The Spindicator

September 3, 2010 by Caleb Kraft 39 Comments

oooh shiny

[Harvey] wrote in to share the Spindicator with us. The spindicator is a hard drive activity activity indicator built in a ring to resemble a dekatron. Using the pulses from the hard drive activity LED, [Harvey] tested several different methods of interpreting that data for display. The final version, negative edge triggered with a lowpass filter can be seen after the break. It is nice and smooth and vaguely reminiscent of many programs’ loading screens.

He has pictures and tons of detail on the project including videos of previous versions that acted quite erratically.

Continue reading “The Spindicator” →

Motorcycle Current Gear Indicator

June 4, 2010 by Mike Szczys 42 Comments

[Vassilis Papanikolaou] just finished building a gear indicator for a motorcycle. This quite a simple implementation compared to some of the other vehicle information displays we’ve taken a look at. You should be able to build and install your own without breaking the bank. An ATtiny25 microcontroller reads data from a couple of hall effect sensors and the neutral switch, then displays the current gear on a 7-segment display.

There’s a magnet on the shifter and two hall effect sensors at the position for ‘gear up’ and ‘gear down’ shifting. The AVR chip keeps track of these and even stores the last position in EEPROM when you shut the bike off. If the device somehow gets off track, it will automatically recalibrate itself next time you shift into neutral, thanks to the bike’s neutral sensor switch.

Open Garage Door Indicator

September 26, 2009 by Jakob Griffith 49 Comments

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How many times has this one happened to you? Just coming home from work, you walk in from the garage, settle down, and pick up the newspaper. But wait, did you remember to shut the garage door?

Presenting the open garage door indicator. [xjc2010] chose the simplest circuit possible, using only a switch to turn on and off the setup, an LED acting as the signal, and a transformer/resistor combo to drop the voltage to an acceptable LED friendly 2.8 volts. We don’t like how he strung wire all over his house to place the beacon, and would have preferred something wireless in one way or another, but for under 6 bucks this gets the job done quickly and cheaply. Now if only we could get it to remind us if we turned off the oven while on vacation.

[thanks Craig]

LED Battery Level Indicator

July 3, 2008 by Juan Aguilar 16 Comments

[Kc7fys] came up with a this simple battery level indicator. It uses a single LED to display a battery’s voltage; if the voltage exceeds 12V, it glows green. If it is below 11V, the LED glows red. Anything in between generates an orange glow. The meter is built around an LM358 chip per this schematic, but his actual build looks pretty sloppy because of the dead-bug assembly (check out NASA’s pretty version). Nonetheless, it works, so clean it up and build one if you want to put it (or your batteries) to the test.