Sometimes finding a short-circuit is easy, especially after the magic smoke has escaped. Finding a short on a newly etched or milled board though, can be a maddening task. Many of us have been there – wrestling with multimeter probes under a magnifier trying to find the offending bit of copper that is the source of all our problems. [Jaromir] designed Shorty to make this task a little bit easier.
Shorty is a short-circuit finder – but it’s not exactly like the one you would find on a typical multimeter. [Jaromir] used MCP6041 Op-Amp to detect resistances down to the order of tens of milliohms. Determining an exact resistance measurement at these levels would require a heck of a lot of calibration. When looking for a short though, [Jaromir] is only concerned with the relative value – is he getting closer to or further away from the short. He determines this by sound. The Op-Amp output is sent to the Pro Trinket’s ADC input. The trinket drives a speaker with lower or higher tones based upon the ADC voltage. Much like the childhood game of “hot and cold”, Shorty will direct you right to your short!
There’s still time to enter the Trinket Everyday Carry Contest. The main contest runs until January 2, but we’re having random drawings every week! Don’t forget to write a project log before the next drawing at 9pm EST on Tuesday, December 30th. You and all of the other entrants have a chance to win a Teensy 3.1 from The Hackaday Store!
[Vasilis] has entered Lazydoro in the Trinket Everyday Carry Contest. Lazydoro is designed to get him up off his backside, and walking around. Recent medical research has determined that sitting too long is a bad thing. In fact, Dr. David Agus has been quoted by Nike as saying that sitting for several hours is as bad as smoking (wayback machine link). While we’re not exactly up on the latest medical trends, we can definitely see that getting up and walking around a bit never hurt anyone. Lazydoro will alert [Vasilis] once every 20 minutes or so to get up and stretch his legs a bit.
[Vasilis] plans to pair a Pro Trinket with an accelerometer module, specifically an ADXL377 from Analog Devices. The accelerometer will allow Lazydoro to determine if [Vasilis] has moved around. If 20 or 30 minutes go by without major movement, Lazydoro will nudge him to get up and take a walk.
Since shipping to Greece takes awhile, [Vasilis] is developing with an Arduino Uno and a ADXL345 while he waits for his parts to arrive. He’s hacked this into a wrist mounted device for testing. One thing [Vasilis] hasn’t figured out yet is how to alert the user to move around. A small vibrating motor would probably work – but we’d suggest electric shocks. A good zap always puts the spring in our step!
There is still plenty of time to enter the Trinket Everyday Carry Contest. The main contest runs until January 2, but we’re having random drawings every week! Don’t forget to write a project log before the next drawing at 9pm EDT on Tuesday, December 23. You and all of the other entrants have a chance to win a Cordwood Puzzle from The Hackaday Store!
[BDM] is helping others keep WiFi safe with “Shame On You!“, his entry in Hackaday’s Trinket Everyday Carry Contest. We all have that family member, friend, or neighbor who just can’t seem to get their WiFi locked down. Shame On You will show them how easy it is to detect such a hotspot, which hopefully will motivate them to correct the issue. [BDM] was a bit worried when he learned that Adafriut already has an open WiFi detector as one of their Pro Trinket example projects. However, we think he has added more than enough features to make his project stand out.
Shame On You is using a Pro Trinket running at 3.3 volts, along with an ESP8266 WiFi module. Power comes from a LiPo battery and is handled by an Adafruit LiPo backpack. Like several other EDC contest entries, Shame On You is using a cell phone shell as a case. The display is a 1.27″ color OLED with an SD card. A disc style vibrator motor will also help get the user’s attention.
[BDM] hasn’t made much progress this last week, as he’s been battling some Christmas light cutting bandits. Logging each week’s work doesn’t always have to be technical, sometimes life intervenes!
We’re heading into our third week here in the Trinket Everyday Carry Contest, but there is still plenty of time to enter! The main contest runs until January 2, but we’re having random drawings every week! Don’t forget to write a project log before the next drawing at 9pm EDT on Tuesday, December 16th. You and all of the other entrants have a chance to win a BusPirate 3.6 from The Hackaday Store!
We’re getting all sorts of entries in the Trinket Everyday Carry Contest! Today we’re featuring just a couple of the awesome entries dedicated to creating music!
[johnowhitaker] is hard at work on A Musician’s Assistant. [John] is creating a device that does anything a practicing musician might need on the go. The Musician’s Assistant will include a metronome, tap/temp counter, and tuner. He’s hoping to also give it the ability to play back arbitrary notes using the Pro Trinket’s on-board ATmega328. [John] is trying to do all this with just LEDs and buttons as a user interface, though he is willing to go to an LCD or OLED if he needs to.
[Michele Perla] is working on BitMasher, portable lo-fi music sequencer. The BitMasher will allow a musician on the go to create music anywhere. [Michele] began with a SID based sequencer in mind, but he’s currently trying to do it all on the Pro Trinket. He’s already got [Roman’s] BTc Sound Compression Algorithm working on an Arduino Leonardo. Lo-Fi for sure, but that’s what makes BitMasher fun! [Michele] envisions the song entry to be similar to that of the classic Roland TR-808. The primary user interface will be an Adafruit Trellis 4×4 button+LED driver board.
Don’t forget that our second random drawing will be held on Tuesday, December 9th, at 9pm EST. To be eligible you need to submit your project as an official entry and publish at least one project log during the week. This week’s prize is a Cordwood Puzzle from The Hackaday Store. Check out the contest page for the full details!
[Eric] is well on his way to making one of the less pleasant chores of pet ownership a bit easier with his dog tracking system. The dog tracker is actually a small part of [Eric’s] much larger OpenHAB system, which we featured back in July.
As a dog owner, [Eric] hates searching the yard for his pet’s droppings. He had been planning a system to make this easier, and a local hackerspace event provided just the opportunity to flesh his ideas out. The Dog Tracker’s primary sensor is a GPS. Most dogs remain motionless for a few seconds while they go about their business. [Eric’s] Arduino-frgbased system uses this fact, coupled with a tilt sensor to determine if the family pet has left any presents.
The tracker relays this information to the home base station using a HopeRF RFM69 transceiver. The RFM69 only has about a 900 foot range, so folks with larger properties will probably want to spring for a cellular network based tracking system. Once the droppings have been tracked, OpenHAB has an interface
[Eric] has also covered runaway dogs in his design. If Fido passes a geo-fence, OpenHAB will raise the alarm. A handheld dog tracker with its own RFM69 can be used to chase down dogs on the run. Future plans are to miniaturize the dog tracker such that it will be more comfortable for a dog to wear.
Continue reading “Dog Tracker Knows Where the Dirt is”
Let’s face it, walking around in the rain sucks. [Matth3w] is trying to add a little whimsy to an unpleasant experience by adding an LED matrix to his umbrella. The array contains 80 LEDs that are individually addressable. This is a mutiplexed array that relies on a MIC2981 source driver for the eight rows (or rings in this case), with the ten columns handled by the Arduino. The effect is quite nice as you can see in the video after the break. Now that he’s proven this works, you might want to etch your own PCB in order to get rid of the Arduino board and prototyping shield, making it easier to waterproof the control circuitry. This would make a nice addition to your illuminated umbrella stock.
Continue reading “Putting on a show in the rain”