Recent content by BenchTop

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    Doubt about laser power in laser transmitter

    If you are running a laser diode with enough current so you can see it yourself, you will should be able to detect it with almost any photodiode 100 meters away in decent conditions, easy!
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    How to let the cold work shape memory alloy to acquire shape memory properties

    I found it possible to be quite crude about it. I first wound the shape and clamped it, then ran a current through the wire until it relaxed. It did glow red.
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    Exploring the Nature of Colors: Eugene Hecht's Optics

    Painters have to consider the light they work in and the lighting for display. One wishes to have a studio with north windows for solar spectrum indirect. A painter has a closed-loop system, though- he sees what it looks like and adjusts to suit, so I'm not sure these saturation effects...
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    Polymers with piezoelectric effect

    the commercial one used is vinyl fluoride, iirc. It's 'activated' at manufacture by cooling in a high electric field. physical movement from the piezoelectric effect is extremely tiny. you wouldn't be able to feel the expansion but you could feel vibration if you applied modulated power...
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    How Can I Ensure Each IR LED Activates Only Its Corresponding Phototransistor?

    If the question is how to get the motors on separate channels - and if you intend to use an ordinary IR remote controller, like for TV's and such- the way those work is that each button causes a serial code to be sent (in the ones I've used) on a 32KHz 'tone' (the IR LEDs are modulated at...
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    Monitoring a Live, 80W, 12VDC Load

    Lol. Good thing there are no psychologists replying - you'd hear about how to regress your amperage through hypnosis or something. Why not... wrap one of the power leads around a toilet paper derder? Then, turn on the power, set a cake pan under the derder and dump a handfull of paperclips...
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    How can I create a accurately-measured conductive strip for electronic projects?

    http://www.tedpella.com/SEMmisc_html/SEMadhes.htm#anchor1148917"
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    Can a Master's Project in RFID Still Offer Unique and Valuable Contributions?

    An ingestible thermometer would be really useful for a project I'd like to do.
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    Build Your Own Homemade Dyno for Small Engines

    It means don't use any controls in the circuit, just the nichrome resistance filament - the stove element is acting like a 1000W light bulb. A regular commercial element used below its rated capacity needs no cooling - in fact, you may wish to characterise its resistance at a stable working...
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    Crazy water pressure formula implication?

    I just stuck a piston in the column and I had most of a hydraulic jack. That cleared it up for me.
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    Help Design a Human-Powered Helicopter

    Do the rules prohibit offsetting the load with, say, lighter than air wings?
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    Build a Robotic Lawn Mower: Is It Worth Pursuing?

    Quite right. The typical set of variables, as in milling, is feed, speed, materials and number of teeth. In point of fact, however, the blades do virtually all their cutting on the outermost edge and the rest of the blade mostly provides unneccesary friction and a little shaft to wind crap up...
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    Build a Robotic Lawn Mower: Is It Worth Pursuing?

    Yes. DC motors can be speed controlled by pulse width modulation or by voltage, with feedback or without. You'll need to know more about the motors ratings to proceed with design. Higher voltages means more expensive.
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    Crazy water pressure formula implication?

    I think I get it now. It really does take that kind of pressure to lift that column. Thanks.
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    Crazy water pressure formula implication?

    I did the area and volume and 1 g/cc. You can't get PSI without putting Ps on top of SIs. When you add a tiny amount of mass, the sealed, enclosed horizontal surface where the little column empties represents the SI you added the minuscule fraction of a P to. At that level, every SI of the...
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