Dollar Store Digital Geiger Counter Hack

by on Dec.05, 2009, under Hardware, Tutorials

In order to take long-term readings of background radiation, you have two options:  1)  Sit quietly for hours on end, marking your notebook every time a click is heard or 2) make a machine to do it for you.  I like option #2.

Here’s how to build your very own digital Geiger counter interface for just a few dollars in parts.

1.  Head to your local Dollar Tree store and buy a digital pedometer.


2.  Pick up a 1k resistor and a 2N3904 transistor from your favorite electronics store.  Radio Shack also carries these parts.

3.  Take the pedometer apart.  Remove the mechanical lever and the thin wire which connects it to the board.


4.  Drill a hole in the back cover and insert a rubber grommet.


5.  Cut the end off an RCA audio cable (or any cable you’d like to use) and thread it through the grommet.  Make the electrical connections as follows:

  • RCA Center Conductor to 1K resistor to transistor base (center pin)
  • Transistor collector to the exposed wire on the pedometer.
  • RCA shield and transistor emitter to the spring contact.

Hint:  If you align the parts as shown in the photo (which you can click for a close-up) the flat part of the transistor goes against the back of the system board — then solder as shown.


6.  Put it all back together and connect to your geiger counter’s headphone jack.


Here’s a video of my modded Geiger counter in action, recording the counts from a nearby radium dial:

Since the pedometer is designed to take measurements at around 1Hz (the speed of a human walking), measurements taken from sources considerably higher than background will not give accurate results.

Happy Geigering!

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The Defcon 17 Badge

by on Jul.30, 2009, under Hardware

Defcon 17 Badge – demo of microphone and LED functionality from Jeremy Powlus on Vimeo.

Recorded on my BlackBerry…

This is a quick and dirty demonstration of the Defcon 17 badge. It has a microphone which has an effect on the color and brightness of the LEDs. Very cool, can’t wait to see what people do to hack them.

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Panasonic Toughbook harddrive cage is interesting

by on Jun.30, 2009, under Hardware

Ever wonder what the inside of a fully-ruggedized Panasonic Toughbook 30 looks like? What keeps the harddrive so well protected?


If you have access to one of these, you’ve probably taken a look yourself, but I figure that most of us have not. My boss has one and I replaced his HDD with an OCZ Vertex SSD today. I thought I’d take a few pics while I was at it so you could see what is going on in there.

The harddrive cage comes out of the right side of the unit, shown below:


Here is the entire cage:


A different angle:


With the top removed from the cage, showing a lot of the foam cushioning:


The HDD unit removed from the cage but still encased in plastic and foam:


A closeup of the foam blocks:


Partially unwrapped, starting to see the actual HDD beneath all the coverings:


Outer plastic case removed, just another layer of plastic and metal around the drive left:


The mess of all the parts, HDD finally liberated. Most of this stuff was attached with tape or other adhesives, so it was fun to try to keep it nice and neat:


The SSD, all wrapped back up in the (now unnecessary) padding:


At least it is now a whole lot faster than the old 5400RPM drive that it replaced. Boss = happy.

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OCZ SSD Speed Comparison on ThinkPad X60 Tablets

by on Jun.10, 2009, under Hardware, Reviews

SSD Speed Comparison on ThinkPad X60 Tablets from Jeremy Powlus on Vimeo.

My company has a bunch of Lenovo X60 and X61 TabletPCs in the hands of our salesmen. Seeking to extend the useful life of these computers, I thought I’d see how effective an SSD upgrade would be along with Windows 7 RC build 7100.
All 3 of the computers shown are X60 Tablets with L2400 processors and 2GB of RAM. The two on the left have the stock 5400RPM HDD installed, the one on the right has an OCZ Vertex 30GB SSD. The lone Windows XP machine is how the computers are currently configured. A lot of the extra time booting up is spent loading support apps, such as Lenovo’s fingerprint software, some of which is no longer necessary even in XP… MOST of which is not necessary in Win 7.
The tests I ran were standard tasks our salesmen run every day using SalesLogix which we use for CRM and invoicing. SalesLogix uses a local db via MSDE (or SQL Server Express on the Windows 7 machines).
I judge a boot process to be complete when the computer is usable… so I brought up the task manager on each machine and waited until processor usage was down below 3% for a few seconds before officially marking the machine “done booting.”
One of the greatest benefits of using an SSD in these machines cannot be quantified in this environment: the ability to safely turn off the HDD-protection software which senses physical shocks to the system and seats the HDD’s heads for a few seconds, effectively pausing anything the computer is doing until the “shocks” stop. This means that users can’t walk and launch SalesLogix at the same time or it will take a verrrry long time to open. A SSD removes this limitation and will make noticeable improvements in productivity in the field.
These 30GB SSD’s can be purchased for just over $100 right now and 60GB drives are around $210. I highly recommend them. Be certain to get the Vertex series (if you get an OCZ, that is)… avoid the Core series, they are awful.

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