Adding A Backlight To A Cheap Multimeter

June 11, 2015 by Rick Osgood 15 Comments

We don’t all need super high quality electronic testing gear. Sometimes second-hand or inexpensive equipment is accurate enough to get the job done. Though it can be a bit annoying to miss out on some of those “luxury” features. [Ekriirke] had this problem with his cheap multimeter. He wished the LCD screen had a backlight for easier visibility, so rather than upgrade to a more expensive unit he just added one himself.

After opening up the multimeter [Ekriirke] found that it ran on a single 12V battery. He realized that the simplest thing to do would be to wire up four white LEDs in series. The four LEDs were arranged within the case off to each side of the LCD, one in each corner. The leads were bent at 90 degree angles and soldered together “dead bug” style. Thin strips of copper foil tape were attached to the PCB in such a way that the anode and cathode from the LEDs would make contact when the case was closed back up.

The tape wraps around to the other side of the PCB where there was more room for the next piece of the circuit. A capacitor, resistor, and transistor are used in conjunction with a momentary switch. This circuit allows [Ekriirke] to turn on the light for about ten seconds by pressing the button one time. The circuit also runs through the meter’s dial switch, preventing the LEDs from being turned on while the meter itself is turned off.

[via Reddit]

LED Sign Brightens Up The Beach After Dark

June 6, 2015 by Rick Osgood 3 Comments

[Warrior_Rocker’s] family bought a fancy new sign for their beach house. The sign has the word “BEACH” spelled vertically. It originally came with blue LEDs to light up each letter. The problem was that the LEDs had a narrow beam that would blind people on the other side of the room. Also, there was no way to change the color of the LEDs, which would increase the fun factor. That’s why [Warrior] decided to upgrade the sign with multi-colored LEDs.

After removing the cardboard backing of the sign, [Warrior] removed the original LEDs by gently tapping on a stick with a hammer. He decided to use WS2811 LED pixels to replace the original LEDs. These pixel modules support multiple colors and are individually addressable. This would allow for a wide variety of colors and animations. The pixels came covered in a weatherproof resin material. [Warrior] baked the resin with a heat gun until it became brittle. He was then able to remove it entirely using some pliers and a utility knife. Finally, the pixels were held in place with some hot glue.

Rather then build a remote control from scratch, [Warrior] found a compatible RF remote under ten dollars. The LED controller was removed from its housing and soldered to the string of LEDs. It was then hot glued to a piece of cardboard and placed into the sign’s original battery compartment. Check out the video below for a demonstration. Continue reading “LED Sign Brightens Up The Beach After Dark” →

Absolute Overkill IKEA Lampan Lamp Hack

May 24, 2015 by Elliot Williams 5 Comments

Sometimes too much overkill isn’t enough. [Jesus Echavarria] hacked an IKEA Lampan light for his daughter to add color LEDs, a timer, Bluetooth control over the hue, and a local override knob. The result: a $5 lamp with at least $50 of added awesomeness. Let’s have a look at the latter.

The whole lamp system is based around a PIC microcontroller and WS2811 LEDs for the color light show. Since the lamp was already built to run a 40W lightbulb, and [Jesus] wanted to retain that functionality, he added an SSR to the build. Yeah, it’s rated for 5,000W, but it’s what he had on hand.

Next comes the low-voltage power supply. [Jesus] needed 5V for the PIC, and used the guts from a cheap USB charger as a quick and dirty 5V converter — a nice hack. To power the HC-05 Bluetooth module, which requires 3.3V, he wired up a low-dropout voltage regulator to the 5V line. A level-converter IC (74LVC07) gets the logic voltage levels straight between the two.

A fuse for the high-voltage power line, screw-terminal connectors all around, and a potentiometer for manual override round out the hardware build.

On the software side, [Jesus] set up the knob to turn on and off the built-in lamp as well as control the colors of the LED ring. That’s a nice touch for when his daughter wants to change the lamp’s color, but doesn’t want to go find her cellphone. But when she does, the SPP Pro app sets the colors by sending pre-programmed serial commands over Bluetooth to the PIC in the lamp.

