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.
[Matt] was looking for a project for his senior industrial design studio at Wentworth Institute of Technology. He ended up designing a clever lamp that can be flat packed. [Matt] started by drawing out designs on paper. He really liked the idea of combining curves with straight lines, but he wanted to translate his two-dimensional drawings into a three-dimensional shape.
Having access to a laser cutter made the job much easier than it could have been and allowed [Matt] to go through many designs for the lamp frame. The two main pieces were cut from acrylic and include mounting pegs for the elastic bands. The two plastic pieces are designed to slot together, forming a sort of diamond shape.
The final version of the lamp required that the elastic bands had holes punched in them for mounting. The holes were placed over the small pegs to keep the bands in place. [Matt] used 3/4″ industrial elastic bands for this project. He then used a 120V 15W candelabra light bulb to illuminate the lamp. The final design is not only beautiful, but it can be flat packed and manufactured inexpensively.
If you want more inspiration for artistically designed lamps check out this one that uses the corrugation in cardboards as a shade pattern.
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.
WARNNG: Walking around in the dark could be dangerous to your health! You may bump into something or worse, take a tumble down the stairs. Safety conscious [Ganesh] has come up with a solution for us folks too lazy to manually turn on a light. It’s a simple light controlled by a motion sensor that anyone can put together.
The meat and potatoes of the build is an off-the-shelf motion sensor, the same kind that is used in a home security system. We humans emit infrared energy and that is just what this sensor ‘sees’. The motion sensor is powered by 12 VDC and has a pair of DC output leads that are used to control a relay. [Ganesh] used an standard hobby relay board with built in power spike protection diode and transistor to supply the current required to trip the relay. Closing the relay sends mains power to the AC light bulb. Both the triggering threshold and the ‘on’ time are controlled by potentiometers integrated with the motion sensor.
Check the video out after the break of the device working its magic and lighting the way to [Ganesh’s] basement dungeon…
Continue reading “Motion Light In Dark Stairwell Brightens Trips To The Basement”
If you are into your social media, then you probably like to stay updated with your notifications. [Gamaral] feels this way but he wasn’t happy with the standard way of checking the website or waiting for his phone to alert him. He wanted something a little more flashy. Something like a flux capacitor notification light. This device won’t send his messages back in time, but it does look cool.
He started with an off-the-shelf flux capacitor USB charger. Normally this device just looks cool when charging your USB devices. [Gamaral] wanted to give himself more control of it. He started by opening up the case and replacing a single surface mount resistor. The replacement component is actually a 3.3V regulator that happens to be a similar form factor as the original resistor. This regulator can now provide steady power to the device itself, as well as a ESP8266 module.
The ESP8266 module has built-in WiFi capabilities for a low price. The board itself is also quite small, making it suitable for this project. [Gamaral] used just two GPIO pins. The first one toggles the flux circuit on and off, and the second keeps track of the current state of the circuit. To actually trigger the change, [gamaral] just connects to the module via TCP and issues a “TIME CIRCUIT ON/OFF” command. The simplicity makes the unit more versatile because an application running on a PC can actually track various social media and flash the unit accordingly.
For the past month, the Raspberry Pi 2 has only been available to the Raspi Foundation, and for about 2 weeks, select members of the media who have worn the Raspi 2 on a necklace like [Flavor Flav] wears a clock. That’s not many people with real, working hardware and when a product is released, the great unwashed masses will find some really, really weird bugs. The first one to crop up is a light-sensitive reset of the Raspberry Pi 2.
[PeterO] on the Raspberry Pi forums took a few pictures – with flash – of a running Raspberry Pi 2. It took a little bit of deduction to realize that a camera flash will either reset or turn the Raspi 2 off. Yes, this is weird, and experiments are ongoing.
A short video from [Mike Redrobe] confirms the finding and a reddit thread offers an explanation. U16, a small chip located in the power supply part of the Raspi 2, is sensitive to light. Putting enough photons will cause the Pi to shut down or restart.
There’s still some research to be done, however, I can confirm a cheap green laser pointer will reset a Raspberry Pi 2 when the beam is directed at the U16 chip. This is the chip that is responsible, and this is not an EMP issue. This is a photon/light issue with the U16 chip. The solution to this bug is to either keep it in a case, or put a tiny amount of electrical tape over the chip.
Thanks [Arko] for staying up until an ungodly hour and sending this to me.
If you are like [Gbola], then you have a hard time waking up during the winter months. Something about the fact that it’s still dark outside just makes it that much more difficult to get out of bed. [Gbola] decided to build his own solution to this problem, by gradually waking himself up with an electric light. He was able to do this using all off-the-shelf components and a bit of playing around with the Tasker Android application.
[Gbola] started out with a standard desk lamp. He replaced the light bulb with a larger bulb that simulates the color temperature of natural daylight. He then switched the lamp on and plugged it into a WeMo power switch module. A WeMo is a commercial product that attempts to make home automation accessible for consumers. This particular module allows [Gbola] to control the power to his desk lamp using his smart phone.
[Gbola] mentions that the official WeMo Android application is slow and includes no integration with Tasker. He instead decided to use the third-party WeMoWay application, which does include Tasker support. Tasker is a separate Android application that allows you to configure your device to perform a set task or series of tasks based on a context. For example you might turn your phone to silent mode when your GPS signal shows you are at work. WeMoWay allows [Gbola] to interact with his WeMo device based on any parameter he configures.
On top of all of that, [Gbola] also had to install three Tasker plugins. These were AutoAlarm, Taskkill, and WiFi Connect. He then got to work with Tasker. He configured a custom task to identify when the next alarm was configured on the phone. It then sets two custom variables, one for 20 minutes before the alarm (turn on the lamp) and one for 10 minutes after (turn it off).
[Gbola] then built a second task to actually control the lamp. This task first disconnects and reconnects to the WiFi network. [Gbola] found that the WeMoWay application is buggy and this “WiFi reset” helps to make it more reliable. It then kills the WeMoWay app and restarts it. Finally, it executes the command to toggle the state of the lamp. The project page has detailed instructions in case anyone wants to duplicate this. It seems like a relatively painless way to build your own solution for less than the cost of a specialized alarm clock lamp.