Reddit:Electronics

Thought I'd challenge myself and depart from the tired methods of buying miniscule op-amps and smack something together from spare parts, although I bought some decent-quality components from Mouser to build the final version lol

Took me about 2 hours to design and another 3 to fully work out.

This thing is run by an LC oscillator. From what I could gather, the inductor creates a high voltage at the junction between the 1K resistor and the collector of Q1, which is fed into a resistor-transistor inverter of sorts (Q2), and then run through a miller integrator (Q3). The result is this extremely clean triangle wave with only a small amount of frequency drift (I estimated about 1% over the course of an hour, but I attribute it to the half-dead battery I'm using). I won't pretend like I know every detail about how this thing works, but I honestly didn't expect it to run this well.

The schematic:

https://preview.redd.it/3vvprndwtn0d1.png?width=980&format=png&auto=webp&s=679033ea2042f039983cce1a75c19a79ab5f987a

The board:

https://preview.redd.it/qfygy19xtn0d1.png?width=1186&format=png&auto=webp&s=6ace4be47738739d2fc4a9b30768541593e20161

The result:

https://preview.redd.it/gs84nbaytn0d1.png?width=1142&format=png&auto=webp&s=d9aa86adcd16dab1e1c7a818e7858326984f4ead

My wife groomed her and I thought of you guys and gals.

My first attempt at something freeform. A couple of WS2812 controlled by a small esp32 board. The feet are connected to capacitive touch sensors to control on/off, color mode and brightness.

Ear piece no longer works on my radio after I went to the ground and landed on it causing the metal ring to come out.

Radio still works fine just not with an ear piece. What would I have to do to go about fixing this?

for the positive voltage rail its an lm317 regulator with a bd912 transistor and for the negative rail its going to be a bd911 transistor with an lm337 regulator. i heard using regulators for audio amplifiers is pointless but also not since it may remove oscilations and hum,get rid of expensive 4,7mF(or bigger) capacitors as well as give me a stable +/-20V regardless the current which may be usefull.

motor speed controller from random parts on my desk

I am starting a family or a addiction 😅 -The arduino nano with the led is a tv b gone -the orange thing is a m5stickc plus2 -the usb purple thing is a cjmcu badusb -and the white thing is a flipper zero with external antenna

If you have your TV attached to a good, mid 2000 Hi-Fi, probably you have two remotes laying around, or if you are a retro gamer, you probably have to get up from your couch to restart or turn off tour PS2. This device allows you to control all from a single remote

It respond to a received IR code with a previously programmed, corresponding IR command to control a second device. It is fully open source and there’s a github repository for all the work I’ve done so far

Hi my laptop died and started to troubleshoot it. I found capacitors in these portion of motherboard to be shorting. Upon injecting voltage on one of the caps, this chip “eHCSA” was getting hot on FLIR camera. Does anyone know what this chip is and where can I order one? Can’t seem to find any on Aliexpress