A few days ago I asked this subreddit and a few other subreddits how to fix white noise issue of IEMs while using with laptop. A lot of you suggested to get an impedance adapter. However those are very expensive despite that the device is actually a very simple circuit that can be made at home with some soldering ability.

So that's what I did and it solved the issue. I got the schematic from this guide on diyaudioheaven and made the circuit on a small piece of perfboard/Veroboard.

Things required:

1. Small Veroboard
2. 4 resistors, preferably less than 100 ohm
3. An audio socket
4. An audio cable
5. For soldering: a soldering iron and a small amount of solder wire.

Here is the picture of what I made.

https://preview.redd.it/uomy1le1qbpc1.jpg?width=4160&format=pjpg&auto=webp&s=c7dfcc427298a8b7ab5f28559f223b154dcdb809

I am not putting the image of the backside where all the connections are made because I've taped it and I am too lazy to remove and reapply and also because it won't help anyone who won't understand the original schematic in the first place.

I didn't notice any change in the sound quality however people listening to music might notice as the connections are not super precise. I use my IEMs to listen to lectures and podcasts, the white noise was getting very annoying in any long hearing sessions, which my circuit solved. In the end I am glad.

'Model 001' is a free-formed 'Talking Clock' with a strong 'Star Wars' audio theme. It also acts as a complete MP3 player.

The clock was designed as a gift to my son and reacts to a set of dates and times specific to him. An hourly chime function announces the current time using my voice and personalized messages to him.

The clock is interactive, providing a text-based interface and menus, accessible over a serial Bluetooth interface. To keep the interface secure, the clock uses a one-time password login scheme, using its OLED display to present the required login code needed from the user.

The menus hide many personal 'Easter Eggs', waiting to be discovered. It reacts to good and bad input with contextual 'Star Wars' sound effects.

The clock's main structure is built using 2mm copper welding rods, 0.8mm brass rods and 20 AWG bare copper wire were used for wiring components. The clock's electronics are commonly found electronic components, such as a Raspberry Pi Pico RP2040, a DS3231 RTC, a HC-06 serial Bluetooth module, a DFPlayer Mini MP3 player chip, a small HW-404 amplifier and a 128x64 SSD1306 blue OLED display. Two 4 Ohm / 3 Watt speakers are connected to the HW-404 amplifier and provide a crisp audio ouput.

The square wooden base of the clock provides illumination, thanks to an RGB LED as well as power for the clock itself.

The firmware for this clock was written in Go / TinyGo, along with a pure Go driver for the DFPlayer Mini MP3 chip.

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https://preview.redd.it/i3zm9yub8zoc1.jpg?width=4160&format=pjpg&auto=webp&s=bb56cdbe721b4de7837099e005eedcc9c17515bc

https://preview.redd.it/ymsxxyub8zoc1.jpg?width=4160&format=pjpg&auto=webp&s=b6cc20eacf66bd58e1d6ce6cae6be073b6b6dd83

https://preview.redd.it/hvl301vb8zoc1.jpg?width=4160&format=pjpg&auto=webp&s=d038e186a6c0d8f864e5128a2657d27ef7948863

https://preview.redd.it/zid2wzub8zoc1.jpg?width=4160&format=pjpg&auto=webp&s=b82da579c58e040bd75f4e2f76ceb320e7189993

I just finished the Ben Eater 8-bit CPU implementation using Logisim. I had a ton of fun doing this and being a mechanical engineer, I learned a lot. I'm planning to do extend this to have dedicated data, address and instruction bus in the next design. God, I love how CPU works.

Project

On the photos you can see the display module I made hooked up to my Arduino. I’m working on the boost and MCU board now, this is also my fist PCB design and I’m so proud of it!

More infos, pictures and gerber here

Open to anything, including discussions, complaints, and rants.

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To see the newest posts, sort the comments by "new" (instead of "best" or "top").

...My stuff!

Primarily second hand, ham-swap things and bobs, apart from the soldering iron and the power supply up above the bench. All things restored and repaired myself since I was a scrawny 15 years old with a soldering iron and lots of patience.

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Bench surface (way tidyer than usual)

Partial workshop area (sorry for the bad lightning)

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It's a little different now but still relevant.

The little 3D printed component storage drawers are awesome for resistors and capacitors and stuff. I have a hot plate and air gun and microscope not pictured for when I do SMD work but thats not super often right now

My first ever breadboard kit arrived today and this is my first circuit. I'm a full grown adult but still jumped and smiled like a kid when it actually turned on!

Hi everyone,

I recently published the first version of an open source project I've been working on. It's an electronics part inventory software - completely free and open source (https://github.com/PartPilotLab/PartPilot). I've originally made it for my brother, as he was f*cked up with ordering parts he already had or noticing that he actually doesn't have the part while assembling the project. All existing solutions were either expensive or shit. So I made an alternative. It has pretty much all the most important features and directly integrates with LCSC (but still lacks a bit).
Would love to get some feedback and maybe some of you would be willing to contribute :) Leaving a star would also mean a lot ✨
Lenni

Using cd4060 with 32.768khz crystal ocsilator to generate 1.000hz if anyone wnats the schematic diagram just leave comment

555 timer latch, inverters + "AND" gates + one buffer for the buzzer

Open to anything, including discussions, complaints, and rants.

Sub rules do not apply, so don't bother reporting incivility, off-topic, or spam.

Reddit-wide rules do apply.

To see the newest posts, sort the comments by "new" (instead of "best" or "top").

I was looking for a place to put this where it would be sufficiently on-topic. I hope this sub is the place? I have the above named amp. It had been working (and powered up 24x7) for many years. After a 3 hour power outage recently, it would not power on.

Searching online found many folks mentioning C196, a 220uf 35v cap as the likely culprit. Being powered on 24x7 seems to be a factor in failure as well, but then again, the amp is usually a top choice for installed commercial sound.

Seems like the cap is under voltage rated, at least one person measures ~36v across it. I was told to use caps with a voltage rating of about double the actual circuit voltage in order to be safe.

Long story short, I pulled C196, it failed out of circuit testing, so I replaced it with a two-dollar 60v 10% 220uf cap. That was it, amp works and it's back in production.

Just thought I add my experience as this is yet another case of an apparent weak point in the design of an otherwise very nice amp. TY very much.

Recent discussions led me to read Marie Kondo. So I've removed everything that didn't bring me joy. What remains, a dummy load I made (never used).