Glen has been working on a Wi-Fi enabled bicycle traffic signal project: In the first post in this series, we built a miniature LED bicycle traffic signal using 3D printing, laser cutting, a sticker, and an Adafruit Neopixel Jewel. In this post, we’ll look at bringing the signal to life using a Particle Photon. We’ll […]
Author Archives: DP
1750Hz tone generator
Dilshan Jayakody published a new build: The 1750Hz tone bursts are often used to trigger repeaters. There are several methods to build 1750Hz tone generators which including TC5082 divider, using MCUs, etc. In this post, I present another 1750Hz tone generator which I built using 74HC4060 high-speed 14-stage binary ripple counter and 7.168MHz crystal. In […]
App note: Magnetometer placement in mobile devices
App note from Kionix about magnetometer integration challenges from the mobile equipment point of view, and gives guidelines for the mounting position of the magnetic sensor. Link here (PDF) Electronic devices contain many parts which can affect a magnetic sensor. When deciding the mounting position, it is necessary to consider the types of materials and […]
App note: Using two tri-axis accelerometers for rotational measurements
App note from Kionix on utilizing 2 linear accelerometers to determine angular rotational rates. Link here (PDF) In many applications, customers would like to measure rotational motions (angular velocity, angular acceleration) in addition to linear motions. Most often, gyroscopes are added to their end product to obtain the rotational information. In some instances, customers already […]
Decap a Chinese chip at home: Clone or not?
Sjaak writes, “It has been a while before I posted something useful. On my search for obscure chips, I came around another interesting Chinese chip (which I don’t reveal yet). The chip was advertised as a cheap drop-in replacement for a American IC so I suspected it would be a clone. I wanted to look […]
Teardown of a Marconi 2305 modulation meter
Kerry Wong did a teardown of a Marconi 2305 modulation meter: I picked up a Marconi 2305 modulation meter off eBay the other day. As the name indicated, a modulation meter is used to measure the modulation characteristics of a source signal. The Marconi 2305 is capable of measuring amplitude/frequency and phase modulated signals from […]
#FreePCB via Twitter to 2 random RTs
Every Tuesday we give away two coupons for the free PCB drawer via Twitter. This post was announced on Twitter, and in 24 hours we’ll send coupon codes to two random retweeters. Don’t forget there’s free PCBs three times a every week: Hate Twitter and Facebook? Free PCB Sunday is the classic PCB giveaway. Catch […]
DIY inline refractometer
DIY inline refractometer project from Anfractuosity: The idea of this project is to image the refractometer output, then convert the position of the blue line, to a digital reading, using image processing. The idea is to measure the brix of wort during mash and sparging, so that sparging can be stopped around 1.010 SG, to […]
Ham Radio HT turns CW (Morse) transceiver
Ham radio HT CW transceiver project from WhiskeyTangoHotel.com: Really not much explanation needed; just connect as shown above. This project uses an electronic keyer, but a simple straight key/oscillator combo could also be used. Oh… and you will also need to know Morse Code.
App note: Light quality – White light parameters
App note from OSRAM on consistency of colors specifically white lights. Link here (PDF) White light is not the same as white light. When different light sources are used, color differences may become visible. To understand why this can happen, it is necessary to understand how people perceive color and light. Nevertheless, it is possible […]
App note: Ambient lighting design utilizing RGB LEDs
App note from OSRAM on using RGB LEDs or their MULTILED® for automotive interior lighting. Link here (PDF) This application note describes the advantages and challenges of utilizing RGB LEDs for ambient lighting control. Besides pointing out practical challenges, preferred solutions for RGB LEDs are outlined and discussed to assist customers with engineering design solutions.
Free PCB coupon via Facebook to 2 random commenters
Every Friday we give away some extra PCBs via Facebook. This post was announced on Facebook, and on Monday we’ll send coupon codes to two random commenters. The coupon code usually go to Facebook ‘Other’ Messages Folder . More PCBs via Twitter on Tuesday and the blog every Sunday. Don’t forget there’s free PCBs three […]
Edge-lit seven segment display
Debra over at Geek Mom Projects posted detailed instructions of how to build this edge-lit seven segment clocks: This build combines small dozens of small laser-cut acrylic pieces which fit together with very tight tolerances. It uses skinny (4mm wide) LED strips which must be soldered, bent, and then slotted in between those acrylic pieces. When […]
PocketPi MK2
A smaller thinner PocketPi from Facelesstech: Thinner with a simpler design but packing the same feature as before. At its heart is a raspberry pi zero W with a 3.5″ screen 480×320. It has all the GPIO pins available what aren’t being used by the screen. Its powered by a 2500mAh battery and has one full […]
App note: Color sensing improves look and feel of smart products
Renesas’ white paper on applications of RGB sensors. Link here (PDF) Color printers also require an accurate sensor to ensure that during calibration and printing the correct amount of ink is being deposited onto the paper—an essential requirement when the target output is for color photographs.
App note: Eye safety for proximity sensing using infrared light-emitting diodes
A guide to human eye safety for designers of consumer products, app note from Renesas. Link here (PDF) Active Proximity Sensing for Consumer products requires the use of a light-emitting component to illuminate the target object to be detected at some distance from the sensor. Typically, product designers do not want the illumination to interfere […]
Tiny thermocouple thermometer
Johnson Davies built a tiny thermocouple thermometer based on an ATtiny85 measuring boiling water: This project describes a thermocouple thermometer, capable of measuring temperatures up to +1350°C, using just an ATtiny85 and an OLED display. More details on Technoblogy.
BLE400 with the Bus Pirate
@TheGrSpy tweeted, “Bus Pirate is talking nicely to the BLE400 from @Waveshare wearing the awesome nRF51822 SoC” Get your own handy Bus Pirate for $30, including world-wide shipping. Also available from our friendly distributors.
App note: Basics on decoupling
See AVX technical note on how capacitors filter out transients in high speed digital circuits. Link here (PDF) This paper discusses the characteristics of multilayer ceramic capacitors in decoupling applications and compares their performance with other types of decoupling capacitors. A special high-frequency test circuit is described and the results obtained using various types of […]
App note: Hand soldering tutorial for fine pitch QFP devices
No SMD tools removal and soldering of QFP packages tutorial from Silicon labs. Link here (PDF) This document is intended to help designers create their initial prototype systems using Silicon Lab’s TQFP and LQFP devices where surface mount assembly equipment is not readily available. This application note assumes that the reader has at least basic […]