The miniscule event counter based on a microcontroller is built using the affordable Digispark Attiny development board. A benefit of this design is that it can be connected to its trigger input regardless of whether it is an active or passive switch. Every time the switch is turned on, the microcontroller will count the event […]
Create an inexpensive basic wireless mesh network with arduinos and long range APC220 radio modules. Wireless mesh networks have the ability to accommodate non-functioning individual nodes and are resilient in challenging environments like forests and hills, where direct data transmission between points may be limited. Step 1: How the mesh works This is a wireless
I’ve been stuck in my house filling orders for my Kickstarter campaign for the CAMERADACTYL 4×5 Field Camera, mostly just babysitting printers, changing filaments and adjusting extruders every few hours. This has left me with some rare time for tinkering. Recently I built a cheap, quick and dirty tool to calibrate a project that I was
How to build a simple Arduino shutter speed tester – by Ethan Moses Continue Reading
I’ve used this simple circuit several times to drive motors (like in my Stair Climbing robot) as well as solenoids. I originally picked it up from this instructable which is focused on controlling a solenoid. I wanted to isolate this circuit in its own Instructable as a motor driver so I could easily reference it
Although infrared communication might look like the technology of the 1990s, it is still present in a multitude of applications around us. Every time you press the button of a remote control, it is most likely it is using the IR (infrared) technology for transmitting data. The TV remote is the most common example. Air
In Part 1 of this series, we demonstrated how to send signals using soft or Simple Infrared PWM on Arduino. In our Part 2 post we looked at sending RAW IR signals – specifically a RAW NEC signal and a longer RAW Mitsubishi Air Conditioner signal using soft PWM. We have since improved the PWM
Simple Infrared PWM on Arduino, Part 3 – Hex IR Signals Continue Reading
After playing around with the SynthNV signal generator/power detector discussed in the previous post I realized what a useful a tool it is for RF testing. While its a terrific tool for VHF/UHF/Microwave testing, the SynthNV has a couple of serious limitations for amateur use in the HF region – the signal generator has a minimum
I published this schematic long ago in this article: Adjustable power supply and since then I made some improvements in PCB to make the board as small as possible. The idea is to be easy to attach the whole board to the heat sink which we want to monitor. The board is only 27mm x
When working with discrete JFETs, designers may need to accommodate a large variation in device parameters for a given transistor type. A square-law equation is usually used as an approximate model for the drain-current characteristic of the JFET: ID=β(VGS−VP)2, where ID is the drain current, VGS is the gate-to-source voltage, β is the transconductance parameter,
DC-DC converters are widely used components that convert DC power from one voltage to another, producing a regulated output voltage. These devices are used in many electronic products, including laptops, mobile phones, and instrumentation. Like any device, DC-DC converters need to be characterized by manufacturers and by engineers evaluating them for a design. Given the
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