The Digg.com headlines for today include research about bacterium that produces electricity by consuming sugar. The Escherichia coli bacteria actually excrete hydrogen after consuming sugar. An electric fuel cell is then powered by the hydrogen.
The team fed Escherichia coli bacteria diluted caramel and nougat waste. The bacteria consumed the sugar and produced hydrogen, which they make with the enzyme hydrogenase, and organic acids. The researchers then used this hydrogen to power a fuel cell, which generated enough electricity to drive a small fan.
They are also using the bacteria to recover palladium metal from the spent catalytic converters of older vehicles.
If you know me on a more personal basis, then you know that I have been experiencing some issues with several projects/articles in the works for this site. Up until now, I did not have my own oscilloscope. Usually I am able to make due, but recently it has been making things harder than it is worth.
After some research I happened to find a deal on a new Instek GDS-820C DSO. The offer was impossible to refuse and cheaper than the GDS-805C. Besides the obvious increase in sample rate, the GDS-820C comes standard with USB and parallel ports along with the RS-232 port, but GBIP is still only an option. These digital storage options will allow me to post pretty pictures on the blog!
This oscilloscope samples at 100MSamp/sec and is capable of 150mHz operation. They claim an ‘effective’ sampling rate of 25GSamp/sec when viewing repetitive signals. In comparison, Tektronix base model samples at rates up to 1GSamp/sec.
At 150mHz it will be hard to see much if the signals are not repetitive! If you know anything about Shannon’s Sampling Theorem, the effective sampling rate makes 150mHz operation seem… possible. Without this hack, the scope would be limited to half the sampling frequency or 50mHz. I could have paid more for a Tektronix scope, but the hardware would have been limited to 40mHz, mono anyway. This will suit my needs.
Update: If you view a signal sampled at over 100MSamp/sec, then you can tell it is making due with the effective sampling rate. I am not sure if this really matters because I do not have access to signal over a MHz at the moment.
Recently, RFID was in the headlines for being crackable by cellphone. At first glance, this article does not seem very extrodinary. SHA-1 encryption is weak and any engineer knows a cellphone is just a tiny computer with an antennae. However, the headlines fail to tell the entire story.
If you didn’t know, RFID tags do not contain batteries. Instead, they draw power electromagnetically from the reader. Shamir uses a directional antennae to monitor the power consumed by the RFID tag.
“The reflected signals contain a lot of information,” Shamir said. “We can see the point where the chip is unhappy if a wrong bit is sent and consumes more power from the environment…to write a note to RAM that it has received a bad bit and to ignore the rest of the string,” he added.
By monitoring power consumption, they are able to tell exactly which bit in the pass-phrase incorrect. Considering that half the bits could be guessed correctly as zero or one, it would only take 128 tries to crack a 256 bit pass-phrase. On the bright side, it ignores the proceeding bits instead of giving them away as well.
If you were wondering, a cell phone has all the hardware necessary to replicate this attack. Hopefully, 3rd party software is restricted from processing incoming RF signals directly.
Spark Fun Electronics has come through once again and is offering a color LCD 128×128 Nokia knock-off. If you ever wanted to do a project with a color LCD, it just got cheaper! Just remember that it’s a small mobile phone LCD and reliable at about arm’s length.
We’ve got the LCD and example C code for $20. You really can’t say no! We even sell the loose connector for $1 in case you are worried about soldering the tight 0.5mm pitch.
In the increasingly popular world of light-emitting diodes (LEDs), an emitter’s light output per given input (efficiency), heat management, and small footprint are critical. So if you can make dramatic advancements in just one of these three areas, you’ve done a lot.
LED performance is quantified by the input power (Watts) required and the output intensity (lumen). A lumen measures the luminous flux (light energy passing) through a particular surface. It accounts for light emitted in all directions. The new Luxeon K2 LED breaks all these barriers.
A white light output at a color temperature of 6500 K with 1500 mA of drive current and a forward voltage of 3.85 V produces 140 lm.
This corresponds to 4 W of input power and 35 lumen per Watt. Comparatively, a standard incandescent bulb emits around 855 lumen at 60 Watts or 14 lumen per Watt. Current LEDs perform at about 20 lumen per Watt. Most professionals don’t expect LEDs to be used for mainstream lighting until they reach about 100 lumen per Watt.
Scientists at Japan’s NTT Corp. have designed and fabricated silicon transistors that are controlled by the flow of individual electrons.
The amount of energy required to move a single electron increases significantly. That, scientists said, makes it possible to control individual electron motion and current flow…
Low power transistor logic my be ready for an update. Want to see exactly what’s going on? Check out this close up!
This colorized micrograph shows three tunable gates across an electrical channel in a single electron tunneling (SET) transistor.
The Motley Fool has an interesting interview with long-term forecaster Paul Saffo of the Institute of the Future entitled, New Year’s 2016: I, Robot Investor. About half way through, the following text finally becomes of interest:
To me, it is pretty clear what the next big, out-of-the-blue industry will be. And it will continue the pattern of a new industry emerging every decade or so. In the ’80s, it was the personal computer… Now we are teetering right on the edge of a revolution in the robotics industry – consumer robotics in particular.
His job is to watch for the type of disruption recently caused by iRobot and Intuitive Surgical. “60% of Roomba owners had given their Roombas names.” He also mentions iRobot is delivering an ‘advanced’ product at a reasonable price, a sign robots are becoming practical.
In my opinion, this is not extremely out of the ordinary. What percentage of Roomba owning geeks has a name for their car or computer? I am sure it is very far above the national average. From an engineering standpoint, the price of the Roomba is a function of its simplicity, not price drops at a warehouse or research and development.
Although I am skeptical, I do believe that robotics is where the mp3 player was 6 years ago. The field is just waiting for something the general public will go googly eyed over.
