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  1. P

    Decent Table Saw Recommendations

    Consumer use or commercial use? Although one guy I knew (now deceased) bought cheap stuff multiple times and it was still cheaper than buying commercial use stuff once.
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    Custom led advice?!

    Verily, Sires & Miladies, this is the thread that will not die! :(
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    Toroidal transformer for 12V track lighting?

    It's much worse than that. I think you can connect dissimilar transformers in series or parallel for current sharing or voltage increasing with some cases requiring resistors to alter the current sharing. The two cases to be checked are full load and no load (if the application ever has the...
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    Auf wiedersehen

    It'll cost ya'! :D
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    Custom led advice?!

    IIRC, red, green, and blue LEDs all have different design center voltage values. It used to be for a red indicating LED at 20 mA and a 5v supply you assumed a Vf of 2v and so it was a 150 ohm resistor and you lived with the brightness you got. By mistake I drove an LED with a TTL output...
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    Problem with neighbour

    If I could improve on this, I would. I can't.
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    Custom led advice?!

    Vs R LED v I 6 125 2.5 0.028 6 125 3.5 0.02 6 125 3.5 0.02 6 125 4 0.016 12 425 2.5 0.022 12 425 3.5 0.020 12 425 3.5 0.020 12 425 4 0.019 Assuming the only variable is LED voltage, if 16 to 28 mA gives an unacceptable variation in LED brightness, you could go to 12v if you have...
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    Orange Antifreeze

    Wikipedia has a good article on antifreeze. Apparently even the car makers are not sure in some cases what not to use for long, trouble-free operation. The dye coloring is another issue.
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    Joist span

    [/url] Yes, the span tables incorporate deflection and strength of material for the joist and the joist strength depends on the material and shape. If you pick a table entry I guess some of us can say whether that choice will work, and why or why not.
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    Toroidal transformer for 12V track lighting?

    I believe I've thought of that. If V1, Z1 and V2, Z2 are the voltages and winding impedances then paralleling them with no load would give an I of (V1-V2)/(Z1+Z2). If this I is less the winding current rating I'd say it's OK for one winding to sink or source this much current. And with a...
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    Auf wiedersehen

    Formatting is bad, but, thanked percentages posts\/ thanked \/ percent 770 0 0.00 999 3 0.30 so out 999 posts there were 3 thanks for a percent of 0.3 264 4 1.52 26245 789 3.01 2463 339 13.76 623 19 3.05 2940 7 0.24 41416 1340 3.24 46241 2545 5.50 1836 237 12.91 708 5 0.71...
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    Custom led advice?!

    I'll post some examples.
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    Custom led advice?!

    The hour is late, but having fortified myself with milk, sugar and bread I now realize that your use of qualifiers is beginning to sound like this http://en.wikipedia.org/wiki/No_true_Scotsman fallacy. :D
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    repair not replace

    This 150/92 ratio represents what more than half of their customers will go for, but your decision seems easy if you can find a drop-in replacement. Yeah, a growler. You might be able to sand down the commutator yourself and, depending on how many commutator strips there are, take many ohm...
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    Custom led advice?!

    Try it. Assume the LED voltages at 20 mA are approximated by 3.5, 3.5, 4 and 2.5v (the unspecified low end of LED voltages). With three LEDs this is 4x3 values. Then add voltage distribution, assume 12.8, 13.5, 14.4, 14.4, 15. Then add resistor tolerance, assume a normal distribution with...
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    Custom led advice?!

    Not to add fuel to this fire, but if you made 10 or 100 of these circuits and you knew the distribution of LED voltages at some current beforehand, you could predict how many circuits would have some or all LEDs lit and how many would have no LEDs lit and how many would have LEDs lit...
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    Auf wiedersehen

    3 percent of posts thanked is in the lowest 1/4 th 13 percent is in the top 1/4 th 7.2 percent of posts = average
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    Orange Antifreeze

    AFAIK, which is not far, you shouldn't mix different antifreezes and the antifreeze has to be compatible with the engine cooling passages insides. If you ignore these warnings, I guess you'll have reduced performance or have to replace your coolant more often. After hours of Web research you...
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    Toroidal transformer for 12V track lighting?

    Will an electrical engineer do? I'd put the windings, properly phased, in parallel for better voltage regulation. Signed Physically Repulsive Engineer
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    Custom led advice?!

    The voltage applied to this string may vary from below 12.8 vdc to 15.5 vdc. You need to convert this voltage source into somewhat like a current source but for statistical reasons it's less important if you have 10 or 100 LEDs in series.
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