The Seven Sensors And Breakout Boards To Avoid In A Product

August 2, 2026 by Maya Posch 59 Comments

We’ve all seen these sensors and modules kicking around, as part of beginner kits, strapped into prototypes and potentially even in products deployed in the field. Yet as [John Teel] rightfully points out in a recent video, most of these have no business ever being used in a real product, and might not even be suitable for prototyping.

First up is a combination of the related DHT11 and DHT22 temperature-humidity sensors. As common as these are, they’re also pretty sketchy with their proprietary one-wire protocol and at most questionable accuracy, worsened by not having a good supply chain. The replacements are plentiful: the SHT40 and SHT41, the Bosch Sensortec BME280 or BMP180, as well as TI’s HDC3020. These get you standard I2C communication and a supply chain plus a datasheet you can trust.

Second is the HC-SR04 ultrasonic distance sensor. Although fine for prototyping, it’s a 5 V module, lacks temperature compensation and other features that’d be needed outside a temperature-controlled room. Here ST’s VL53 Time-of-Flight sensors are a good alternative, containing a range of sensors of which we covered the fancier VL53L5CX previously for 3D scanning a room. Of course, you can also use reflective IR as a good cheap alternative.

Third is the HC-SR501 passive infrared (PIR) motion module. This one is also fine for PIR and motion sensing prototyping, but is too inconsistent and power-hungry for production. Instead you can get much better and much smaller PIR modules, like the Panasonic EKMC and EKMB, or the ST STHS34 IR motion and presence sensor.

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An In-Depth Comparison Of Hobby PCB Manufacturers

October 13, 2023 by Richard Baguley 46 Comments

[Icamtuf] has been working on a prototyping run of a project, which involves getting PCBs made by several low volume PCB manufacturing companies. After receiving the boards, he analyzed the results and produced an interesting analysis.

The project he is working on is Sir-Box-A-Lot, a Sokoban gaming console clone that we’ve covered before. It uses an AVR128DA28 microcontroller to emulate the original box-pushing game and drive the OLED display. He ordered PCBs from OSHPark, DigiKey Red, JLCPCB, PCBWay and Aisler.

OSHPark boards are gorgeous, but you pay for it.

There were pros and cons for each of the services: OSHPark produced the nicest-looking boards, but at the highest cost. DigiKey Red had a flawless solder mask, but a rather sloppy-looking silkscreen and shipped the boards covered in adhesive gunk. JLCPCB was fast, shipping the boards in less than 7 days, but the smaller details of the silkscreen were blurry and the solder mask was thinner than the others. The solder mask from PCBWay was very slightly misaligned but was thicker than most, and they were the only ones who queried a badly shaped hole to see what [Icamtuf] wanted to do: the others just made assumptions and made the boards without checking.

To be fair, this analysis is based on a single PCB design ordered once and it is possible that some companies were having a bad day. These were also delivered to the US, so your delivery times may vary. So, there are no clear winners and I wouldn’t make a choice based on this alone. But the analysis is well worth a read if you want to know what to look out for on your own PCBs.

Ten Projects Won The Refresh Work-From-Home-Life Round Of The Hackaday Prize

July 27, 2021 by Kristina Panos 3 Comments

Here we are, a year and change into this pandemic, and if you were new to working-from-home every day at the start, surely it has lost its luster by now. We asked you to stand back and assess what can be better about WFH life and you took it from there, building incredibly useful things we couldn’t have dreamed of. From a pool of more than one hundred entries, the judges have selected ten projects whose creators have each been awarded a $500 prize, and will advance to the final round of the 2021 Hackaday Prize in October.

Are your prototypes a mess of wires? Or do you spend way too much time making sure each jumper is cut to the perfect length? Either way, you’re better off using breadWare, which takes a standard breadboard and changes the connection process into a software solution. That’s right — any rail including the power rails can connect to any other thanks to a handful of analog CMOS switch chips.

Maybe you’d love to build the perfect keyboard to grace your battlestation, but are afraid of all that hand wiring. Make it easier on yourself by soldering each key switch to its own little PCB.

If your home office is sometimes overrun by little humans that need immediate attention, you’ll no doubt appreciate the value of a device that can deactivate your web camera and mic automatically when it no longer senses your presence.

You may have left that awful office lighting behind, but you’re still getting plenty of prolonged exposure to blue light. This project aims to head that off a bit by replicating the current outdoor light temperature with indoor lighting. And don’t forget — air quality is just as important, so crack open a window once in a while and build yourself a smart lamp that can give you hard numbers.

This was the second of five challenges in the 2021 Hackaday Prize, which means that the ten finalists linked below will have until the end of October to flesh out and polish their projects before the final round of judging. Meanwhile, we’ve kicked off the next round with the Re-imagine Supportive Tech challenge. Show us how you would make electronics and devices more accessible, as in more modular, hackable, or affordable.

Ten Finalists from the Refresh Work From Home Challenge:

If you like these, take some time to kick back and peruse the entire list of entries in this challenge. You deserve it.

Ten Projects Won The Rethink Displays Round Of The Hackaday Prize

June 28, 2021 by Mike Szczys 2 Comments

We asked you to rethink what displays can look like and you didn’t disappoint. From almost 150 entries the judges have winnowed the list down to ten projects which are awarded a $500 prize and will go on to the final round of the 2021 Hackaday Prize in October.

