Bob writes: What does one do when designing a power supply? Well, build a power supply tester, of course. One of the simplest things to build is a constant current load. This will allow for testing of the endurance of the power supply, as most of the designs out there are using slow components. However, […]
Category Archives: DIY
Remapcro: A hardware keyboard macro recorder
Anthony Lieuallen has published new build, a hardware keyboard macro recorder: Remapcro I posted once recently about the prototype of this project, but as of today I’ve finished the first real one. The name Remapcro is a portmanteau of remap and macro, because that’s what it does. It’s an array of extra keys onto which macros can be […]
DIY thermal imaging
Niklas Roy has written an article detailing his DIY thermal imaging with an IR thermometer: I did not want to hack/destroy the brand new thermometer, as I still plan to use it in its original form later. For that reason, I decided to temporarily attach an old webcam to its back. This way, my laptop can read […]
EMP Jammer build
A how-to on making an EMP jammer from JunezRiyaz, project instructables here: An electromagnetic pulse (EMP), also sometimes called a transient electromagnetic disturbance, is a short burst of electromagnetic energy. Such a pulse may occur in the form of a radiated electric or magnetic field or conducted electrical current depending on the source. EMP Jammer is a device […]
A 400W (1kW Peak) 100A electronic load using linear MOSFETs
Kerry Wong built a 400W/100A electronic load using linear MOSFETs: I bought a couple of IXYS linear MOSFETs (IXTK90N25L2) a while ago to test their capabilities when used as electronic load, and the result was quite impressive. So I decided to build another electronic load using both MOSFETs. As you can see in the video towards […]
Building an AT2XTKB (AT to XT) keyboard adapter on prototype board
Matt built an AT2XT keyboard adapter on prototype board using an AT to PS/2 keyboard cable. Project info at Matt’s Tech Pages.
DIY Arduino GRBL CNC with a laser
A DIY Arduino GRBL CNC with a laser from Bob Davis. Project info at Bob Davis’ blog.
Minstrel ZX80 clone
Dave Curran has a nice build log on his ZX80 clone, which he call Minstrel: Here is a new ZX80 clone that I have called the Minstrel. It is a fairly accurate clone electrically to the ZX80, using the same chips and the original schematic with only a few concessions to the modern world. All the parts are the […]
DIY IKEA wireless Qi charging for the Hexiwear
Erich Styger built a DIY a wireless charging system for the Hexiwear: The Achilles Heel of the Mikroelektronika Hexiwear is its charging: the charging and USB connector are only designed for a limited number of plug-unplug cycles, and it does not have a wireless charging capability like the Apple iWatch. Until now! I have built […]
Homebrew 40dB step attenuator
flathagen blogged about his step attenuator build: A home lab needs a step attenuator. It helps in evaluating RF amplifiers, filters and receivers. Both the legendary EMRFD-book, the ARRL handbook, and a variety of QST-articles provides circuit examples for building a homebrew device. Most of them follow the design principles from the January 1967 edition […]
Tiny-TS: An open-source DIY touch synthesizer
Jan Ostman has a nice build log on his open-source DIY touch synthesizer the Tiny-TS, that is available on Hackster.io: The Tiny TS is a credit card sized (100x65mm) fully open-sourced synthesizer with a 1-octave capacitive touch keyboard. Check out the video after the break.
Automation platform: ActoSenso Nodes
Viktor Takacs just published the second part of a series on his automation platform, which he call ActoSenso Platform. This second post of a series discussed about some of the nodes that can be used in ActoSenso Platform: ActoSenso Nodes are small hardware devices that are the “eyes”, “ears” and “hands” of the ActoSenso Platform. They […]
Homebrew WiFi shield
m0xpd has published a new build, the homebrew WiFi shield: Having just finished development of the new m0xpd / Kanga ESP8266 – AD9834 board, I find myself with a few WiFi components knocking about on the bench – so I figured it would be fun to try to make a WiFi shield for an Arduino… […]
Semiconductor radioactivity detector
Robert Gawron has been working on a semiconductor radioactivity detector project: Currently I’m trying to make a working version of a radioactivity detector that uses semiconductor as a sensor. It’s a different approach than Geiger-Muller detectors, more complicated, but also much more interesting. While Geiger-Muller counters can only provide information about the amount of particles […]
Big F’n 3D printer build
Dan Beaven blogged about his big 3D printer build: Summary of Features: 8 Cubic foot print volume (capable of larger with minor changes – i.e bigger cast aluminum plate) – The reason I chose 1/4″ Cast Aluminum plate was to make sure it was dimensionally stable when heated. Anything else will most likely warp over […]
36dB power attenuator for 20W
Lex PH2LB designed and built a 36dB power attenuator for 20W using PA1B power attenuator calculator: The attenuator can handle a maximum power of 20 watt and is used to reduce the power of a 5 watt transceiver. At first I did not realized why Lex designed the attenuator for 20 W. Like many HAMs I […]
100W AF dummy load
Dilshan Jayakody has published a new build: This is a quick post to showcase 100W 4 channel AF dummy load which we build to test the output stages of audio power amplifiers. This dummy load use 4, 8Ω 100W wire wound resistors which are available in eBay. In this unit all 4 resistors are mounted on […]
DIY Arduino ProMini data logger
Ed Mallon blogged about his DIY ProMini data logger build: Typical pro-mini loggers built with this design sleep at 0.25mA, before extra sensors are added. At that current draw, the logger should deliver approximately six months of operation on three brand new AA batteries with a 15min duty cycle; depending on sensor load.
Input filter and preamplifier – Jupiter modular receiver
Vasily Ivanenko blogged about his input and RF preamplifier build: Above — Build of the input and RF preamplifier stage. I put in a 0 or 6 dB attenuator right at the input. That’s double-sided Cu+ board with copper vias joining the 2 surfaces intermittently and also at crucial ground points. Project info at QRP HomeBuilder blog.
Classic vintage vacuum tube oscillator
Vladislav Damyanov shares his vacuum tube oscillator project: The above you see is a result of my work in which i tried to go Vintage with my design. I was talking about the usage of Vacuum tubes when i mention the word Vintage, am pretty sure you will agree to it as well. This vacuum tube […]