Teardown on karl

#TwoMinuteTeardown: USB-C charged AAA battery

Sun, 01 Feb 2026 00:00:00 +0000

Two Minute Teardown: USB-C charged AAA battery

First, these things have existed for quite a few years now but people still seem to be discovering them. If you are one of todays lucky 10,000 people to find out about them, you’re welcome. I hope these can change your mind about rechargeable batteries; they’re good, now!

One of mine started failing with intermittent output voltage so I decided to take it apart and see what was inside.

#TwoMinuteTeardown: Corporate Systems Engineering SSHAAC00-S041911

Sat, 24 Jan 2026 00:00:00 +0000

Corporate Systems Engineering SSHAAC00-S041911

Electric utilities can employ “load shed” devices throughout their grid to manage load. These devices are usually found on air conditioners, water heaters, pool pumps and other large electrical loads. Typically they’ll offer you a small financial incentive to allow the utility to cycle your device off for short periods of time during peak demand events.

The Corporate Systems Engineering SSHAAC00-S041911 is one such device.

#TwoMinuteTeardown: Multiple LED Controllers

Fri, 26 Dec 2025 00:00:00 +0000

Introduction

Bit of a change in format; instead of one massive post for all the misc. 11-11 teardowns, I’m grouping them. This post is the “LED Controller” group. I managed to snag the following on Ali Express:

To continue from last year’s trend, I waned to celebrate that all three of these LED controllers have:

#TwoMinuteTeardown: SLZB-MRW10

Fri, 26 Dec 2025 00:00:00 +0000

Two Minute Teardown: SMLIGHT SLZB-MRW10

To make a very long story short, I need to move away from my very old 802.15.4 radios plugged into a very old Raspberry Pi for my smart home setup. After some research, the SMLIGHT SLZB-MRW10 is new, uses modern radios and ships with firmware that makes it trivial to move packet processing into compute distributed on the other end of the network.

#TwoMinuteTeardown: Ubiquiti SFP Wizard

Thu, 18 Dec 2025 00:00:00 +0000

Two Minute Teardown: Ubiquiti SFP Wizard

Disregard note below about 1.0.5

To make a long story short, I allocated a few hours to build a tool that can read/write the SFP module’s EEPROM. I then wired this up to a logic analyzer and compared the read/write operations to what the SFP Wizard does when it tries to unlock a module.

#TwoMinuteTeardown: Hamgeek YK-1000H NTP

Fri, 12 Dec 2025 00:00:00 +0000

Two Minute Teardown: Hamgeek YK-1000H NTP

Curiosity got the better of me when browsing AliExpress and I spotted this GPS NTP server for under $100 USD.

I needed a cart-stuffer anyways so I ordered one as a backup for my existing GPS/NTP server.

While waiting, I took a look around to see if there was any additional information about who makes this / if there was a custom firmware or similar. Nope, there there is not a ton of information about the YK-1000H online.

#TwoMinuteTeardown: Duogalia AM70 Optical Fiber Multi-Meter

Wed, 10 Dec 2025 00:00:00 +0000

Two Minute Teardown: Duogalia A-M70 Optical Fiber Multi-Meter

While diagnosing a flakey fiber link, i ran into a situation where a basic “flashing red” visual fault finder was not sufficient. I needed to actually measure the optical power levels on both ends of the link to ensure that the fiber was not damaged and that the SFPs were operating within spec.

This was the cheapest tool that could be delivered quickly. The issue was found and fixed so now let’s have a look inside.

TESmart HKS801-P23-USBK KVM Teardown

Sat, 17 May 2025 00:00:00 +0000

TESmart HKS801-P23-USBK KVM Teardown

Recently, one of the USB ports on my previous KVM switch failed. Since it’s a critical piece of equipment, I needed a replacement the same day. The original AliExpress product page was no longer available; the seller seems to have closed up shop entirely.

Fortunately, the OEM—XUFUNG—has released an updated version, now sold in the US as the TESmart HKS801-P23-USBK. It looks visually identical to the previous KVM switch, but the USB ports now feature the characteristic blue color indicating USB 3.0 support.

