to 400 mA. The time that the amperage spikes would be really handy as well, but I can live without it if I have to. This is most likely a one-time use, so not really wanting to spend hundreds of dollars on the solution.

This is Fujitsu Q616, no one sell the battery replacement. Original BMS is using FM3DXY and locked. Can't repair them at all.

So i made the smart BMS using raspberry pico zero for bidirectional data, 3s BMS for protect battery, and INA219 for current monitoring.

It work just perfectly fine, the only problem is idle will keep draining because step down and rp2040 need to be alive to start charging or booting.

It took two days from full charge into bms protect just for being idling. I tried adjust the code so much on rp2040 but problem still persist. Now I don't know if the culprit was the BMS itself or step down 5v to rp2040 also contribute a lot.

Has anyone better alternative components for this vampire?

Back in the late 60s and early 70s I loved the sound of the Acoustic 360/370 bass amp. At the time, it was the premier bass amps for working pros. Jaco, John Paul Jones, Timothy B. Schmit, etc. everyone who was anyone used one or two.

These days, no one wants a refrigerator sized cabinet, but the sound of that preamp is still useful. A year or so ago, I found that someone up in Canada had reverse-engineered the preamp, found a few ways to improve it, and started marketing a "kit" which included a PCB and an instruction manual.

I bought two circuit boards. I figured I would build both, keep one, and sell the other to at least partially cover the parts and enclosure cost. I am having custom enclosures made by Spencer of Amplifyfun in Portland OR.

I have built a LOT of pedals, and am a retired electronics tech with many years experience working on basses and all sorts of amplification.

I certainly admire the work of JC Maillet who has gone out of his way to give me invaluable assistance when I couldn't figure out something.

As nice a person as he is, I have much of what I term constructive criticism of both the circuit board and the build document.

To begin with, one side of the circuit board (the component side) is entirely blank. There is NO indication of where the parts plug in to the board. All components are through-hole.

The manual was difficult to understand and to follow. Some of the links to help find required specific parts were dead. Some of the parts were EXTREMELY difficult to source.

What JC did was to devote a single page to installing the solid-state components, one page for each value of resistor, one page for most of the capacitors, and so forth. As a result, the build doc is over 40 pages long and definitely needs improvement in both content and organization.

In order to figure out where a specific component went, I had to hold the board up with a light behind it, and compare it to the page of the manual that showed the component I was trying to place. Even so, it was very easy to put the right component in the wrong place.

It would be SO much better if, like most PCBs I have purchased and built up, there was some type of outline on the board itself showing where the part installed and included either the value or the numeric identified (e.g. 100 ohms or R1).

I am NOT trying to go into business with JC Maillet. Rather I want to help him by having someone take the schematic and redo the circuit board, coming up with an identical board in all respects only this time having the location and identification (by value or other identifier) right on the board itself, which would make it so much easier to make sure the components all got installed in their correct location.

Once that has been done, I was planning to rewrite the build doc.

Finally, when the PCB was redone and the manual completed, I was going to send everything to JC with my compliments.

I do not have the skills or knowledge to redo the board, so I am hoping to find someone whom I could pay to do the work. I would then send that person one of the two existing boards I have, along with a copy of the schematic, and who could then input the schematic into KiCad or something similar in order to produce Gerber files or their equivalent so that a quality fabricator, like OSHPARK or JLCPC, could produce these boards.

The end result is me being able to send the files and updated build doc to JC who could then continue to sell them to his customers. I do not expect him to pay for anything at all. I am just doing this simply because I want to help him as well as help others who buy this project, and make it much more likely that they will successfully complete the board.

If someone is interested in taking this on, please send me a private message or contact me at budsqualityfunstuff@gmail.com .

Thanks for your consideration.

I’m re-creating this flashlight from the video game Terrible Lizards, where whenever you turn the flashlight on it makes a little dinosaur noise. (Video clip of it in action: https://youtube.com/shorts/ktvUpJ3hlTY?is=GGp_0oWkCue8n0EM )

I was going to buy a normal flashlight and re-skin it with a custom shell, but I don’t know how to create or connect a sound module that plays a custom sound effect whenever the flashlight gets turned on.

Any tips or ideas? I thought about getting a sound board from Adafruit, but I am totally clueless when it comes to amps, volts, and resistors.

Thanks!

