8-bit Binary Calculator

September 16, 2009 by Mike Szczys 41 Comments

binary_calculator

Don’t feel like shelling out $5 for a fancy factory made calculator that won’t even do binary math? [Jeff] decided to prove his mastery of gates and his disdain for base 10 by building a binary calculator using XOR, AND, and OR chips. Calculations can be input in two ways: through digital logic headers or by three banks of DIP switches used to enter the operator and the two operands. Although limited to addition and subtraction, this is a great way to make sure you really understand digital logic. Take a look at the rough design schematics in his album. The design is modular so if you have one of each gate and a few LEDs sitting around you can give this a whirl.

1:35,200 Scale Train Is World’s Smallest

September 15, 2009 by Phil Burgess 33 Comments

nanotrain

This train layout is so small it nearly defies photography as much as it defies expectations. Built by model railroad enthusiast [David Smith], this is a model of a model: an N scale (1:160) layout inside a Z scale (1:220) world! For size reference, the entire layout is shown under a ballpoint pen tip in the photo above. And it actually runs!

Of course with this being Hack a Day you know there’s going to be some shenanigans involved. Pause the hi-def YouTube video at the 0:50 mark and see if you can puzzle it out first. The remainder of the video and [David’s] project page reveal how this all works, and it’s no less amazing even with the trick exposed. Check out his other ludicrously small mechanical wonders as well!

[via RetroThing]

Color Changing Paint Display

September 15, 2009 by Mike Szczys 47 Comments

heat_actuated_display

We’ve seen several creative projects from [Sprite_tm] and this one sets a new bar. He got his hands on some paint that changes color with temperature. By covering a circuit board with the paint then heating the circuits he’s created a heat actuated 7-segment display (his post is in Dutch). Three seconds at about 1 amp is enough to turn the black paint white. When the segment has been disconnected for about one minute the paint fades back to black. Now that we’ve seen his concept, leave a comment and tell us how you’d use it.

Dual Voltage Power Supply

September 14, 2009 by Mike Szczys 29 Comments

dual_regualted_power

[Melanie] had some time this weekend so she whipped up a dual voltage power supply from parts on hand. This design plugs right into a breadboard and, unlike the last breadboard power supply we saw, provides two voltages at one time. 5v is delivered to one power bus while 3.3v goes to the other. Her design uses two linear low voltage drop regulators from the LF00 family (PDF datasheet) to accomplish this. Nice work!

Beer Brewer’s Temperature Controller

September 13, 2009 by Mike Szczys 12 Comments

freezer_temperature_controller

Steady fermentation temperatures, usually at about 65 degrees Fahrenheit, are an important part of brewing beer. Because of this, the wort (unfermented beer) is often temperature controlled during fermentation. [android] needed a temperature controller for fermenting beer in a chest freezer. Much like the energy efficient fridge hack from last month, the chest freezer is switched on and off to achieve the desired temperature. Instead of buying a controller, [android] built around an existing design. His project uses a solid state relay to switch an outlet on and off.

The temperature is controlled by a home thermostat. He removed the thermistor from the unit and extended it with 24 gauge wire so that it can go inside of the chest freezer. Utilizing a junction box, the freezer is plugged into one switched outlet and controlled by the thermostat via the relay. The other outlet is unswitched and provides DC power for the relay using a wall wort transformer. Although this thermostat cannot be set cold enough for lagering, it is perfect for keeping kegs at the correct beer serving temperatures when not being used for fermentation.

Dot Matrix Clock On The Way

September 12, 2009 by Jakob Griffith 25 Comments

[Kevin] sent in his almost finished open source dot matrix clock. Sporting a hefty 40 x 16 display powered by a PIC 18F he has complete pixel by pixel control of the graphics. Combined with with a triple buffer he is at least able to output 15fps, with planned 30fps. While this has great potential for a clock, what about going further? Twitter updates, chat messages, weather updates, the current airspeed velocity of an unladen swallow; it will be tough to beat the competition without some more features. Either way, its an awesome project and we can’t wait to see it completed.

Exoskeleton Rental Now Available

September 11, 2009 by Mike Szczys 31 Comments

[youtube=http://www.youtube.com/watch?v=B_k30yeCk4c]

The HAL two-leg exoskeleton is now available for rent in Tokyo for $2300 per month. We saw the HAL in our power suit roundup from last year. There is footage of this lower-extremity suit demonstrated by three people. The video is a bit creepy because the they are apparently just out for a stroll in the city.

We really do want to see this succeed. Every time another advancement in exoskeletons comes around we glimpse the future of mobility and freedom for victims of paralysis. The machine is controlled via an interface that picks up electrical impulses on the surface of the skin. The built in battery provides power for up to five hours of operation before recharging is necessary.

[Thanks David]