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  1. Im pretty excited to give the ol' AT90USB162 a whirl this weekend using teensy - http://www.pjrc.com/teensy/
    3 days ago

  2. Staged coffee Robot: http://robots.net/article/2867.html BTW the ripped off audio is from "Be Human" by Yoko Kanno
    6 days ago


Comparing Old and New RC Technology

Fri, 03 Jul 2009 23:18:16 EST

An old and new rc car esc side by side
I have really put my old RC car through a lot while teaching myself electrical engineering. The servo and electronic speed control have been the most useful components I have had to experiment with. I also have used the old 7.2V Nicad battery extensively for powering breadboards and prototype projects. I realized before I left for Buffalo to finish up the Theodore Roosevelt Inaugural Site that the battery had gone bad and I also accidentally broke the old Futaba electronic speed control.

Today I drove down to Foxboro to rchover.com's storefront location and picked up a new electronic speed control and battery. RC technology has changed drastically in the last 20 years just like computer technology. In the side by side image of the two electronic speed controllers, the old Futaba is the large black box. It has forward and reverse, but requires you to turn two little adjustment knobs in order to nail the forward and reverse. Electrically speaking, you'll notice a big black heatsink on the top. Underneath that, there are nine MOSFETS setup in a H-bridge configuration in order to allow for forward and reverse control of the motor. If you look at the new speed controller I just got, a LRP AI Runner, its about a quarter of the size with many more features. The LRP requires no adjustment and is waterproof. Electrically, it only has 4 MOSFTETS too (the minimum to make a full forward reverse hbridge).

A 7.2V NiCad and NiMh battery side by side
Check out the batteries side by side. The old white NiCad battery is in an odd configuration that the guys at the rchover shop said is very uncommon these days with five cells on the bottom and one on top. The NiCad battery has half the capacity as the new NiMh battery, takes up more room, and chemically is more toxic then the NiMh counterpart.

The Real Player audio application on the Zire 71
The whole reason I got these new parts was so that I can continue progress on an in-line device for RC cars that I have been working on for a while. While reducing RC part size, I have also been thinking about how I can make this device smaller and cheaper from an electrical standpoint. After discovering the very interesting TDI Web Log some time ago while researching the AT90 series of microcontrollers, I came across teensyduino and snagged one. Teensy will allow me to prototype the in-line device much faster then making my own breakout board which in my book is a good thing. Its also going to be much less frustrating developing using this tiny guy instead of my FT232RL + Atmega 8-L setup that I have been using for quite some time.

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The True Ancestor of the Palm Pre

Thur, 04 Jun 2009 05:13:16 EST

Palm Zire 71 with blue and metalic shell
In just a few short days the Palm Pre is going to be released in the United States. Im very excited about this because I have been a major Palm fan ever since I got a Palm Zire 71 back in 2003.
Palm Zire 71 with camerea slid open
If you take a look at the design of the Pre, it pays some serious homage to its old school bretheren which is why I claim the Zire 71 to be the equivalent of its ancestor.

I purchased the device right before going to college. This has by far been the most used and valuable electronics gadget I have ever purchased in my entire life. Its alarm clock still wakes me up to this day with the options of soothing sounds including Reveille, Bumble Bee, Sonata, Wake Up, and Warbler. I use the Reveille.

The Real Player audio application on the Zire 71
I also am a fanatical podcast listener. The SD card slot of the Zire 71 allows you to carry a huge amount of podcasts or music while traveling or just walking across campus. The audio player application in the Zire 71 is actually Real Player! I think a lot of people remember that moderately functional adware loaded application from the early days of the web. The mobile version of it actually works very well. For some crazy reason the battery life of my very old Zire 71 is still phenomenal! I listen to about 6 hours of podcasts on it a week and it only needs to be charged for an hour or two. Whoever built this device really knew what they were doing.

Palm Zire 71 back side with camera slid open.  Look at that nice metal.
The old Palm OS was a great little innovative operating system as well. Im not sure if any of the readers have ever tried to use an older version of Windows Mobile, but back around 2003 when the Palm Zire 71 came out; Windows Mobile was the equivalent of a tangled mess that made no sense how to use. The Zire runs Palm OS 5.2 which is centered around the usual applications of a PDA like addresses, calendars, and taking quick notes. There was no web browser or web connectivity in this device.

Calendar application and SD Card slot on the Zire 71
While walking around with this device I have been asked a few times if its a smart phone. The metalic half shell has protected this even though I have dropped it on cement several times. If you look closely at the images you can see quite a few battle scars on the enclosure. You will also notice that I have used it so much that the surface of the writing area is wearing off.

The hidden camera while only 640 x 480 has still proven to be very cool and useful to this day. Although people expect optics to be in phones now, no one has ever suspected a standard PDA to essentially have a sleek hidden spy camera. I really hope the Pre gives all the Iphone, Gphone, and Blackberry fanboys a run for their money.

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Security Now and New Museum

Fri, 22 May 2009 22:14:56 EST

The place that TR became president
I have been a long time listener to the Security Now podcast and found particular interest when Steve was recently raising questions about why kiosks and museums run Windows on most of their machines. It was pretty cool because I wrote in giving an industry centric response in collaboration with Bruces article on the subject and they read it on Security Now Episode 196. Its around 105:00.

In other news; tomorrow will be my second day off in roughly a month. I was in Buffalo for the first half of May at the Theodore Roosevelt Inaugural site installing some pretty cool exhibits.

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