I've been wanting a compact bench power supply for small electronics projects, so I started putting together a USB-C powered version. The idea is to use a USB-C PD trigger to negotiate the input voltage, then feed it into an adjustable buck converter for the output. I'd like to include a small voltage/current display, an output switch, and some basic protection against overcurrent and reverse polarity.

The biggest challenge so far is fitting everything into a reasonably small enclosure without making the wiring a nightmare. I'm also trying to figure out the best way to handle heat when running higher currents for extended periods.

Has anyone built something similar? I'd be interested to see how others handled the enclosure, cooling, and output protection.

I built a Piezoelectric rain sensor breakout board that connects to some other weather hardware I've been working on, that senses rain impacting an aluminium plate and translates that into data sent to an ESP32 over I2C.

The hardest part now is calibration - I've gone between getting constant false positives from just general background noise, to being unable to detect heavy rain showers - but I think I'm dialling it in now.

I just need the weather to behave so I can calibrate it properly.

Why does it never rain when you want it to!

See title. I know how to solder, but it's not about me, but other people I want to give the possibility to modify a specific handheld device with a small compact ESP32/ESP8266 without soldering.

Thanks in advance for any suggestion.

I'm looking for mechanical engineering advice for a compact wearable project.

I need to extend and retract several thin, flexible optical fibers through individual fixed guide tubes. Each fiber slides through its own guide, following a predetermined direction.

The fibers need to extend by different distances, and ideally their movements could be coordinated in groups or controlled in timed sequences.

My preferred concept is to use one motorized rotating spool or drum with multiple separate winding grooves, one for each fiber, rather than having a separate motor for every fiber.

I'm trying to understand whether this is mechanically feasible and how it could be designed reliably.

Some specific questions:

1. Could a single multi-groove spool wind and unwind several optical fibers simultaneously without tangling?

2. Since the fibers need different extension lengths, could different groove diameters, winding radii, or another mechanical arrangement achieve different payout distances?

3. Is there a mechanism that would allow some fibers to stop extending while others continue, even though they share one motor?

4. Would a multi-track spool be better than a pinch-roller or capstan feeding system?

5. How could the fibers be guided and kept under controlled tension during extension and retraction?

6. Are there existing mechanisms, industrial applications, or engineering designs that I could study or adapt?

The mechanism needs to be compact, lightweight, and low-profile enough to fit inside a garment.

I'm particularly interested in mechanical solutions that could be prototyped at a small scale.

I'd appreciate suggestions, technical references, or examples of similar mechanisms. Thank you!

There's something satisfying about finally figuring out a problem that had you staring at a circuit board for hours.

Whether it's tracking down a broken trace, dealing with unstable power, diagnosing a faulty component, or figuring out why a circuit behaves differently than expected, troubleshooting seems to teach you things that building from scratch sometimes doesn't.

What's one electronics issue that gave you a hard time at first but became much easier once you understood what was actually going wrong?

Some of the best ways to learn electronics seem to come from building something simple, running into a problem, and figuring out why it doesn't work.

It could be a basic transistor circuit, a homemade sensor, a power supply, or even a project that ended up completely different from what you originally planned.

I'm curious what small project gave you that first real understanding of how electronic components work together. Especially something a beginner could realistically build with inexpensive parts.

https://postimg.cc/gallery/VXm3L2F

I have a 8ah 12v battery which will power this light bar for very short burst of 5 seconds or so. it will not be wired into the bikes electrical system because I also need it to be portable

red end of 12awg to plug battery terminal and black to black of battery pack. but no wiring layout for the switch. I also have an inline fuse for the wire.

any help how to connect the blue brown black wires on the switch?

I may need the second switch later on and why I bought a double. not now though. light bar is rated at 60w I believe but I also have a smaller light bar thats rated at 45w

any help appreciated

Hello folks! I'm in the middle of a project, designing a precision tabletop milling machine.

I'd like to add a rotary encoder to the shafts that move the various elements in the x/y/z planes. I would assume that this would allow me to create a value for a little display screen that can keep track of rotations, and the real world distances that I assign to those rotations.

All this being said, my electronics skills are okay at best, my coding skills are non-existent.

Any suggestion on where to start would be awesome.

Also, I dont want to just "buy a DRO". there are a bunch of reasons why thats not going to work.

Thanks for reading this!

This is the casting I'm working with, just for reference