Huh. I hadn't thought of that. A quick google search shows that solar cells can be used as radiation detectors, and they generally have large capture areas. I'll have to try this out.

This looks like a good background document for detecting radiation using semiconductors.

This is the type of amplifier you need as a 1st stage in your detector, should you want to build your own. (Google "Charge Amplifier" for more info.)

The radiation comes in as quick pulses (3 us or so in my circuits), so normal incident light shouldn't interfere with the detection. You could perhaps get both power and detection from the same cell.

I've been interested in detecting not only the radiation, but the direction it came from. A 3-d array of detectors with an incidence/correlation circuit can give a general idea of the direction of the source, relative to the detector. I haven't done this yet due to the complexity and expense of the detectors, but solar cells being cheap and easily available I might just try this out. Hmmm...

Thanks for the suggestion.

I've been building geiger counters as a hobby for the past couple of years. I was consulting with some people in Japan right after Fukishima helping to build reliable detectors.

Geiger Muller tubes require a specific "plateau" of voltage to get consistent results. Too low and you're not picking up much radiation, too high and you get spurious results and can burn out the tube. The correct voltage varies with individual tubes.

This isn't normally a problem, except that there's a glut of surplus Russian geiger tubes on the market right now with unknown provenance and unknown parameters. Unless you calibrate each tube to find the plateau voltage, and unless you calibrate the resulting counter with a known source, the data you get will have no predictive value.

It's straightforward for a hobbyist to put together a project using one of these tubes and get it to click in the presence of radiation, and this makes a fine project for electronics learning, but you have to take further steps to get a reliable instrument. No one ever does this. The circuits I've seen have an unregulated high-voltage proportional to the battery voltage - it gets lower over time as the battery runs down. The voltage is chosen from the tube spec sheet, instead of determining the correct voltage for the tube. Circuits have design flaws such as using zener diodes for regulation, but not allowing enough current through the diode for proper function. And so on.

I've seen lots of these hobbyist projects in the past few years, especially since Fukishima. They're fine projects and well-intentioned, but generally not of any practical use.

Virtually any semiconductor will detect radiation. What you want is a semiconductor with a large capture aperture(*), which is the area through which the radiation passes. A 2n2222 transistor will detect radiation quite well, but it's capture area is tiny and won't see much of the radiation (saw the top off of a metal-can version and use a charge amplifier).

Power transistors such as the 2n3055 have large silicon dies and therefore larger apertures - as much as a square centimeter - but this is also quite small for capture.

The modern equivalent is to use a big diode such as a PIN diode. These can be quite large, but also expensive for the hobbyist.

A GM tube has a capture area which is the cross sectional area of the tube. These can be made quite large; and as a result can be made quite sensitive to the amount of radiation flux in the area. Hobbyists can also make their own tubes with enormous capture areas - it's not very difficult.

Large diodes are available for detecting radiation, but a GM tube is simple and can be easily made with a very large capture aperture. Also, GM tube their capture efficiency (the percent of radiation that gets in which is is actually detected) can be higher than the diode solution.

(*) There's capture aperture and detection efficiency. GM tubes have an efficiency of about 10%, meaning that only 10% of the radiation that gets into the tube is detected. Diodes have similar efficiencies, depending on the photon energy and thickness of the silicon die.

Yet another reason to hate him. Fuck.

This is rather misleading. I'm very resentful (not envious, because I'm not a hypocrit) of the wealthy, though I have very little (if any) free time. There are quite a few wealthy people (who have more free time than anyone else) that aren't envious of themselves (because that wouldn't make any sense). You're attempting to draw a connection between free time and envy of the wealthy where I don't believe one exists.

Where the fuck do you live? I've had some "lean" periods in my life, where I was working 60-80 hours per week and living off one packet of ramen noodles per day. Occasionally, shit would get really bad, and I'd be living off one fucking potato per day. Thankfully enough, these periods were never long enough to kill me. Fuck you for suggesting that poor people in the US don't starve or work. Consider yourself blessed that you can afford to be so out of touch with the reality of poverty, you pompous dick.

Nope, no apologies needed. Good talk.

Although I'm still hoping that increasing levels of automation bring about a world of abundance where there is no demand for human labor and I don't have to drag my ass out of bed every morning. :)

Indeed, I'm not arguing that automation is a bad thing, nor that it necessarily decreases the demand for human labor in the long term. I agree that my statements hing on the assumption that McDonalds will show now growth of product sales as a result of their move towards automation. It's entirely possible that by McDonalds automating, former burger-flippers will be freed up to become automation engineers, increasing their income and allowing them to buy more Happy Meals, creating a virtuous feedback loop of awesomeness. The reason I'm assuming that this doesn't happen is strictly to limit the number of variables in play. Sure, automation might result in increased (or decreased) sales, or it might result in any number of unpredictable other outcomes. However, to avoid reaching a conclusion like "well, anything could happen, so who know!", I'm specifically looking at local short-term effects, ones which we can discuss with relative certainty.