#TwoMinuteTeardown: Petkit Eversweet Solo 2

Sun, 20 Apr 2025 00:00:00 +0000

Two Minute Teardown: Petkit Eversweet Solo 2

I am doing research for an upcoming project and was curious about how other people have solved a similar problem. This happens to be the cheapest option that was available at the time.

I am primarily interested in the pump; the integrated “low water” sensor and the UV-C sterilization are very nice features that would check off a lot of boxes for me… Unfortunately this pump it lacks both the flow rate and the head that I need for my project.

#TwoMinuteTeardown: Wozniak WPX-0001 Qi Tester

Sun, 20 Apr 2025 00:00:00 +0000

Qi wireless power tester

The Qi standard for transmitting power is ~ 15 years old and has been ubiquitous for at least a decade now. And yet, I have only recently seen any testing equipment for it.

The Wozniak WPX-0001A is a simple tester that can measure the output level and protocol of Qi chargers.

'standard tools create wonderful things' ❤️.

Please ignore the super shiny reflections...

#TwoMinuteTeardown: Panel Mount Liquid Level Indicator

Sat, 15 Feb 2025 00:00:00 +0000

Generic liquid level meter teardown

I ordered this part years ago for a project I eventually canceled.

I can’t use it for anything, and it’s just taking up space, so I’m going to open it up before I recycle it.

The Ali Express listing is a 404 so I don’t have a link to share or really any information about it.

The main thing to take away is that it’s meant to interface with a liquid level sensor. It will display the level of liquid in a tank and - optionally - trigger a few relays based on the level.

#TwoMinuteTeardown: Home Assistant Voice - Preview Edition

Sat, 01 Feb 2025 00:00:00 +0000

Home Assistant Voice: Preview Edition teardown

This is a quick #TwoMinuteTeardown post for the recently released Home Assistant Voice Node - Preview edition.

Normally, I’d be doing a full teardown, but this is a little different; the Home Assistant team has done a lot of the work out in the open. With just a quick Google, you can find official:

teardown instructions here.
source code here.
3D printable case files.
Instructions for adding custom devices here.

I am grateful for such a well-documented and open project. Truly, by hackers for hackers!

AliExpress 11.11 Sale Teardowns (2024 edition)

Sun, 01 Dec 2024 00:00:00 +0000

11-11 day teardowns (2024 edition)

I guess this is becoming a tradition now?

During China’s Single’s Day sale on AliExpress, I bought various gadgets - both for projects and out of curiosity. Rather than write separate posts, here’s a collection of mini teardowns showing what’s inside each item.

Previous years:

2023

Tuya Zigbee 3.5 Inch Smart Wall Switch

non-affiliate link

I’m always looking for a better scene controller/switch/Home Assistant interface. I was curious about which chip they used for the full graphics display and was hoping for an easily hackable Android device. Unfortunately, no such luck with this.

AKASO DL12 Dashcam Teardown

Thu, 01 Aug 2024 00:00:00 +0000

AKASO DL12 Dashcam Teardown

If the double yellow lines are in the middle of your rear-view mirror, you're doing it wrong.

This was my dashcam for a while until the front camera stopped working. It was a good dashcam while it lasted but there are better options now… so let’s take it apart!

Arizer XQ2 Teardown

Mon, 01 Jul 2024 00:00:00 +0000

Arizer XQ2 Teardown

A friend of mine reached out and asked me about automating some aspects of their aroma therapy treatment.

Note

I was not given permission to share the specifics of their medical condition or the larger treatment plan so this post is going to deal with just the technical aspects of the device.

The device they’re using for aromatherapy is the Arizer XQ2 and we agreed that integration with their existing Home Assistant setup would be ideal.

Altinex TE460-137 Teardown

Sat, 02 Dec 2023 00:00:00 +0000

Altinex TE460-137 Teardown

It is surprisingly hard to find a device that can dump details about the various protocols and negotiated standards for a HDMI connection. For how ubiquitous HDMI is, you’d think that there would be a lot of devices that can do this. There are LOADS of devices that can snoop USB and Ethernet, but HDMI is a bit of a different beast, apparently.