All in all, a nice build, well-documented, and with enough rough edges that none of you out there can say it’s not a hack. Nice job [Jesus]! We can’t wait to see what he does next… robot lamp anyone?

Build A 100W LED Flashlight

May 21, 2015 by Brian Benchoff 58 Comments

In case you’re not aware, you can hop on your favorite online Chinese electronics retailer and buy a hundred Watt LED module for less than $10 USD. That’s an enormous amount of retina-burning fun, but how do you turn it into a flashlight? DIY Perks shows you how.

The main issue when dealing with these large LED modules is heat. Even though there’s many times more efficient than incandescent bulbs per Watt, that’s still an incredible amount of heat that needs to be removed. There’s a piece of equipment you might have sitting around that does just that: the lowly CPU cooler.

If the CPU heatsink and fan are big enough, the LED module can be attached right to the bottom. With a DC to DC boost converter modified so the entire flashlight can be powered from a LiPo cell, this unit is completely portable, ready to take camping, or even for some very interesting videography.

Continue reading “Build A 100W LED Flashlight” →

“Bricking” Microcontrollers In LEGO Motivates Young Programmers

May 19, 2015 by Bryan Cockfield 15 Comments

Back when he was about seven years old, [Ytai] learned to program on an Atari 800XL. Now he has a seven-year-old of his own and wants to spark his interest in programming, so he created these programmable LEGO bricks with tiny embedded microcontrollers. This is probably one of the few times that “bricking” a microcontroller is a good thing!

The core of the project is the Espruino Pico microcontroller which has the interesting feature of running a Java stack in a very tiny package. The Blocky IDE is very simple as well, and doesn’t bog users down in syntax (which can be discouraging to new programmers, especially when they’re not even a decade old). The bricks that [Ytai] made include a servo motor with bricks on the body and the arm, some LEDs integrated into Technic bricks, and a few pushbutton bricks.

We always like seeing projects that are geared at getting kids interested in creating, programming, and hacking, and this certainly does that! [Ytai] has plans for a few more LEGO-based projects to help keep his kid interested in programming as well, and we look forward to seeing those! If you’re looking for other ways to spark the curiosity of the youths, be sure to check out the Microbot, or if you know some teens that need some direction, perhaps these battlebots are more your style.

Articulated Computer Lamp Lights Up Your Life

May 17, 2015 by Adam Fabio 17 Comments

[Samimy] raided his parts bin to build this articulated lamp (YouTube link) for his computer workstation. Two pieces of aluminum angle form the main body of the lamp. Several brackets are used to form two hinges which allow the lamp to be positioned above [Samimy’s] monitor. The light in this case comes from a pair of 4 watt LED bulbs.

[Samimy] used double nuts on the moving parts to make sure nothing comes loose. The outer nuts are acorns, which ensure no one will get cut on an exposed bit of threaded rod. [Samimy] wired the two bulbs up in a proper parallel mains circuit. The switch is a simple toggle mounted in a piece of Plexiglass on the end of the lamp.

One thing we would like to see on this build is a ground wire. With all that exposed aluminum and steel, one loose connection or worn bit of insulation could make the entire lamp body live.

Continue reading “Articulated Computer Lamp Lights Up Your Life” →

Incredibly Simple Stage For Product Photos

May 15, 2015 by Rick Osgood 18 Comments

If you’ve ever tried to take nice photos of small objects in your home, you might have found that it can be more difficult than it seems. One way to really boost the quality of your photos is to get proper lighting with a good background. The problem is setting up a stage for photos can be expensive and time-consuming. [Spafouxx] shows that you don’t need to sink a lot of money or energy into a setup to get some high quality photos.

His lighting setup is very simple. Two wooden frames are built from scraps of wood. The frames stand upright and have two LED strips mounted horizontally. The LEDs face inwards toward the object of the photos. The light is diffused using ordinary parchment paper that you might use when baking.

The frames are angled to face the backdrop. In this case, the backdrop is made of a piece of A4 printer paper propped up against a plastic drink bottle. The paper is curved in such a way to prevent shadows. For being so simple, the example photo shows how clean the images look in the end.