In a world where there’s an HD (or better) display in every pocket, it is the oddball ideas that tend to turn heads. High on that list is a volumentric display that levitates a tiny foam ball on ultrasonic transducers to draw 3D color patterns before your eyes, or the volumetric display shown above that works with a sheet of film and motors. Or how about a take on a laser projected display that uses a phosphorescent screen so that the path of the laser persists, fading in time for the next infrequent update.

Mirrors are a part of everyday life but they’re all limited to the visable spectrum. One of today’s finalists flipped the script and turned the mirror into one the visualizes heat. And we’ll be watching with keen interest as this holographic display project seeks to turn a tube of perspex into a 3D display that can be viewed from any side!

This was the first of five challenges in the 2021 Hackaday Prize and the great news is that these finalists — all of which are listed below — will have until the end of October to refine their designs for the final judging round. Meanwhile the next round has already begun with the Refresh Work-From-Home Life challenge. Show off your solutions to being productive when working (or studying) from home while still preserving your personal life and your health.

Ten Finalists from the Rethink Displays challenge:

If you like these, you’ll love browsing through the entire field of entries in this challenge.

Survey Of Simple Logic Simulators

June 10, 2021 by Chris Lott 30 Comments

A few months ago, a tweet by [Ken Shirriff] asking about simple digital simulators caught my attention. The topic came up again in May when a repair video by [CuriousMarc] featured one such simulator called Logisim-evolution. It made me want to take a fresh look on what’s out there and which features set the different simulators apart.

So today, let’s take a quick survey of a few such simulators that I found. I’m focusing on plain logic simulators, analyzing ones and zeros using Boolean logic. They are not doing SPICE-like analog analysis of transistor logic gates, but they’re still quite handy for proofing out designs.

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Winners Of Hackaday’s Data Loggin’ Contest: Bluetooth Gardening, Counting Cups, And Predicting Rainfall

May 1, 2021 by Tom Nardi 2 Comments

The votes for Hackaday’s Data Loggin’ Contest have been received, saved to SD, pushed out to MQTT, and graphed. Now it’s time to announce the three projects that made the most sense out of life’s random data and earned themselves a $100 gift certificate for Tindie, the Internet’s foremost purveyor of fine hand-crafted artisanal electronics.

First up, and winner of the Data Wizard category, is this whole-garden soil moisture monitor by [Joseph Eoff]. You might not realize it from the picture at the top of the page, but lurking underneath the mulch of that lovely garden is more than 20 Bluetooth soil sensors arranged in a grid pattern. All of the data is sucked up by a series of solar powered ESP32 access points, and ultimately ends up on a Raspberry Pi by way of MQTT. Here, custom Python software generates a heatmap that indicates possible trouble spots in the garden. With its easy to understand visualization of what’s happening under the surface, this project perfectly captured the spirit of the category.

Next up is the Nespresso Shield from [Steadman]. This clever gadget literally listens for the telltale sounds of the eponymous coffee maker doing its business to not only estimate your daily consumption, but warn you when the machine is running low on water. The clever non-invasive method of pulling data from a household appliance made this a strong entry for the Creative Genius category.

Last but certainly not least is this comprehensive IoT weather station that uses machine learning to predict rainfall. With crops and livestock at risk from sudden intense storms, [kutluhan_aktar] envisions this device as an early warning for farmers. The documentation on this project, from setting up the GPRS-enabled ESP8266 weather station to creating the web interface and importing all the data into TensorFlow, is absolutely phenomenal. This project serves as a invaluable framework for similar DIY weather detection and prediction systems, which made it the perfect choice for our World Changer category.

There may have only been three winners this time around, but the legendary skill and creativity of the Hackaday community was on full display for this contest. A browse through the rest of the submissions is highly recommended, and we’re sure the creators would love to hear your feedback and suggestions in the comments.

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Winners Of Hackaday’s Earth Day Contest: Solar LIC, Auto-Return Parafoil, & Water Flowmeter

April 28, 2021 by Mike Szczys 10 Comments

Winners have just been announced for Hackaday’s Earth Day Challenge. We were on the lookout for projects that raise awareness of environmental issues and are happy to celebrate three top winners. Each have won a $200 shopping spree from Digi-Key who sponsored this contest.

Pictured above is the Open Flow Meter by [Eben]. The build includes sensors that are submerged into a river or stream to gauge the speed at which the water is moving. It uses a commodity plumbing flow volume sensor to help reduce costs, adding an Arduino and touch screen for reading the sensors and providing a UI to the user.

High-altitude balloons are used for air quality and weather sensing. To make those sensor packages more reusable, [Hadji Yohan] has been working on a parachute recovery system that automatically returns to a set GPS point. It’s a parafoil with auto-pilot!

Power harvesting is a fascinating and tricky game. To help ease the transition away from batteries, [Jasper Sikken] developed a solar harvesting module that charges a Lithium Ion Capacitor (LIC) from a very small solar panel. Based around a ~~100 uF~~ 30 F capacitor, it uses an AEM10941 energy harvesting chip which includes Maximum Power Point Tracking (MPPT) to utilize the solar panel as efficiently as possible. The fully charged module can output regulated 2.2 V and is aimed at distributed sensor packages that can be run without any battery at all.

Congratulations to these three top finishers, as well as the b-parasite capacitive soil moisture sensor which was named as a runner up in the contest. There were 72 entries in this challenge so don’t forget to take a look at the entire field, and leave a comment on the ones that catch your eye to let them know we all love seeing details of great builds!

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