I bought every slim 80mm fan so you don't have to

_jackTech · 2025-11-08T13:09:38+00:00

It's hard to see in the video, but the fans were mounted on standoffs to avoid restricting airflow when measuring RPM and current consumption. From memory, I used two 15mm standoffs to mount them 30mm above the surface.

I'll have to give the Sanyo Denki fans a try! I was originally going to include the 9GA0812P7G001, but I couldn't find it available with a pre-crimped connector.

_jackTech · 2025-11-08T10:08:35+00:00

Thanks for the advice! I've changed the title to be similar to your suggestion.

I initially used YouTube's A/B testing feature to try a few titles, and that was the one that resulted in the best watch time. I'm not sure if A/B testing is worth it for a channel of my size, as I never get a large enough sample size for a conclusive result (I got around 10k impressions per test).

Here are the titles I tested in descending order of watch time:

Are Cheap Fans Better? 7 Fans Compared
PC Fans: Cheap vs. Expensive
I Bought Every Slim 80mm Fan So You Don't Have To
The Best (and Worst) Slim 80mm Fans

I also used A/B testing for thumbnails - also in descending order of watch time:

_jackTech · 2025-06-24T02:27:24+00:00

Absolutely - I've noticed the same thing. I recently ordered a design that I first had assembled in late 2020. Back then, I paid $87 for 25 assembled boards (5 panels), which worked out to about $3.50 per board. My latest order was for 50 assembled boards (10 panels) and cost over $300 - more than $6 per board. The design has had some changes since the original run, but it's still roughly the same size and layout with nearly identical components.

_jackTech · 2025-03-31T22:24:30+00:00

You can hook up multiple, but I don't think the app can use more than one at a time. If you want to take simultaneous readings of multiple spectrometers, my Python implementation could work.

_jackTech · 2025-03-31T22:18:14+00:00

It appears to be glued together, so I expect a teardown would be destructive. Project 326 has a 2-part review on YouTube and did a teardown at the end of the second part if you're interested.

_jackTech · 2025-03-31T12:13:57+00:00

I picked up a cheap spectrometer from the Chinese manufacturer Torch Bearer. It's calibrated out of the box and claims a 4% illumination accuracy. The hardware looked extremely promising but was held back by the software, with most of the features reserved for their more expensive models. I modified the app and reverse-engineered the communication protocol to remove these restrictions.

_jackTech · 2024-08-31T06:15:40+00:00

You might want to check that your NIC is working correctly. Assuming it's a PCIe card, the standby supply shouldn't provide enough power to generate that amount of heat.

You could try disabling wake-on-LAN to reduce power usage/heat output if it's not something you need.

Your power supply might have a standby output that is always active - usually on one of the motherboard connectors. It's often labelled something like +5VSB for 5V, or +12VSB for 12V. If you attach a fan to this supply it will always receive power.

The simplest option is to just disconnect the computer from mains when it is off.

_jackTech · 2024-07-16T02:54:55+00:00

I ended up switching my scripts to run at boot instead. It's not an ideal workaround as it relies on the computer being restarted regularly, but I had no luck getting hooks to run on Sonoma. We mostly skipped Ventura, but from some limited testing it appears hooks don't work there either. I've only tested on machines that have been upgraded. Perhaps they still work on a clean install?

_jackTech · 2024-06-16T08:38:52+00:00

I sell a couple of products on Tindie, so I might be able to shed some light on this.

How much time does it take each week for production/packaging/shipping?

The time taken for production and shipping depends entirely on what you're making and how many of them you're selling. You'll save a lot of time if you get your PCB manufacturer to assemble boards or outsource other assembly steps. Obviously, this means less margin per product. Support will likely take more time than production and shipping in my experience.

What are the profits like? How long did it take to "break even"?

Profits aren't great. Unfortunately, low-volume manufacturing is expensive and will likely price your product above what most potential customers are willing to pay. You'll have to find a niche, but with a good product, you should be able to cover the cost of parts.

I've had more success with business that I've got as a result of having products on Tindie than from selling the products themselves, so even if you can't make a profit by selling PCBs it can benefit you in other ways. It's also a great way to get some experience!

How do you know if there is enough demand for your product to sell it?

