VoIPing the iPod Touch

VoIPing the iPod Touch
How makers gave you the feature that Apple held back
Erica Sadun | Make Vol. 15- 2008 | Pdf | 2 pgs | 1 mb

It's a maker's dream: turn your homebrew ideas
into a concrete reality and then ship that product.
This dream came true for iPod hackers Dr. Marian
Kepesi, "Eok," and Samuel Vinson. They designed,
built, and shipped an iPod touch microphone and
developed VolP(voice over internet protocol) soft-
ware to place phone calls using that mic.

Last November, Kepesi was poking around on his
iPod Touch. A postdoc at Austria's Graz University
of Technology, he had previously worked with third-
generation iPods and was interested in the new
Touch line.

During his explorations, he discovered an impor-
tant fact about the iPod Touch's bottom connector
port: its line-in audio was active. Live pins meant
that the iPod Touch could connect to an external
audio source. It was compatible with recording or,
better yet, with VolP for talking over the internet.
VoIP compatibility was a long-standing goal of the
iPhone and iPod Touch hacker community.
...

Download...
Mirror

The Penetrating Magnets Illusion

The Penetrating Magnets Illusion

"Magnets are fascinating things, and they behave in
unexpected ways. I will show you a little-known
property of magnets, which actually allows them to
pass through one another."
Donald Simanek | Make Vol. 15- 2008 | Pdf | 2 pgs | 1 mb

Back in 2004, I invented a physics toy using
magnets, one I hadn't seen described elsewhere.
So I called it Simanek's Penetrating Magnet Illusion.
It obeys Newton's laws, like the others, but why
should Newton get all the credit?

This toy is inexpensive and absurdly easy to build.
Find a dozen small, flat ceramic magnets, 1" diameter,
1/4" thick, with a 3/8" hole in the center. You can get
them at RadioShack or hardware stores. You don't
need a full dozen, but extras are good to have.
...

Download...
Mirror

Great Balls of Fire!

Great Balls of Fire!
Keith Hammond | Make Vol. 16- 2008 | Pdf | 5 pgs | 2 mb

It's true: chemistry sets today don't measure up
to the classic kits that once scorched Formica
kitchen tables across the nation. But you can
still find respectable kits if you know where to look.
More importantly, anyone can make their own flam-
ing, fuming, booming DIY chemistry set as good as
those from the golden age - or better.

Download...
Mirror

The Amazing Seebeck Generator

The Amazing Seebeck Generator
Andrew Lewis | Make Vol. 15- 2008 | Pdf | 9 pgs | 3 mb

FLAME ON
With no moving parts, this simple energy-recycling
generator scavenges waste heat from a candle and turns
it into usable electricity.

Peltier cells are flat devices that draw heat from one side
to the other through a thermoelectric principle called the
Peltier effect. The cells are commonly used to pump heat
away from CPUs or graphics cards, and are also found
in camping coolers and heaters. The Amazing Seebeck
Generator uses one of these devices in reverse, to turn a
heat differential into electricity, rather than using electricity to produce a heat differential.
...

Download...
Mirror

Compressed Air Rocket

Compressed Air Rocket
Rick Schertle | Make Vol. 15- 2008 | Pdf | 13 pgs | 4 mb

PAPER, TAPE, COMPRESSED AIR... LIFT-OFF!
Blow your friends away as you send this 25-cent
rocket hundreds of feet in the air. You can build this
easy launcher and rocket with common hardware store
items in an afternoon.

All the parts for this simple but impressive air rocket and
launcher are cheap and easy to find. Building it is a breeze
and the modifications are endless. It's legal in a big city,
reusable, clean, and can be launched even in high winds
on a small field.

Believe me, folks are quite taken by the 200- to 300-foot
flights fueled by 18 or so bicycle pumps of compressed air.
Whether you're launching on your own or with a whole
group of rocketeers, watch the crowds gather ... 3,2,1,
and away!

Download...
Mirror