μblog: engineering from the trenches

1.) Install the GNU Privacy Guard for your system

2.) Download and install Enigmail (Thunderbird extension)

3.) Restart Thunderbird

4.) Click on the Encryption icon and fill in the information (generates keys, starts keychain, etc)

5.) Enjoy a bit more privacy!

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Today, I found the Faraday, Helmholtz, Kelvin and Newcomb lectures from the Harvard Classics, 1910 edition. I was reading the William Thomson, Baron Kelvin of Largs, lecture on the wave theory of light, and came across this passage:

“The school system seems to be very admirable, and I hope the teaching of the metrical system will not be let slip in the American schools any more then the use of globes. I say this seriously: I do not think any one knows how serious I speak of it. I look upon our English system as a wickedly brain-destroying piece of bondage under which we suffer.”

The lecture was delivered on 29^th September, 1894, at the Academy of Music in Philadelphia.

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I found this German site today that aimed to test what the minimum hardware requirements for running Windows XP really were. They got it down to 7Mhz with an 18MB of ram (system info lies a little bit.) Important to note that XP did not install on a 486, probably due to difference in memory controllers, but 8MHz Pentium is not too much of a step up.

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Sometimes it is necessary to probe two sides of a single PCB with multiple probes while keeping your hands free to turn some knobs. This can be accomplished by using expensive PCB vices with specialized probes, or you can make your own using some optical breadboard equipment and old micromanipulators. I put this one together by using some spare Thorlabs parts that were lying around the lab and some electrode micromanipulators from the early 80s. (more…)

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Over the past week, I have been pretty busy with data analysis and designing a field controller for a colleague. The field controller is a device which accepts a program voltage and sets up an electric field in a recording chamber which is proportional to the program voltage regardless of the chamber conditions (meaning solution conductivity changes.) The field controller also maintains optical isolation where the output stage runs off batteries. Most of the field controller electronics are voltage-feedback op-amps with multiple feedback paths to give it the function, with an LOC110 optocoupler from Clare to give the isolation. This is a pretty nifty IC with two matched photodiodes to give a feedback control and a large bandwidth (>200KHz) so it has plenty of useful applications. Below is the datasheet and an app note dealing with isolated amplifier design.

( LOC110.pdf ) ( AN-107.pdf )

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For some time now, I have been looking at the RFID offerings from TI due to their simplicity and high levels of integration. Sure, the inductive coil is not on the die, but that’s not such a huge problem. I have a design idea where I can simply connect the RI-TMS3705ADR to an Atmel 8051 and connect that to PC via RS-232 to form a simple interface. Because this is a low frequency device (~130Khz) the antenna can be a simple set of wire loops. For now, I must wait for the universal programmer to return to program the 8051 and some free time to come up to put this thing together. Below is a datasheet, application note and training presentation fro TI.

( RI-TMS3705_ds.pdf ) ( lf_reader_intro.pdf ) ( LF_20TMS3705A_20ASIC.pdf )

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After talking to the manufacturers of the eeprom programmer, we both decided that I should send it back to have it checked/replaced, so no rewritable roms for a week or two. In the mean time, I found a copy of Super Mario Brothers 3 at a local shop. I also decided to open the NES and follow the connector re-conditioning directions for the best experience. Now it’s time to get the power up and win the game.

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A long time ago I found a small script somewhere that fetches http://www.livejournal.com/stats/latest-img.bml (dynamic file containing recently added pictures on livejournal) and parses it so that you get to see the picture and the post it was placed in. For a long time, this was on my work server, but I decided to move it here, since I now have legitimate hosting! Anyhow, it has become the most accessed page on microblog.routed.net (due to a redirect from the previous url) so I figured that the rest of you wanted to see too: latest images from livejournal (image list is computer generated, some images may not be in good taste and may not be work-safe.)

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I got my Neuroscience 2006 abstract in at the last minute after many revisions. It seemed that the rest of the people who are applying to present at the conference also tried to submit their abstracts during the last afternoon, and as a consequence, it was one huge denial of service attack with connections timing out. The bigger issue is that I now have to process data and generate support for the statements I so easily submitted. The good part is because of the move, we won’t be able to do experiments over the summer, so it is all about data analysis. As a refresher for myself, I will try to write up a few basic documents that will cover time series analysis, both in frequency and time domain, and hopefully they will be interesting to read.

( nchernyy-sfn2006.pdf )

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Some people say that instant noodles are the ultimate lazy person’s food, which may have indeed been the case until the invention of the rice-maker. To prepare for moving, I bought a rice cooker today so that I could try it out while I was in the DC area and could exchange it if it did not work too well. I settled on this “MICOM-FUZZY” from Zojirushi. The features are fast cook time (20 minutes) and extended “keep-warm” time which should be in the neighborhood of one day. The capacity for this unit is 5.5 “cups” (where one cup is 0.18L and a US cup is ~0.25L) which roughly translates to 2600 kcal of energy assuming standard, long grain, white rice. Given that washing the rice can be considered optional (assuming you are super lazy) so all you need to do is to put in the rice, add some water, push a button, and wait a little bit and voila, you have enough food (which lacks most nutrients other than energy) for one day. Sounds a bit quicker than having to cook noodles for breakfast, lunch and dinner!

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