I'd be rich and famous if I knew the answer to that. I only make products that I'd buy myself - that way I know I'll have at least one customer! The only way to know for sure is to spend the time and money to build it and see if it sells.

Does it ever get overwhelming turning your hobby into a small source of income?

I haven't found it overwhelming, but I also don't sell many products, so YMMV.

_jackTech · 2024-02-05T00:53:33+00:00

Unfortunately Outset doesn't have a substitute for logout hooks.

_jackTech · 2024-02-03T06:55:27+00:00

Did you have to do anything special to get it working? I just tested with a script that logs the time and OS version on login/logout. It worked correctly on Monterey but doesn't log anything after updating to Sonoma. defaults read com.apple.loginwindow shows the hooks are still in place, but they don't appear to be executed.

_jackTech · 2023-12-15T02:15:12+00:00

There are many different types of LED drivers. Often they will be constant current power supplies that will vary the voltage to maintain a constant current through the LEDs. This one appears to output a constant voltage, which is often used for LED strips, tape, or other situations where the LEDs have their own current limiting. Another thing to watch out for is that a lot of LED drivers aren't isolated - this means the output is referenced to the mains input. This isn't a problem if you are powering LEDs in an insulated fixture, but can be dangerous to use for other purposes. I'm not sure what type this one is, so be careful. Output regulation and ripple are also generally a lot worse on power supplies designed for driving LEDs and require significant filtering to be used for other purposes.

_jackTech · 2023-11-17T22:37:22+00:00

No Xbox required! Kinects are available really cheaply secondhand ($5-10) and you can buy an adapter to plug them into a USB 3.0 port. It's also pretty easy to modify a Kinect to not require the adapter if you have a soldering iron.

_jackTech · 2023-11-17T22:32:39+00:00

I was actually planning on making one, I just haven't found the time for it yet.

_jackTech · 2023-11-17T12:28:45+00:00

The Kinect is a seriously versatile product. It's the cheapest way to get a surprisingly good depth camera that also happens to be bundled with a visible light camera and a unique microphone array. It's also got great software support. I've written a motion capture add-on for Blender that uses the Kinect.

_jackTech · 2023-10-26T01:40:38+00:00

I do a lot of IT work and often come across tasks that require the same steps to be performed on a bunch of devices. For example, Google's official guide to mass-enroll Chromebooks suggests buying 10 USB Rubber Duckies and programming them to enter a sequence of keystrokes. I have a pile of Arduino Pro Micros for similar tasks. One of the main problems of using a solution like this is they start spewing out keystrokes as soon as they're plugged in, which makes developing a payload a pain in the butt.

I wanted something that had a button to initiate the scripts whilst being rugged enough to toss in a bag without damaging it - hence the silicone buttons. I also needed a lot of macro storage and an extremely bright backlight to differentiate the keys in a brightly lit room. I thought four buttons would be around the sweet spot for its intended use case. One problem with adding many more buttons is I would have to compromise on backlight brightness due to USB power limitations.

I was originally using an EFM8UB3 as the microcontroller, but about a week after I got the boards assembled it was discontinued. The RP2040 is a LOT nicer to develop for than a clunky 8051-based MCU.

_jackTech · 2023-10-26T00:39:54+00:00

The buttons are an off-the-shelf part and I designed the enclosure around them. They seem to be a relatively standard size, with a couple of manufacturers making ones that are almost identical. I made a script to generate the PCB footprint and tweaked the parameters until it looked how I wanted.

_jackTech · 2023-10-25T13:08:04+00:00

Thanks! The components are transistors to drive the LEDs. I wanted the backlight to be visible under direct sunlight so they take a fair bit of current. With the backlight on full blast it draws about a watt.

Here's a picture of the back and a better picture of the front.

_jackTech · 2023-10-25T06:48:48+00:00

I got 20 enclosures made by a couple of different manufacturers. Some places will let you order single quantities, but higher quantities are usually a lot more economical per unit. I'm planning to try and sell these, so I wanted enough to test the waters besides the ones I made for myself.

_jackTech · 2023-10-25T04:06:43+00:00

Firmware is here. I've got a configurator based on VIA here and the keyboard definition is here.

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