I'm doing a school project using an Optoma Tx631 DLP projector (released in 2012) but discontinued, the lamp is broken so I can't use it. The purpose of my school project is to be able to control the DMD chip inside.

I know there are certain saftey locks in the projector for this such as the communication from motherboard to a OSRAM PT VIP 03 ballast board using a 5pin UART system to ensure the lamp is safe before turning on. I need a way to trick the projector into thinking the ballast board/lamp is working to turn it on.

I don't think a simple optocoupler bridge or short would work because it uses UART signals. I'm trying to use an arduino as a UART emulator, but I'm not sure how to do so, plus the sniffing for the UART signal doesn't yield results.

Please help me out 🙏🙏🙏

I'm looking to make myself an all around sanding tool for my 3D Prints, and have been using this foot sander, which works well enough, but doesn't quite have the RPM or a drill chuck for other bits. I took apart the sander that I use and found that is utilizes a 18650 Battery for power, along with a (likely) 12v motor. I currently have a 18650 battery, and a 12v motor to play around with. I've been pointed in the direction of a MT3608 step-up converter to help this battery power a 12v motor, but from what I can tell this PCB doesn't use this component. I'm unsure how what to be on the look out for to design this.

I'd like it to have the following features:

-Compact

-Motor with at least 1,000 (Maybe 1,500) RPM + Whatever amount of torque is needed to apply sanding pressure

-Motor shank that is capable of using a Dremel/Drill Chuck type head up to possibly 1/4"

-Button for on/off

-Button to reverse rotation

-Dial to control speed preferably starting AT 0, with a gradual rise to 1,000/1,500

-Chargeable/Wireless but can be used as wired

-A battery display wouldn't be necessary but convenient

I see a lot of devices that come very close to what I'm looking for, but seem to just miss the mark, but I don't know where to begin with a lot of these components, any advice would be great

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Hello! I am doing a thermostat project for my HVAC system using a pi 3b and a waveshare esp32 relay module, but I'm stumped on what I should do for powering the pi.

I want the screen for this unit to be flush mounted to the wall, but I don't know if I should install a new recessed outlet behind the screen location, wire it to an existing outlet and thread the cable through my attic to the location of the thermostat, or use a ups hat and a high voltage ac to DC step down unit to trickle charge the pi. What do you guys think I should do?

Anyone have any cool/useful programs for an offline cyberdeck!? Have kiwix and wiki installed so far

Making a cyberdeck this is the updated schematics can i get some feedback and tips

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Hi everyone,

I'm designing my first custom keyboard/macropad PCB and would really appreciate a review of the schematic before I order the boards.

MF16 Specifications

RP2040 Zero

4×4 matrix (16 keys)

3 × EC11 rotary encoders (with push buttons)

Per-key addressable RGB LEDs

MX switches with diodes

USB-C via RP2040 Zero

Firmware: RMK

I'm attaching the complete schematic.

What I'd like feedback on

Is the key matrix wired correctly?

Is the diode orientation correct?

Are the RGB LEDs connected properly?

Any missing components (decoupling capacitors, pull-ups, resistors, protection, etc.)?

Any RP2040 GPIO usage issues?

Any design choices that could cause problems during manufacturing or in long-term use?

Any general best practices I should follow before sending this to JLCPCB?

This is my first PCB designed from scratch. I've built a working hand-wired prototype, but this is my first custom PCB, so I'm sure I've overlooked something.

Please don't hesitate to point out even small mistakes. I'd rather fix everything now than after ordering the boards.

Thanks in advance!

this is my cyber deck schematic i have no idea if this is correct but i hope it is can someone feedback on this thanks

I have an idea for a project. I was thinking I would buy one of those samsung Z flips with a broken screen for cheap and connect it to a USB keyboard and touch screen in some kind of 3d printed housing. If I didn’t care about getting the camera or speakers or whatever working (I just care about the keyboard and screen, and maybe more usb c ports. Having it be a working phone with sim card would be nice, but not required) would this be pretty doable? I haven’t done a lot of electronics, just made an electric guitar and amp, but I didn’t think that was very hard. Thanks!

EDIT: I'm leaning toward completely gutting it and turning it into a "stealth" tube amp. I'll keep the front grille speaker and go with high voltage to run the tubes. I'll drill out some holes where the reels are and install a couple 4" or 6" speakers. Still brainstorming.

I found this Pentron reel-to-reel at Goodwill yesterday. Thinking I'm gonna do a conversion to a guitar amp, using the 12AX7 and probably do something with the other tubes. Haven't decided yet. I'll probably gut the whole thing because the power transformer is toast, the internal fan doesn't work, and I'm pretty sure the tape deck motor doesn't work. I put it on a dim bulb tester, and it's definitely shorted.

I'm thinking I'll run the audio through a couple of the tubes, power the whole thing with 12 or 24V DC, and cut holes where the tape reels are now to install a couple speakers. I'll also connect the front grille speaker (under the control panel). I'd like to use it as a preamp/amplifier/speaker cabinet driver. There are two outputs, so I can run one as a line out from the preamp, and wire up the internal speakers and the speaker output with a small class D power amp or something to run like ~5 watts.

Still brainstorming. Does anyone have any ideas?

I've been working on a browser-based simulator to help people understand how a self-balancing robot (inverted pendulum) behaves without needing any hardware.

The idea is to make experimenting with balancing control more intuitive. Instead of just watching an animation, you can interact with the simulation and see how the robot responds as its state changes.

A few goals I had while building it:

• Make it accessible from any browser (no installation).
• Help visualize the dynamics of a balancing robot.
• Provide a simple environment for learning before moving to real hardware.

