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adoyle

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The text says “a current with a potential of up to 1 volt.” The key word is potential, i.e. electrical potential whose SI unit is the volt. That must be the amount of potential that this particular chemical reaction can create. Since the current probably depends on the amounts of the chemicals involved, the article doesn’t state that.

March 20, 1996. Before that I worked on so many different computers that I didn't manage to keep a continuous archive. Early on, my files would have been on punched cards, then 9-track tape, then 8" floppies, etc. I do have some usenet postings from 1981 that are still viewable. The oldest is here: https://groups.google.com/g/fa.unix-wizards/c/o2fAr_mGPa8/m/... At least I no longer feel I'm "naive in terms of UNIX" as I stated in my posting :)

Sketch 3 released 12 years ago

I found v3 on the App Store by going to the Sketch 2 page and noticed "More by Bohemian Coding" on the right side had a link to the Sketch 3 app store page.

NASDAQ:FB 14 years ago

I just got this on Fidelity:

Attention: FB order execution slowness Certain marketplaces are experiencing slowness resulting in delays in execution for Facebook orders. Industry technology teams outside of Fidelity are working to correct the problem. This slowness is being experienced by other online brokers as well, not just Fidelity. This has been reported as a market-wide issue. We do not yet know when the problem will be resolved. We appreciate your patience.

The fine for jaywalking in Massachusetts is one dollar. It's unheard of here to be stopped for crossing the street anywhere. When I first arrived in Boston, years ago, I was waiting for the light with a bunch of other pedestrians when a cop came along and said, "what are you waiting for? this is Boston" and crossed the street with the rest of us behind him.

My math teacher in the 8th grade in 1971 made up a virtual machine with an assembly-like instruction set. He had us write programs and then 'execute' them by thinking about them as though we were the VM. Once we got the hang of that, we learned Fortran and got to send punched card jobs to a computer on the other side of town. Turnaround time was measured in days. It's been a wild ride since then.

In the US, these discussions are pretty much always about gross pay. People also don't include the value of benefits other than bonuses, and as you see, bonuses are explicitly stated. I gather that in other countries it makes more sense to talk about net.

I often go to the comments page for a submission first, then click the article link. Particularly if it looks like it's going to be one that drifts off. That way the back button puts me in the right place, even if I come back to it hours later.

You definitely can hit different sweet spots with plugs vs Minis. That's one reason I was playing with the Eee Box. They cost just under $300 with a decent amount of RAM and disk, plus HD DVI out. If you don't need a display then even that's overkill.

Reliability is a key factor for me with low-power being important, too. I've been running Mac Minis as servers since they first came out. Right now I have ~25 of them running at the MIT Museum, about half of those run exhibits and shut themselves off from 11PM to 8AM, a couple are used for desktops, the rest are running 24x7, some as servers, some as development machines. I've never had a Mac mini die. I'm in the process of moving our internal file server from a PowerMac G5 to a Mini.

We just got our first new, low-profile Mini and it's great. Not having to deal with the power brick is a huge win, and the power cord seats much more firmly than the old cords do.

I'm also experimenting with two Eee Box B202's running Ubuntu. One has been running 24x7 for the last 6 months without any problems.

Plug computers are interesting and for a while I thought they could make good controllers for touch-screen kiosks. But the iPad pretty much blows away anything we could put together with a plug, a USB display driver and a monitor (except in screen size).

If money is not a problem, then I think you should not try to hit the perfect solution the first time. Trying to do that will make it harder to get started. I had to build a linear motion platform last spring. Since I had never done anything like that before I decided to just start buying stuff and testing it. I started with some small servos and brackets from Trossen Robotics - http://www.trossenrobotics.com/c/hobby-servos-for-robotics.a... and some Phidgets USB controllers from http://www.phidgets.com/

I started with the servos because it seemed cheaper and I could start without having to build a lot of stuff.

Then once I was happy with being able to control a two-axis setup with a little webcam on it using Python on a Linux box, I moved up to some 185oz-in steppers from Keling and some more Phidget stepper controllers. One of the big motors with a toothed belt can lift a full can of paint and hold it indefinitely.

I chose the Phidgets over Arduino because I didn't want to have to simultaneously learn a new toolchain while I was concentrating on the mechanical stuff. I figure I can always go to an Arduino or other controller if I need to shrink things down.

Having now worked with the steppers, I would second the idea of using DC motors with some kind of external feedback, maybe optical shaft encoders or something. Even with steppers, where you can count the number of steps and know where you are, you still really need to be able to run it into a limit switch in order to find some kind of a zero point.