After a bit of searching, I found the Altinex TE460-137 could do exactly what I wanted.

AliExpress 11.11 Sale Teardowns

Fri, 01 Dec 2023 00:00:00 +0000

11-11 day teardowns

Single’s Day is a big deal in China and AliExpress has a big sale in celebration.

In addition to project supplies, I found quite a few items that can only be classified as “ohh, that looks interesting and I need another $11 in the cart to unlock free shipping…” items.

I was planing on doing a series of posts covering some of the stuff I bought but nothing on it’s own was really “worth” a full post so instead of a bunch of short “Two Minute Teardown” posts, I decided to just roll everything into this massive post.

Inside of the Pulse-Eight HDMI CEC Injector.

Fri, 01 Dec 2023 00:00:00 +0000

Inside the Pulse-Eight HDMI CEC Injector

To make a long store short, Google recently pushed a few updates to my TV that made it slow as all hell and frustratingly unusable. I finally got fed up with the laggy UI and dug out an old mini PC and installed LibreELEC on it.

Everything worked perfectly except for the lack of CEC support on the mini PC.

This is a common enough problem that there’s a few different devices out there that can add CEC support to a device that doesn’t have it. I chose the Pulse-Eight HDMI CEC Injector because it’s natively supported by LibreELEC.

ESPHome for Sonoff T5 family of Switches

Sat, 11 Nov 2023 00:00:00 +0000

ESPHome for Sonoff T5 family of Switches

It’s hard to beat Sonoff switches when it comes to well-made, affordable, Home Assistant compatible switches. Ever since they announced the T5 series, I’ve been patiently waiting for the US variant to become available so I could replace my M5 switches with T5 switches.

Don’t get me wrong, the M5 switches are great… but not perfect.

The T5 switches improve on the M5 limitations with some new and novel hardware features. Taking advantage of these unique features requires a considerably more complex ESPHome configuration than the M5 series switches.

ESPHome on the Yeelight Monitor Light Bar Pro

Mon, 18 Sep 2023 00:00:00 +0000

Yeelight Light Bar Pro (YLTD003) Teardown

Monitor-top light bars are wonderful for reducing eye strain and fatigue and the effect is even better with a bias light behind the monitor. Enter the Yeelight Light Bar Pro (YLTD003).

YeeLight marketing photo from AliExpress listing. The background wash light really does help reduce eye strain and fatigue.

Teardown and Home Assistant integration with two generic Chinese 'smart' power strips.

Sun, 15 Jan 2023 00:00:00 +0000

I love the Sonoff-S31 smart plugs. They’re cheap, well made and - most importantly - trivial to flash with ESPHome and integrate into Home Assistant. They do have one obvious draw back, though; optimized for a “traditional” US style outlet. When you try to deploy them to a power strip, you end up loosing about 50% of the outlets on the strip!

This is how you loose about 50% of the outlets on your power strip.

Quick look inside two Ali Express mmWave presence detection sensors

Tue, 01 Nov 2022 00:00:00 +0000

Millimeter Wave technology has recently hit “mass consumer product adoption” price points. A casual search for “human presence sensor” on Ali Express will turn up a seemingly endless number of sub $40 devices that can detect movement far more accurately than any old PIR sensor.

Each listing is fairly generic; there’s no explicit manufacturer details but they all use the same marketing images:

As the photos below will show, neither device is super well marked with a model number so I’ll just refer to each by either the color of the enclosure or by the radar sensor inside.

Quick look inside the OMRON Evolv BP7000 Blood Pressure cuff

Sat, 14 May 2022 00:00:00 +0000

A friend recently asked for my help with some reverse engineering. They wanted to know how difficult it would be to re-use some components from a lot of refurbished blood pressure cuffs they had recently acquired.

Sounds easy, right? At a high level, there’s going to be:

a pump and a pressure sensor and a valve
a micro controller to run the show
a way to communicate the readings back to the user

In the interest of expediting things, I asked for the FCC IDs from the devices so I could have a look inside… and was surprized to find out that there was no FCC listing for this particular model from the lot.

