Erich writes: Especially in a lab or classroom environment it is convenient to start with a template project, and then explore different ways to shape the project for different needs. As for any IDE of this world, this requires an understanding of the inner workings to get it right. So in this article I show […]
Author Archives: DP
Alpha radiation makes sparks, detects smoke, and eliminates static cling
Ben Krasnow writes, “Interesting applications of a strong polonium-210 alpha radiation source. The half life is only 140 days, so the Staticmaster brushes must be replaced every year or so.”
DIY Arduino RC receiver for RC models and Arduino projects
Dejan @ howtomechatronics.com shows how to make an Arduino based RC receiver: Now these two devices can easily communicate and we can use them for controlling many things wirelessly. I will explain how everything works through few examples. In the first example we will use this Arduino RC receiver to control a simple car consisting […]
App note: Driving multiple loads with 32 kHz Nano-Power MEMS oscillators
Accomodating multiple loads from a single oscillator output discussed in this app note from SiTime. Link here (PDF) Optimizing board space and managing power consumption of wearable devices is critical in sustaining competitiveness within this fast growing consumer segment. With less power consumed, battery life is extended or provides the option to reduce the battery […]
App note: Tilt-Sensing with Kionix MEMS accelerometers
Kionix low-g acceloreometers used as tilt-sensor. Link here (PDF) Accelerometers have countless potential tilt-sense applications in today’s motion-enabled world. Tilt-sensing opportunities exist in a variety of industries, such as automotive, consumer electronics and military/aerospace, and include: • Vehicle stability systems • Inclinometers • Cell phone/PDA screen navigation • Motion-enabled game play • Tilt-enabled computer mouse/pointer […]
Inside the Am2901: AMD’s 1970s bit-slice processor
Ken posted an article taking a closer look at AMD’s Am2901 chip: You’re probably familiar with modern processors made by Advanced Micro Devices. But AMD’s processors go back to 1975, when AMD introduced the Am2901. This chip was a type of processor called a bit-slice processor: each chip processed just 4 bits, but multiple chips […]
Experimental motor driver for CG-4 German equatorial mounts
Dilshan has published a new build: This is an experimental stepper motor driver for Celestron CG-4 German equatorial mounts. This unit is functionally equivalent to the Celestron dual-axis motor driver, and we developed it as a replacement unit for the original Celestron driver. See the full post on Dilshan Jayakody’s blog. Project files are available […]
Building a 12V DC MagSafe charger
Steve blogged about his 12V DC MagSafe charger built: Now that I have a solar-powered 12V battery, how can I charge my laptop from it? An inverter would seem absurdly inefficient, converting from 12V DC to 110V AC just so I can connect my Apple charger and convert back to DC. It would work, but […]
Bidirectional detection with ultrasonic sensors
Bidirectional detection with ultrasonic sensors @ ArduinotehNiq Check out the video after the break.
#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 […]
Non-destructive testing of fuses
Kerry Wong discussed how to accurately determine a fuse’s current capacity non-destructively: A fuse is a sacrificial device for the protection the rest of the circuit in an over-current situation. There are situations we need to know with some reasonable confidence what the actual maximum current is for a given fuse without destroying it. This […]
App note: Designing RC snubbers
RLC snubber circuits, app note from Nexperia. Link here (PDF) This document describes the design of a simple “RC snubber circuit”. The snubber is used to suppress high-frequency oscillations associated with reverse recovery effects in power semiconductor applications
App note: Addressing floating inputs in digital systems (Bus Hold)
White paper from Nexperia about their bus hold tech. Link here (PDF) In the normal operations of a digital system, the input to any digital device within is clearly defined – it is either one or zero. There are however interface cases where outputs may be disabled that can result in floating inputs.
High-voltage FLASH programming on ATTINY85
ATTINY85 High-Voltage Flash programmer @ td0g.ca: The Atmel ATTINY85 is a great chip (cheap, easy to use, supported in the Arduino IDE). Unfortunately it only has 5 IO pins, which limits its usability. There are guides on using a High-Voltage Programmer (HVP) to change the Reset pin into an IO pin. However, that prevents you […]
Mechanical 7 segment display clock using an Arduino & 28 servos
Michael shows us how to build a mechanical 7 segment display clock using an Arduino and 28 servos: I built a countdown timer a couple of months ago using a two digit mechanical 7 segment display which was driven by 14 servos and an Arduino Mega. It came out quite well and a number of […]
Building a pulse oximeter
John Keefe made this DIY pulse oximeters, that is available on Github: The heart (ha) of the project is the Pulse Oximeter and Heart Rate Sensor, which includes the sensor itself, a tiny brain to make the measurement calculations, and two “Qwiic” connections. Qwiic is Sparkfun’s system of making it easier to wire up sensors. […]
An Isolated RS-422 / RS-485 Shield for the Automation Direct P1AM-100 Open-Source PLC
Glen @ bikerglen.com writes: The RS-422 / RS-485 shield is an open source shield designed to add RS-422 and RS-485 communication capabilities to the ProductivityOpen family of open-source programmable logic controllers (PLC’s) from Automation Direct. It’s loosely based on the Arduino MKR RS-485 shield but updated to use an ADM2582E 3.3 V isolated RS-485 transceiver […]
#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 […]
Deconstructing Sega’s System 16 security – part 2
Sega’s FD1089 security module reverse engineering part 2: The FD1089 module variants from Hitachi / SEGA were fabricated in a plastic case, on the back of the module a epoxy layer is visible together with two rows of pins arranged as DIP64. This arrangement mimics a standard 68000 CPU as intended by SEGA. The sample […]
App note: PoE Powered Device (PD) rectifier bridge circuits
App note from ON Semiconductors regarding different bridge rectifier topologies and how to reduce power losses in these stages. Link here (PDF) Power over Ethernet (PoE) is a technology which allows power sourcing equipment (PSE) to safely transfer power to a powered device (PD) through an Ethernet cable. The majority of the power transferred to […]