Building The Shmooball Cannon

shmoo

We’ve been eagerly anticipating this, [Larry] has published the entire build of the Shmooball gun for 2009. This design is more compact and elegant than the one for 2008 and has a slightly more Ghost Buster’s aesthetic about it.  The pictures are great and there’s lots of good tips along the way. We can’t wait to see what they make next year. How about a gattling version?

Model Rocket GPS And Data Logger

datalogger

Serious rocket hobbyists aren’t content with merely launching their rockets into the air. [wwgd] wants to have an on board computer to control his flights and log the data.  He doesn’t quite know how to do it all yet, so he’s starting with the basics. He has built the basic GPS data logger using an accelerometer, a GPS unit, and a BS2P microcontroller. The overall weight is 62 grams and it can record for the whole 5 minute flight. At roughly $200 though, we’d be thinking twice before launching it into the stratosphere.

STK500 As An Arduino

stkarduino

The AVR STK500 has been Atmel’s standard AVR development platform for many years. Recently though, hobbyists have embraced the Arduino. [Alessandro] has decided to bring the two together so that you can use the Arduino environment with the STK500. Unlike the Arduino, it comes with 8 LEDs, 8 switches, a variable power supply, and variable analog reference. It’s a great way to get hardware you might already have back into service.

New Battery For An HP50G

calc1

According to the author, the HP 50G is an awesome calculator. But as awesome as it is, it is powered off of not-so-awesome AAA batteries. These little batteries don’t last long under the load of the calculators awesomeness, so a mod needed to be done. The battery chosen for installation was a replacement battery for a Sony PSP. He was able to find one, including the external charge regulator board for $10.  Dropping it into the case and wiring it to charge off of the existing mini USB port looks fairly simple, very few actual modifications are necessary to the body. Unfortunately, they did end up with an LED protruding from the bottom that makes it wobble a bit, but they’re guessing that they get about 2x the battery life now.

Tethering The Kindle 2

kindle

This is not an article on how to use your Kindle’s internet connection with your computer. We’ll let [Jesse] explain why:

This is not a tutorial about how to use the Kindle 2’s Sprint connection from your computer. I don’t know that it’s possible to do so without making changes to the Linux installation on the Kindle. I do know that abusing the Kindle’s Sprint modem like that would upset Amazon a great deal.  Bear in mind also that Amazon know where you live. They know your Kindle’s serial number and thanks to the built in GPS, they know where you are right now.

What this is, however, is a nice tutorial on how to connect your Kindle to your computer so that it can use your computer’s internet connection. The instructions assume you are using a Mac, so you may have to adapt it if you aren’t. Basically you put the Kindle in Debug mode and tell it to use the USB tether for it’s network connection. This should allow not only a faster connection, but possibly a chance to see what exactly they are transferring back and forth.

Restoring Yellowed Computer Plastics

retr0brite1

Many of our cherished computers and consoles from the past have not stood up well over time. It’s not the hardware as much as the color. From Commodores, Apples, to Super Nintendos, the machines have slowly drifted towards a sickly yellow and even brown. The culprit appears to be the fire retardant chemicals used in the plastics. Amiga enthusiasts have spent the last year perfecting a technique that restores the plastic of these machines to its original splendor. Dubbed ‘Retr0brite‘ it’s a gel made from hydrogen peroxide, xanthan gum, glycerine, and ‘Oxy’ style laundry booster. The results are really impressive. If you do start restoring your own machines, caution should be used since it requires strong concentrations of hydrogen peroxide typically employed in bleaching hair.

[via Waxy]

Parts: 32KB SPI SRAM Memory (23K256)

23k256ii

Microchip’s new 23K256 is a serially interfaced 32 kilobyte SRAM memory chip, available in 8 pin DIP and 8 pin SO packages. SRAM, like EEPROM, is a data storage medium. Data stored in SRAM is lost without constant power, but it’s really fast and there’s no limits to the number of write cycles. EERPOM stores data even without power, but it’s slow and usually limited to around a million write cycles.

32K SRAM chips typically have 15 address lines and 8 data lines, like the IS61LV256AL we used on our CPLD development board.  The 23K256 requires just four signal lines, but sacrifices the speed of a parallel memory interface. It’s a great way to add extra memory to a low-pin count microcontroller without routing 23 signal traces. We’ll show you how to interface this chip below.

Continue reading “Parts: 32KB SPI SRAM Memory (23K256)”