A homemade thermostat up in the basement rafters controls the heating in my home. The smart bit is the radio frequency communication that connects it to a remote temperature sensor.
This compact PCB interfaces a low power MSP430G2553 microcontroller with a Nordic NRF24L01+ 2.4 GHz radio frequency transceiver module. It's well adapted to serve as a wireless sensor node, but has enough I/O options to be put to use wherever a small microcontroller is required. PCBs now available from Tindie!
I have a MacBook Air with an Intel i7 core running OS X Lion 10.7.5. Booting linux from a flash drive was not straightforward, to the point that when I finally got it working I laughed with surprise. Evidently doing such things is not part of the one true Apple way. The instructions were cobbled together from from here and here with a fair bit of trial and error. Needless to say, the procedures documented on the Ubuntu website did not work for me.
A digital stirring hotplate in decent used condition will set you back about $250. I paid a fraction of that for one with a broken heating function. The problem turned out to be nothing more than a duff switch.
When I ordered some NRF24L01+ boosterpacks from the 43oh store, I asked for a couple of MSP430 Launchpad v1.4 PCBs. These are legacy boards kindly provided by TI (thanks LariSan!) It was fiddly soldering to the tiny 0402 pads since my components were all 0805. The LEDs were especially tricky. But they both turned out OK as you can see. Here they are (alongside a genuine Launchpad on the left) running the breathing LED demo from the OSX Launchpad toolchain.
Exercise bike + magnets + LEDs = festival of light. Devised by T.J.Hunt with specialist engineering expertise from Rabbi Shena Potter Jaffee. Come along 3rd December to the Mayerson Jewish Center of Cincinnati. Pop a beer, grab a latke, and take a spin. Happy Hannukah!
Last week I won the weekly trivia quiz from Tier1Automation, and came dead last in the 43oh Halloween competition with my Jack-O'-Launchpad — but still won the booby prize of 2 MSP430 Launchpad v1.4 PCBs. The freebies arrived in the same post. Good times!
The diagram shows how to connect an Adafruit MAX31855 breakout board to the stripboard Arduino PID shield. Vin should connect to the 5V pin and DO, CS, and CLK to A0, A1, and A2 respectively. Connect a K thermocouple in the screw terminals. If the temperature reading goes down when it should go up, switch the thermocouple wires around.
The graphical user interface allows every feature of the Arduino PID controller shield to be governed remotely via the serial interface. A powerful additional feature is the ability to set multi-stage temperature profiles for applications where the set point changes over time.
Perhaps not the most imaginative used of a Tiva Launchpad, but the default application makes for a serviceable Jack-O'-Lantern. Powered by a USB adapter from CUI, a freebie via @digikey on twitter. Nice!
What we have here. A battery holder, 2 tactile switches, 4 LEDs, and a chip with a blob on that makes a crappy noise. I don't even want to know how the plastic shaft got broken but no ambulances were called. Nothing to salvage or Halloweenify. Let's move on.
This cheap dimmer is designed to blink LEDs with a variable duty cycle. The default frequency can be altered by swapping out a single capacitor. 20 kHz makes a whine-free speed control for a DC motor, 1 Hz gives slow PWM for high power resistive heating loads.
LED voltmeters are a cheap source of 7 segment displays and can easily be repurposed. Using the I2C protocol, a master microcontroller such as an Arduino Uno can govern multiple displays with just 2 I/O pins.
While on vacation I impulsively bought fertile chicken eggs from a farm stall. Needing to incubate them immediately, I cobbled together a rudimentary incubator from a styrofoam cooler and a few bits and pieces. A PID controller was the perfect device to govern the temperature.
Converting an ATX power supply is a great way to get juice to your electronics projects. With the ATX breakout board from Dangerous Prototypes you can do it while waiting for your toast to pop up, and it looks pretty good too.
I wanted a low table on which to set up my brewing gear. It would need to support a couple of hundred kilos and fold flat to the garage wall. Failure could send 100 litres of hot liquid and a variety of electrical power equipment crashing to the floor. Neanderthal design principles seemed appropriate to my levels of sophistication and skill, so I hacked together this clunky hinged table top.
In which I buy an old school welder off the friendly neighbourhood chopper freak, fix it up, make an illuminated foot switch for it (which works although I have no idea how), and start gluing things together with hot metal, badly. Like warty Oscar here.
Thanks to TE Connectivity for their promotion via the Digikey twitter feed. My laptop fits in the backpack perfectly - just right for cycling. I was doubly surprised when Digikey sent me another the next day. But then, I like coordinated luggage. The third one is in the mail, right? ;-)
Yours Truly (@YT2095) is putting together a Magic Mouth v1.0 speech synthesis shield for his Saturday morning project! Just for fun, I sent him one the PCBs I had got back from Seeedstudio's FusionPCB service. He's substituted a potentiometer for the thumbwheel trimmer, and it looks like one last header and the jack socket still need to make it onto the board. It's looking good, John. :)
So if you open up a 9 V battery, you find 6 thin 1.5 V cells inside. But what was inside that lantern battery, the rechargeable PP3, or the funny shaped lump on the back of my laptop? Confronted with dead metal in the recycling drawer, I tried to find uses for the contents.