DIY NAS

A DIY NAS project from Peter Scargill: So I’ve had a fair experience of these systems. Well, this blog entry isn’t about expensive NAS systems. It’s about a cheap one… really cheap that is – and DIY. How cheap? Well, about £12 depending on what you have handy. For this price you need a handy 2.5” […]

Creating custom 3D printed LED bar graphs

Glen Akins has a nice build log on his 3D printed LED bar graphs: While building my zombie containment unit, I decided I wanted some LED displays or bar graphs to complement the containment status video running on the smaller secondary video monitor. Some other containment units used LED air pressure gauges from eBay. I […]

Build an open source laser reflection barrier

Boris Landoni from Open Electronics writes about an open source project laser reflection barrier: It allows us to detect the presence and passage of an object thanks to the combination of a laser diode which emits a light ray and a phototransistor which detects reflected light. Robotics applications and industrial control systems normally make use of optical […]

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.

DIY USB power bank from laptop battery

A DIY USB power bank made from an old laptop battery from DoItYourselfGadgets: A situation many can relate to: an empty smartphone battery and no outlet around! That’s exactly why I recycled an old laptop battery into an USB power bank. This article will show you the basic powerbank circuit consisting of Lithium cell charging circuit, […]

40 meter XCVR size of an business card with 1 watt output, 7.000 to 7.150 MHz coverage

A business card size homebrew 40 meter XCVR project from Ray Ring: I tweaked my previous XCVR design to use push button tuning and made the board layout extremely compact. I improved the side tone injection to be absolutely  perfect – not too loud, full break in and no clicks. I went ahead and integrated my switch […]

Programmable relay switch using PIC MCU (revised version)

Raj has documented his DIY programmable relay switch using PIC16F1847 microcontroller: Here are the summary of the features that this programmable relay switch has: On-board +5V voltage regulator (operates at 9-15V DC input) OFF and ON time setup for the relay operation Option for cyclic run (maximum 100 cycles, after which the timer stops automatically) […]

La Skala Arduino controlled ladder attenuator

Dimdim has designed and built his own stepped ladder attenuator, controlled by an Arduino: A few years ago I had an encounter with a ladder volume attenuator. I loved hearing the relays clicking away as they dialed-in the desired attenuation. Ever since then I wanted to design and build one for myself. The years passed, with […]

110v temperature controlled soldering station build no. 2

Mike Doughty from PCB Smoke shared his DIY 110v temperature controlled soldering station in the project log forum: This project is build number 2 of a 110v temperature controlled soldering station. It is a follow-up post to the project that I was working on last October. Blog post with complete details here. This version has […]