About Me

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I previously worked on Virtual Reality and other hardware at Valve.  I currently work at Google[x].

Prior to starting at Valve, I built computer peripherals such as keyboards, mice, and joysticks that were designed to be used inside MRI machines.  My company, Mag Design and Engineering, sold these devices directly to researchers at academic institutions who used them to publish scientific papers in peer-reviewed journals.

After work, I spend time on many different types of projects that usually involve circuit design, machining, material selection, and general fabrication/hacking.  My favorite place to be is my home workshop.

ben dot krasnow at gmail




Monday, July 16, 2012

Molecular gastronomy (playing with food): "reverse" spherification maraschino cherries

I made a puree of maraschino cherries and added 2.5g of calcium lactate gluconate. I then dripped this mixture into a solution of 2.5g of sodium alginate in 500g of water. A gelatinous skin is formed at the interface between the two liquids, forming spheres of cherry puree. This process is known as reverse spherification. I bought the chemicals here: http://www.amazon.com/Experimental-Kit-Artistre-600-grams/dp/B0045KOOXU

Monday, July 9, 2012

Follow-up: Attempting to make X-rays by unrolling Scotch tape -- Success?

In this follow-up video, I show that I was able to get a P47 phosphor disc to illuminate when unrolling tape in the vacuum chamber. The blue x-ray intensifier screen did not illuminate although it was also in the chamber. Also, it seems the P47 was illuminated through a thin copper foil, though I will have to do some more tests to believe this.

Attempting to make X-rays by unrolling Scotch tape (negative result)

A few years ago, a research group posted a video showing that X-rays could be created by unrolling scotch tape in a vacuum. The idea is that the static charge generated by the mechanical unrolling process would cause electrons to accelerate to 50KV (or so), and then produce x-rays when they slam into something. I tried to recreate this experiment, but I had pretty weak results. I may need a much larger vacuum pump to keep the pressure in the chamber very low while unrolling.

Sunday, July 8, 2012

Creating X-rays with a standard vacuum tube

I forced an RCA 811A tube to produce some X-rays by operating the tube in cold-cathode mode at about 20KV and 150uA.  The glass fluoresces nicely, but I didn't get any light from my X-ray intensifier cassette.

MightyOhm's geiger counter kit: http://mightyohm.com/blog/products/geiger-counter/