Quick look inside Venstar T7850 - One of the only 'no-cloud' WiFi Thermostats that plays nice with Home Assistant

Sat, 23 Apr 2022 00:00:00 +0000

Info

As of 2022-05-11, there is an update on my experience with the thermostat below!

This is another one of those posts from my never ending quest to integrate Home Assistant with All The Things!

The thermostat that was installed when I moved in was an early Nest thermostat. These thermostats are - for the most part - well reviewed and liked. I had no complaints… except one.

Inside a generic/white-label HDMI KVM Switch

Sat, 16 Apr 2022 00:00:00 +0000

If you’re here just for “how do I get it working with ESPHome” bit, skip to the ESPHome Component section below.

Update 2022.05.14

I have just uploaded a basic PCB and enclosure to the ESPHome Component Repository.

For the last few months, I have been looking for a KVM switch to simplify switching between work and personal computers. Initially, I didn’t think my criteria were that unreasonable, but for whatever reason there is no KVM switch that:

Installing Tasmota on the Xiaomi Desk Lamp

Sat, 22 Jan 2022 00:00:00 +0000

MJGJD02YL vs MUGJD01YL

There are at least two versions of this lamp. Thanks to @htvekov for confirming that the MUGJD01YL variant does not contain an ESP32. It contains a TLSR8368. Some photos of the MUGJD01YL internals are provided below.

If you’re here just for “how do I flash tasmota” bit, skip to the Tasmota section below.

Now with ESPHome

ESPHome support for the single-core ESP32 chip in the lamp has come a long way. You can find the ESPHome configuration that I used with this lamp below.

I was looking for a way to light my desk my desk without screen glare. The easiest way to prevent glare on a screen is to change the orientation of the light relative to the screen either from under or behind the screen. This is not practical for ceiling mounted lights or for any floor lamps.

Using Home Assistant to dynamically layout openHasp widgets

Tue, 18 Jan 2022 00:00:00 +0000

Background

This is one of those posts that sat in the Drafts folder for way too long. Just before release, I’d discover something new that would warrant substantial rewrites. After several delays, false starts and re-writes, I finally have something that is mostly new and worth sharing with the world.

Like with the past few teardown posts, this one also started off as a ‘cart-stuffer’ item so I could unlock a more generous discount on the total purchase. The listing that caught my eye had the generic title:

Generic RGB Wall Switch teardown

Sat, 01 Jan 2022 00:00:00 +0000

Yep! Another teardown post! This one was also a cheap “because i’m curious” post.

What

It’s a ‘decora’ style wall switch with WiFI and an RGB color changing paddle.

The product listing was very non specific:

EU US WiFi Smart Wall Switch Push Button Timer Relay Switch Voice Remote Control RGB LED Night Light Lamp TUYA Alexa Google Home

I saw TuYa in the item description and hoped that it would be based on an ESP8266 module or at least use a pin-compatible module. After all, there are a few such devices on the Wall Switches and Dimmers section of the tasmota templates repository.

Shelly Pro 4PM teardown

Sat, 01 Jan 2022 00:00:00 +0000

Yet another teardown post!

Curiosity got the better of me while putting together a BOM for a project and I decided to add one of the new Shelly devices to my order to bump the total over the threshold for a nice discount.

I have not seen a ton of discussion about what’s inside of a any of the new Shelly Pro devices. These ’next generation’ devices appear to all use a common and more uniform API which, apparently, is too demanding of the ESP8266 based hardware so it won’t be backported.

Tuya Smart Curtain Driver Robot Teardown

Sat, 11 Dec 2021 00:00:00 +0000

I am trying something new out with this post; some mix of hardware teardown and a brief product review.

Why

I was looking for a way to actuate some heavy blackout curtains.

There have been several DIY projects out there that manipulate curtains but they all appear to be relatively involved as they are often designed for a very specific type of curtain; servos that fit on the ’tilt rod’ or motors that can manipulate the pull chain… etc.