Timofte Andrei wrote this instructable detailing the build of his Arduino home automation system:
For this project I’ve used:
1. An Arduino clone
2. SIM900 GSM SHIELD
3. Relay module
4. 2×16 LCD Display
5. DS18B20 temperature sensor
6. Push button
7. Some Dupont wires
8. A led module (this is optional, if you have a chinese relay module with built in LEDs)
9. Some nuts and bolts to mount everything in place
10. A wooden chopping board or other kind of wooden board for propper display of the components
Arduino GSM home automation system - [Link]
Get to know the Shunt and Series selection guide parameters to choose the right Vref for your application.
Voltage Reference Overview - [Link]
Kepler is a multi-function device that monitors gas and carbon monoxide levels in your home, and delivers life-saving warnings. It features active gas and CO monitoring, early warning, a portable design, and a gesture-controlled kitchen timer in a sleek, modern body.
Kepler Team created Kepler because gas leaks are really dangerous, and they want to help prevent natural gas tragedies.
Kepler is an intelligent gas and carbon monoxide detector that features active monitoring, intelligent alarms, portable design and more
Kepler: Your Best Home Gas Detector - [Link]
Desoldering braid makes an invaluable service at development or rework.
Everyone who´s ever tried to suck off a solder from a solder pad by means of a solder absorbing braid (wick) will probably confirm, that this tool belongs to a “must have” equipment of every professional or amateur workplace. What´s the charm of a desoldering braid? Above all in the fact, that it´s able to absorb almost all the solder from a given place, thus the most of components can be loosened very easily. Hand (pneumatic) pump surely has its place, mainly when working with bigger components, but at comparison with a desoldering braid it´s similar like if we compared a broom with a vacuum cleaner.
A quality desoldering braid is usually able to absorb a solder so thoroughly, that only a microscopic layer of a solder will remain on a PCB – as if a board was new, unused. It is very advantageous even at a hand rework of SMT components, because it´s desirable the component to lay directly on a board – not askew in a thick solder layer causing a mechanical tension and able to cause even a malfunction of a component (often at SMT capacitors).
To reach a good functionality of a desoldering wick it should be made of a fine gauge copper wires (without oil residues end similar) and it must be treated with a high quality flux. The cheapest braids usually contain only a rosin-based flux, the better ones have a synthetic flux based, which produce less fumes.
A novelty in our portfolio is the novelty from company CRC Industries – braid SOLDABSORB. We keep Soldabsorb in a width of 1.5 and 2.5mm, packed in a blister in 2 pcs (the price is for 2 pcs). Soldabsorb represents a top-level in this segment and is made of a highly pure copper, fine gauge wires and contains a synthetic NO-CLEAN flux. It means, that the flux residues are non-conductive and non-corrosive and they can be left on a PCB. Very fine wires contribute to a high wicking (absorbing) ability.
The usage of the wick is very simple and is based in 4 steps:
● Place the Soldabsorb wick on the solder joint
● place the tip of the solder iron on the wick and hold shortly
● absorbed solder will change a color of a braid, showing that the process was successful
● when a joint contains a big amount of solder, it may be necessary to cut off a used end of a braid (2-5mm) and repeat the process
In praxis it approves well to adjust temperature of a soldering iron to a slightly higher, than we´d normally need for a given pad and eventually also to use a thicker soldering tip. In especially difficult cases (vias at ground planes of a PCB) it helps to put a small amount of a new solder on a soldering tip, which will decrease an absorbing ability of a braid, it will significantly improve a heat transfer from a tip through a braid to a PCB, thus improving and speeding up an absorption. Before another use of a braid, it´s sufficient to cut off only a very end of a braid (a few mm) fully sucked by a solder.
At the end it´s worth to mention, that after desoldering, it´s good to apply a small amount of solder on a soldering tip to protect it from oxidizing.
Detailed information will provide you the Soldabsorb datasheet.
Desolder professionally with NO-CLEAN flux wicks - [Link]
Water Level Alarm is a simple project to detect and alarm once the water level in tank or Aquarium reaches at certain level. Circuit is based on popular NPN transistor BC547 which act as switch, Sensor also made on PCB, when the water reaches the sensor PCB, base of transistor connected to positive supply, in consequence transistor act as switch and activate the buzzer.
Water Level Alarm - [Link]
My first attempt at an LED Aquarium light started as an excuse to buy some of those LED light strips off of eBay. I gutted the old 18″ fluorescent fixtures and soldered together row after row of 18″ RGB LED strips. They mounted to a thin aluminum plate I screwed into the old light housings. I mounted one of those remote-controlled RGB LED controllers in there with a 12V 5A power brick. The remote control let us change the colors, and had a few blinky light modes that I’m sure the fish didn’t appreciate too much. My wife loved it, which is all that really matters.
Aquarium Light V1 - [Link]
by Martin @ harizanov.com:
I purchased a battery operated smoke/fire alarm few days ago and it showed up today. It runs on 9V and will make a loud sound if smoke is detected. My intention was to hook it up with my home automation system so that I would receive alert if it would go off including SMS, pushbullet notification to my phone, email etc.
The Funky v1 is ideal for the purpose because it is really flat/tiny and would fit inside the alarm. It will tap into the piezo siren and sleep until the siren is activated. Upon activation, it will make a wireless transmission to my home automation system (Raspberry Pi running Node-Red) for further processing and alerting me on my phone.
DIY Internet of Things Fire Alarm - [Link]
Electronics DIY published a new build, the Curious C-beeper:
Curious C-Beeper is a fun to build little probe that can be used to quickly detect the capacity of capacitors in pF nF range, test their stability with temperature changes, find broken wires, locate wires, trace wires on PCBs, and to locate live wires behind the walls without touching them. The circuit uses three transistors to make a most unusual capacitance beeper probe. When a capacitor is touched to the probe, the probe beeps at a frequency that varies with capacitance. The frequency change is so steep with capacitance that tiny capacitors may be precisely matched or an exact fixed value may be selected to replace a trimmer in a prototype.
Curious C-beeper - [Link]
An interesting open source NFC project is seeking for funding on kickstarter.
MicroNFCBoard is an integrated development platform that makes it easy to use Near Field Communication or NFC (What is NFC? see below for more info). It contains a NFC transceiver, a microcontroller and all the software you need to use NFC.
It can be used with an Arduino, Raspberry Pi, mbed or PC/Mac. There is also a powerful ARM Cortex-M0 microcontroller onboard so it can work on its own and you can connect a bunch of things to the board using its various peripherals.
MicroNFCBoard – Easy NFC for the Internet of Things - [Link]