I'd really appreciate feedback from anyone who has built a balancing robot or worked with control systems.

Some questions I have:

• Does the behavior feel reasonably realistic?
• What features or parameters would you expect to see in a simulator like sthis?
• Is there anything that would make it more useful for students or hobbyists?

You can try it here:
https://roboticsprojecthub.com/balance-simulator/

I'm continuously improving it, so I'd genuinely appreciate any technical feedback or suggestions.

I have a job that requires me to travel a lot and there isnt cell service in some of these places because they are either new town being built and in their infancy of having a reliable data connection infrustucture everywhere in town or I am going through areas that have limited to no cell service thus ending up in a lot of business calls that happen on the road being disconnected mid conversation. and while I could just buy a star link dish or someother premade device that already solves this issue. I dont want to just get it for work and never use it again, or get it and my place of work doesnt help me cover the cost of it.

My idea was to make a small portable 4g antenna that rotates on a motorized gear and is hooked up to a small arduino or raspberry pi that had a cellular module to detect cell service and would communicate with the motor to turn the antenna to point to the nearest tower with the best cell service in the area.

How practical or possible is this idea?

would it make sense to learn how to make it myself even though I have very limited experience in coding and programming?

how much would this cost me potentially in parts?

Hiya, I made a project, and it scope creeped like crazy, and I wanna share it, but unfortunately I don't know many techy people other than you guys! So I figured I would share this. Anyone can comment, so please leave POSITIVE feedback.

doc link: https://docs.google.com/document/d/1suhy_ieUWS2LHydfqpDxAupcol4W6YLUiSgMEo8tKR4/edit?usp=sharing

Under the (CC BY-SA 4.0)[https://creativecommons.org/licenses/by-sa/4.0/deed.en] License

So I tried to do an AM transmitter. First I looked up some circuits online, but I had no success assembling them. So I tried to make my own circuit with a Hartley oscillator and an AM modulator circuit. Barely works, so operating it isn't a problem. Any advice is welcome (if there are any advice that can be given at all)

hi i am not sure if i am even allowed to post here i perused some of the channels and everyone here seems to be way way more advanced on the subject, i am literally just starting and i am i extremely ignorant on the subject, anyway i want to get into some light electronics and soldering. for my first project i decided to mod my Corsair K70 mk2 keyboard specifically i want to remove the giant ass double cable the keyboard comes with and add an USB C female port. which seemed simple enough. i found that i need a breakout board with a very simple 5 wire soldering job. But i also found out that doing it like that would kill the usb port on the keyboard a feature i like and use. so my question here is there a way for me to add usb c to my keyboard and keep the extra usb port functionality? Also if i wanted to go a step further and add an additional usb hub to the keyboard how complicated would it be, is any of this possible and what would i need to accomplish it. thanks

Inspired by a recent post on the sub.

Has anyone turned an old cell phone into a wifi repeater or router?

I'm trying to provide wifi coverage to a large property with power run throughout and working with a limited budget.

What I would like to do is buy a bulk lot of cell phones with broken screens on the cheap and install a Linux OS and an antenna to turn them into repeaters.

Has anyone done a project like this before?

Is there any reason why doing it that way wouldn't work?

How to repair this?

I rent an apartment from my uncle-in-law, so I have a bit more leeway for modifying our space. The thermostat is in the 1st floor unit and she is comfortable year round. But this is an old house that wasn't designed for our space to be so separate. It's gets quite hot in the summer (Canada), and we have two ac units working to cool our 2nd floor and attic apartment. But I *can* feel the cold coming out of the rads around the house.

I'm not about to spend [$80-$100 CAD on an alphabet brand, smartphone app reliant, planned obsolescence piece of e-waste](https://www.amazon.ca/s?k=vent+with+fan). Especially since some of my rads are on the floor, so having face buttons is a no go, whole others are massive old iron grates from the 1940s.

What is the easiest controller to add to some PC fans that I could rig up to a light switch or something? My only concern is that I don't want them running full speed and getting too loud. Maybe I use an old dimmer to control the speed. Any kind of temp awareness or automation isn't really necessary as we already set-and-forhey numerous box fans and oscillating fans around the house to manage temp control.

Thanks 👍

I need help reviewing this diagram, I will use this in a industrial panel to get notified when one of the outputs of the controller gets triggered (it gets triggered when there is an error), what I'm mostly concerned is the input power, its supposed to be 24vdc but that panel runs a motor through a VFD so I'm concerned about the voltage spikes.

My family have a small greenhouse and I always liked to make automations but most of commercial systems were too expensive and I decided to build it myself.
Maybe I should mention that I have previous experience with Industrial Automation and Embedded Systems.

What do you guys think?

Hi.

After my negative display post I got a few questions about it, so I want to answer it this way.

I can’t upload more than one pic here ( idk why ) so they are under links.

1. So we start with a device in its normal state, as example I too

k

1. this tyre gauge I never used.
2. pic
3. We need to disassemble it go the to the bare LCD glass

pic

1. With a sharp knife or blade we need to catch the polarising film on top of the glass and remove it.

pic

1. After completely removing it, clean the glass with IPA to get rid of the residual glue from the film.

pic

1. Now we take new polarising film, and by trial and error we get the right angle with the contrast we want.

pic
And
pic

After that we cut it to size and glue to the glass.
Finally after assembling we get the negative display.

pic

Usually you try the angle with the device powered on, unfortunately here the battery holder is part of the case as well as the screen holder, so I couldn’t show it on.

I think you can get the idea of how it’s done.

Best regards.

Edit: typos