Thursday, September 29th, 2016
A 40 dB attenuator project by Hartmut DK5LH. Hartmut uses the attenuator to measure the power of his transmitter (2 watts) with a power meter for -80 dBm to -10 dBm The attenuator is used to reduce the output power of the set to a value that is less than 0.1 milliwatt....Tags: 40 dB, DK5LH, Fast attenuator
Posted in DIY | 1 Comment »
Tuesday, September 27th, 2016
Dilshan Jayakody has published a new build: When working with expensive speaker system, speaker protector is an essential item to avoid any damages to speakers. In this project we build low cost speaker protector by using NEC's μPC1237 IC. The circuit in this project is based on μPC1237 datasheet and...Tags: protector, μPC1237
Posted in DIY | No Comments »
Wednesday, August 31st, 2016
Bob Davis has been working on rebuilding his DIY CNC machine: I have been busy rebuilding my DIY CNC machine. It will be all metal when I get done. It will also include a USB interface, likely an Arduino. None of my computers have a parallel port these days. So something...Tags: CNC
Posted in Arduino, DIY | No Comments »
Wednesday, August 31st, 2016
Scott from SWHarden has published a new build: Today I made a high frequency multiplier using a single component: the ICS501 PLL clock multiplier IC. This chip provides 2x, 5x, 8x (and more) clock multiplication using an internal phased-lock loop (PLL). At less than a dollar on eBay, $1.55 on...Tags: frequency multiplier, ICS501
Posted in DIY | 3 Comments »
Saturday, August 27th, 2016
A simple DIY dummy load project from Flathagen: I have created a simple 50 Ω dummy load to test transmitters. I also added a simple RF diode detector so I can measure the peak voltage, and calculate the power. The dummy load consists of eight 100 Ω resistors rated at...Tags: amateur radio, ham radio, homebrew
Posted in DIY | 3 Comments »
Thursday, August 25th, 2016
Bithead942 blogged about his R2-D2 build: To really bring R2-D2 to life, I knew I had to do some great sturff with electronics. I started with a Taranis X9D controller and a pair of X8R receivers configured for a full 16-channels. I chose this platform mainly for its versatility, but...Tags: R2-D2, robot
Posted in DIY, robotics | 2 Comments »
Thursday, August 25th, 2016
Sandeep_UNO posted detailed instructions of how to make this mini CNC 2D plotter using scrap DVD drive, L293D motor shield and Arduino. Project instructables here. Check out the video after the break. (more…)Tags: CNC, instructables
Posted in DIY, how-to | No Comments »
Tuesday, August 23rd, 2016
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...Tags: DIY, how-to
Posted in DIY, hacks | No Comments »
Tuesday, August 23rd, 2016
Scott from SWHarden has published a new build: Line driver chips are one of my go-tos for quickly amplifying digital signals because they’re so fast to drop in a breadboard and they provide a strong output with very high impedance inputs and need no external components. Individual buffer of the...Tags: radio frequency
Posted in DIY, RF | No Comments »
Saturday, August 20th, 2016
LuckyResistor made a miniature music machine -the outmoded sequencer project and wrote a post on his blog detailing its assembly: I just started an interesting new project: The Outmoded Sequencer Project. It is an minimalistic music machine. You can use a 8×8 “programming” matrix to create simple melodies which are...Tags: music
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Tuesday, August 16th, 2016
Flathagen writes: Interfacing dekatron tubes with a microcontroller is fairly easy, once you understand how the tubes work. Threeneuron's Pile o'Poo of Obsolete Crap provides the necessary background information and schematics for making this work. I used two russian OG-4 tubes. I prefer the orange look of the neon tubes...Tags: Arduino, dekatron
Posted in Arduino, DIY | No Comments »
Tuesday, August 16th, 2016
Facelesstech made a light following bristle bot and wrote a post on his blog detailing its assembly: There is one thing missing from all my projects so far…..Something that moves. Bristle bots are very similar to hex bugs but are built from toothbrush heads and pager motors. I thought the...Tags: DIY
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Monday, August 15th, 2016
Ray Ring from Circuit Salad has published a new build, 25 watt hybrid EL84 tube amp: This is my new hybrid guitar tube amp which utilizes a solid-state input stage, DSP reverb, and solid-state phase splitter. Only the push pull, class AB output stage utilizes tubes, namely two EL84’s run at...Tags: amplifiers
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Thursday, August 11th, 2016
KA7OEI writes: The avoidance of overcharging is usually pretty easy to avoid: Just use the appropriate charging system - but overdischarge is a bit more difficult, particularly if the battery packs in question don't have a "protection board" with them. Lead acid batteries (almost) never come with any sort of...Tags: battery, Lead-Acid, LIFePO4
Posted in DIY, hacks | 2 Comments »
Monday, August 8th, 2016
A DIY ECG made from single op-amp (LM741) and 5 resistors by Scott Harden: I made surprisingly good ECG from a single op-amp and 5 resistors! An ECG (electrocardiograph, sometimes called EKG) is a graph of the electrical potential your heart produces as it beats. Seven years ago I posted...Tags: ECG, op-amp
Posted in DIY | 2 Comments »
Wednesday, August 3rd, 2016
Saulius made a DIY PCB inspection microscope and wrote a post on his blog detailing its assembly: Despite how good microscope you have, stand is still very important part of final assembly. And while there are many commercial ones made of cast iron, they might cost more than a microscope head itself....Tags: DIY
Posted in DIY, tools | No Comments »
Friday, July 29th, 2016
An update on Pete's (N6QW) LDMOS amplifier project we covered previously: The real value of the breadboard test system is that it enables you to find/discover things that were not so obvious. Currently I have the Start & Stop buttons wired to the Arduino. I also have all six of...Tags: LDMOS amplifier
Posted in DIY, RF | 1 Comment »
Thursday, July 28th, 2016
Scott Harden built his own opto-isolated laser controller and wrote a post on his blog detailing its assembly: My goal was to utilize a free hardware output line to signal to a device that I build to modulate the laser in a special way. This way there would be no...Tags: Microcontrollers
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Monday, July 25th, 2016
Facelesstech made his own Raspberry pi shutdown button and wrote a post on his blog detailing its assembly: One thing I learn from my last shut down button was that the raspberry pi has internal pull up resistors so I didn’t need a 10k and a 1k pull up resistor on this design....Posted in DIY, R-Pi | No Comments »
Thursday, July 21st, 2016
Florian Wolters made his own version of MMDVM adapter: During experiments with digital voice mode in hamradio I discovered a nice project describing an adapter for D-Star, DMR and other digital modes based on an Arduino Due and a little PCB to be put on top. This unit is called...Tags: dmr, DStar, hamradio
Posted in DIY | 1 Comment »
