In this article I describe the simple setup and explain the code to drive analog meters using PWM outputs from an Arduino and the LCD Smartie program. I also replace the meter face to show the proper scale. Replacing the meter scale is very easy to do with most meters and can really ad some style to your project.
Arduino Analog Gauge - [Link]
Here’s a how-to on building a low cost vehicle tracker using the Telit GM862-GPS module. The GM862-GPS is a hardware module that supports connections on local GSM networks as well as GPS signals. In addition, this device supports a Python interpreter which allows for easy interfacing to build a simple tracker. Lots of info at the below link. [via]
Build a vehicle tracker on the cheap - [Link]
Here is how to make an LED brake light for your motorcycle. It doesn’t have detailed schematics, but there is a nice photo gallery of the build process. There are several advantages to using LED’s according to the author:
- Instant-on – There is no filament to heat up, so the light comes on immediately. This should attract others drivers’ attention.
- Uniform brightness – By using 80 LEDs, I can fill the taillight evenly with light, thereby making the most of the limited area I’ve got.
- Higher brightness – I can make the brake light brighter than stock.
- Lower power – At maximum brightness (which I won’t use), this light takes 20 Watts — less than the 35 Watts the normal taillight takes. [via]
LED Motorcycle Tail Light - [Link]
Finkbuilt has very detailed instructions on building a one-shot 555 timer. The article is full of diagrams and pictures of the circuit building process. This is a great read for anyone interested in the famous 555 timer. [via]
One shot 555 timer - [Link]
What’s the perfect gift for the special someone that puts up with a soldering iron in the kitchen and little bits of wire underfoot? How about this touch activated, pulsating LED heart? This geeky Valentine’s Day card pays homage to the musical greeting cards that are popular this time of year. This isn’t just for Valentine’s Day — it’s a simple heart, so give it to your loved one any time of the year. You can also make your own shapes using the same basic circuit. [via]
Touch activated LED valentine - [Link]
Daenris writes -
This project uses an RF receiver module to trigger a pulsing LED Heart when the transmitter comes within range. I made this for my fiance for Valentine’s Day this year.
I have yet to fully test the range, as I haven’t actually taken the transmitter out of our apartment building since I just finished it today. The transmitter/receiver pair that I used is hypothetically capable of up to 500 feet, though that is the open space line of sight range. I haven’t yet added antennas to either the receiver or transmitter box, but that should hypothetically improve the current range. [via]
Make a pulsing hubby detector – [Link]
Wouldnt it be sweet if you could have your micro play-back complex things, over audio for an extremely low cost? Imagine replacing that one i/o line that used to drive an led, be able to reproduce the human voice and exclaim “Hello world”, This can be useful in projects where you would like to add some human interface, but an lcd would be too bulky / to slow.
PWM audio generation with an AVR - [Link]
found on popsci.com:
Bring a dead electric screwdriver back to life in seconds by adding quick-charging super capacitors. It’s the do-It-yourselfer’s version of Murphy’s Law: Every time you need to sink some tough screws, the battery in your cordless screwdriver is dead. So you do the only thing you can … [continues]
Make an Instant-Charge Screwdriver - [Link]
We used to see dual supply ideal operational amplifiers (Op Amps), what means that Op Amps are powered from dual supplies with equal magnitude and opposing polarity. The center tap is connected to the ground which serves as a center of the supply voltage.
Single supply operational amplifiers are powered with single polarity voltage. In this case you loose convenient ground reference that split supply op amps have. In this case you must ensure that signal swings between correct voltages (eg. VCC and GND) …
Single supply operation amplifiers versus dual supply - [Link]
Measuring device is combined of mini application module with Atmega128 microcontroller and two SFR04 sonic modules. Measuring principle is very simple. Measure time between sonic transmission and echo reception and then divide it by sound speed in this environment. Timing is explained in this diagram.
Calculated distance is displayed on LCD screen. Sonic distance meter can measure distances from 3cm up to 3 meters and can reflect form 3 cm obstacles at 2 meter distance. I would say quite good addition to some robotic platform. Source codes are written for AVR-GCC compiler and can be downloaded form site. [via]
Measuring distances with SRF04 sonic module - [Link]