Dave Richards (AA7EE) has written an article detailing his tunable passive HF preselector: When I built the VE7BPO DC Receiver Mainframe recently, it wasn’t intended to end up as a final finished project. The intention was more to have it as part of an experimental platform. The little box that contains the DBM, diplexer, and […]
Category Archives: DIY
MetaClockClock build
Erich shared detailed instructions of how to build the MetaClockClock project, a set of individual analog ‘clocks’: The ‘MetaClockClock’ project is using multiple small dual-shaft stepper motors which are usually used in instrumentation clusters. In this project multiple such motors are interconnected on a RS-485 bus and can be controlled by a master to display […]
Over engineered true random value generator
maker_ATOM shared detailed instructions of how to build over engineered true random value generator, project instructables here: Random numbers are often used in daily for example in encryption, gambling, gaming and much more. These numbers are generated by computers using complex algorithm but it can be predicated if we know the seed value and the […]
DIY current sensor capable of handling up to 15A
Utsav shared detailed instructions of how to build your own current sensor that can measure up to 15 Amps, project instructables here: This current sensor can easily be used for measuring currents up to 15 Amps constant and can even handle about 20 Amps peak. I had previously built a shunt current measurement module using […]
DIY air quality monitor
Dejan over at HowToMechatronics shared detailed instructions on how to build your own air quality monitor: Have you ever wondered about the quality of the air you are breathing, or maybe, why you sometimes feel sleepy in the office or tired in the morning even after sleeping all night? Poor air quality can lead to […]
Laser cut project plate
Layne designed a laser-cut project plate: When I build electronics prototypes, it’s sometimes difficult to keep all the parts together without falling apart, especially if you need to move everything from one location to another. Between the breadboards, Arduino boards, programmers, FTDI cables, spare wires, and spare parts, I wanted to create a way to […]
Portable loop-on-ground antenna
Tom over at The SWLing Post shared his DIY portable Loop-On-Ground antenna.
Building a DIY High density Philips Hue LED stripe
Erich created a DIY high density Hue smart LED stripe: Philips Hue Smart LED stripes are great, but they have a disadvantage: the LED density is rather low: one LED cluster (WW, RGB, CW) every 55 mm. This leads to the problem that individual dots might be visible if the LED stripe is directly visible. […]
DIY universal PID controller
DIY tutorial on building your own universal PID temperature controller @ breadandammo.com.
A sensitive, frequency-modulated dip meter capable of measuring resonator Q
Qrp Gaijin’s version of a dip meter to measure resonator Q: A highly-sensitive, narrow-band frequency-modulated dip meter offers a simple way to measure resonator Q. I have been working with an unusual dip meter circuit recently that has some interesting properties. The dip meter, also called a grid dip meter, is a simple homebrew instrument […]
Low-cost open source ventilator-ish device
Johnny made a low-cost ventilator-ish device, that is available on GitHub: In the event that COVID-19 hospitalizations exhaust the availability of FDA approved ventilators. This project documents the process of converting a low-cost CPAP (Continuous Positive Airway Pressure) blower into a rudimentary non-invasive pressure support ventilator that could help with breathing during respiratory distress. It’s […]
Nano sheet factory
Building a nano sheet machine @ Fablab RUC Sometimes even very expensive and well build equipment breaks. This recently happened to researcher Biljana Mojsoska, a chemist at Roskilde University. She was working with nano sheets, an anti-bacterial coating for medical surfaces, as her machine stopped working. The fact that such equipment can be so expensive […]
Back to basic – Mini CNC plotter
tuenhidiy shared detailed instructions of how to easily build your own low-cost Arduino mini CNC plotter from old DVD/CD player, project instructables here. I have become too concerned with complicated details or new things, and now I should concentrate on basic, simple and important ideas. Getting back to basics, to start learning CNC, today I’d […]
DIY portable video conference, sharing and teaching device
A DIY conference and teaching device @ mcuoneclipse.com: COVID-19 is by far not over, and in Switzerland the infection rate is going up again (2nd wave?). During the spring 2020 semester university lock-down we moved pretty much everything to a ‘distance learning’ setup. With that experience and with the request to prepare for the fall […]
Build your own HF balun
Miguel, EA4EOZ, posted this great DIY tutorial on building your own balun: A balun is a MUST for dipoles or similar antennas when they are feed with coaxial cables. Many hams connect the center conductor of the coaxial cable to one side of the dipole, and the shield to the other. Wrong!From the RF point […]
DIY OpenDPS power supply
Evan’s DIY OpenDPS power supply: Years ago I heard about the OpenDPS project to give open source firmware to cheap and available chinese power supplies. These aren’t strictly whole power supplies, they are configurable CC and CV buck converters. That means that it needs a stable DC source to back it to be used as […]
How to make a very cheap VHF receiver
Sverre’s cheap VHF receiver: What is the cheapest receiver you can make for VHF? Here is a candidate where all you need to do to modify a small FM headphone receiver is to desolder one end of two capacitors, and connect a short cable with an antenna connector. See the full post on LA3ZA Radio […]
(Not a) triple tube geiger counter
Doz’ triple tube geiger counter project, that is available on GitHub: So, two little switching power supplies, one for the DOB-50 and CTC-5 as they have similar operating voltages, and one higher voltage one for the DOB-80, a simple op-amp comparator to output the pulses to an Arduino to process and display the results. The […]
The Hayes Chronograph, a remake for 2020
smbakeryt built his own Hayes Chronograph: I’ve always wanted a Hayes Chronograph, but have never been able to acquire one, so I finally broke down and just made my own. The Hayes Chronograph was a compliment to Hayes line of smart modems, and implemented a real time clock for computers that didn’t have a built-in […]
100 MHz third overtone crystal oscillator
100 MHz third overtone crystal oscillator @ DIYfan: Couple of years ago I purchased from a local store 100 MHz crystal resonator and tried several times to make a working schematic on breadboard using standard circuits I found on the internet. It never worked good enough, usually oscillating at 33.3 MHz instead of 100 MHz. […]