I'm not arguing that increasing automation can't result in increased demand for labor. It can. Of course, the opposite is just as possible. I'm of the opinion that "it depends" is the best way we can quantify automation's effect on labor demand. I'm merely pointing out that if capital owners didn't think automation would decrease their dependence on labor (including the labor necessary to design/develop/maintain the automation itself), they wouldn't pursue it. Whether or not the laid off cashiers go on to become rocket scientists or welfare queens is immaterial to this point. In terms of short term local effects, automation (or anything that increases productive efficiency) eliminates jobs (which I believe is a good thing). In terms of long term or nonlocal effects, "it depends" is all we can say with any degree of certainty. It's possible that these former-cashiers can go and find other better things to do with their lives (like the unemployed buggy whip makers and farmers before them did), but it's also possible that the pace at which various jobs are being automated away exceeds the pace at which we can retrain workers.

I acknowledge that the economy is more complicated than I'd like it to be, and I don't pretend to know that things won't work out. I'm merely making a very small claim about a very small part of this issue: automation cannot directly create more jobs than it eliminates while still increasing productive efficiency (although in the past, the abundance of labor that resulted from increases in productive efficiency have tended to create entirely new industries and grown the size of the economy as a whole (although this is no guarantee of similar results in the future)).

The problem with critical thinking is that it makes people... critical.

It's nonsensical to do an awful lot of things that the average business will do. Critical thinking questions that. Rightly so, but that's not compatible with the way many do business.

And I dispute that you can "teach" critical thinking. You can expose students to it, and ask them to practice it, but teaching it is another matter.

I work in schools, including private schools. The difference is clear - private schools take no shit and make the kids work at learning - by rote, critical thinking, free-form learning and even attaching themselves to the IT guy outside of lessons to "help out" if they are keen geeks. They allow this, and encourage this, and aren't constrained by what's on some table of what must be learned.

They also know that they are there for the children, not solely to get "Five A-C's" so that the league tables look good to next year's parents.

The downvotes I get for quoting wikipedia, talk about crazy...

No, he's not. Reading comprehension. When I said "if you can lay off five $20k cashiers by hiring one $100k engineer to build/maintain/whatever some automation system (that does the work of those five cashiers)", I meant just that. It's my hypothetical, I can define it as I please.

What you're saying is that my hypothetical isn't accurate, and that you can replace more than five $20k cashiers by hiring one $100k engineer. Fundamentally, you're missing the point that I'm making. You focus on this "whole new industry" being created while ignoring the economics. Either automation increases productive efficiency (by definition, decreasing the amount of labor required to generate a given amount of productive output) or it doesn't. If it does, then it necessarily, by definition, decreases demand for labor. If it doesn't, then there is no economic incentive to pursue such automation. You can't have it both ways.

I think this whole discussion is little more than mental masturbation. There's no way expropriation of wealth will be legislated in this country, so talks about how well it would work have no relevance to reality. We'll see French Revolution style unrest before we see our government save us from the wealthy.

See here.

See here.

Are you saying that minimum wage is what determines the rate of inflation? Not the policies adopted by the Federal Reserve? Or will you acknowledge that it is possible to manage inflation independent of minimum wage?

In real terms, the minimum wage has fallen from $8.90 ($1.45 in 1970 dollars is $8.90 in 2014 dollars) back then. So then do wage decreases exist in a vacuum? Because the minimum wage has been decreasing (in *REAL* dollars) since then. That doesn't seem to jive with what you're saying.

There's one little piece of logic that seems to escape most people when this issue comes up.

If the number of jobs created is greater than the number of jobs reduced, then these kiosks decrease productive efficiency (by requiring more people to do the same amount of work). Since technological advances generally increase producitive efficiency, it is much more reasonable to assume that the number of jobs created is less than the number of jobs reduced.

That's why pointing to all these theoretical new jobs as though they somehow compensate for the real jobs that are eliminated is misleading at best. If you can lay off five $20k cashiers by hiring one $100k engineer to build/maintain/whatever some automation system (that does the work of those five cashiers), there is no gain in efficiency, and no financial argument for doing so. It only makes sense to automate when the costs of doing so are actually less than continuing to pay for labor, which necessarily implies that more jobs are eliminated than created (in dollar terms).

No, it doesn't. It implies that they took something. There is no value statement about whether or not they should have. And they did take something. They took a lot. That's why they became rich. People raised by wolves don't become rich.

False. Take your absurd unsubstantiated claims elsewhere.

People? A person. And I'm still laughing at him. Depardieu is a fucking tool.

It wouldn't happen here for the same reason it didn't happen in France.