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    Lenses and reflectors

    Brilliant lightfooted, found the side emmitter in 2 minutes, !:) Now i need reflective stuffs, preferebly both preshaped and also paint that i can use, im thinking of the high chrome stuff you see, or if any other ideas please ,
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    Lenses and reflectors

    Ive not posted in a while. I am looking to make my own led lights for a bike.unhappy that leds on cars and bikes are dazzling i wish to create a led lens or/and reflector. Learning that fillament light bulb car lights where blocked from front facing beam, ie they had to shine forward from a...
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    Scientific information requested

    I am after some scientific information regarding laser beam strength degredation in air. I do not know whether anyone has any good information they could share please. Information on Atomic saturation of the air Electron scattering of the beam General loss through the air Plasma heating of air
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    Drivers/ regulator input voltage current effects on output quantity

    It was my belief that the driver characteristics made the output current constant(within reason) no matter what the input current/voltage was. Recently having bought a driver that was rated at 5 to 35 volts and having tried it the output was Far beneath what was expected, this was sort of...
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    So we dont get true ions !

    I see Mario. Liion are a good battery for discharge rate, charge holding, memory effect etc, i dont really see much more of a drain problem as compared to NIMH as drain between 3 aaa nimh is acceptable for most applications, I know there are higher drain occurences but for most applications they...
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    So we dont get true ions !

    Well thanks for all the input. I didnt really think the discharge rate of the lithium thionylchloride was so low. But from a safety point Of view is cobalt any less dangerous or toxic than lithium ? A d cell nimh is 170g and has 11wh, a lion battery is roughly half the weight and has 7.5 wh...
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    So we dont get true ions !

    Found this on battery university, 500w/kg .Are we better of with NiMh as they have a similar capacity to lower lithim capacitys ?
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    Help regarding driver efficiency calculations

    I put a thread asking for driver reccomendations a while ago to no sucess. What do you think to these ? http://m.ebay.com/itm/3w-Constant-Current-Power-LED-driver-Input-3-6v-Output-700mA-with-2pcs-7135-IC-/111855113500?nav=SEARCH These look like you select your resistors yourself And...
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    Help regarding driver efficiency calculations

    Yep its got the coil, (-nduction coil)which i thought was needed to convert using the switching methOd. Its got the chip on it for the switching too. It is a buck by name. I did wonder whether the metre was reading peak current and voltage on the way in ? Rather than the average. Yep the sums...
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    Help regarding driver efficiency calculations

    Could some one check these calculations, as Ive bought yet another driver, and apparently its doing a resistor job and dissipating the surplus current. Pre driver - 3.69v and 150ma giving 55.4 watts Led side - 2.77v and 143ma giving 39.6 watts Efficiency of 71 percent, which is basically...
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    Uk shipping small quantity easy cree xpg2 ebay or similar with R4 binning or above?

    Do you have any easy ebay or similar shop links to somewhere that sells to the uk in small quantities. Importantly it should have binning info on it. Dont know whats happened, all the ones i purchaced from before have disapeared and i can only confirm some are Q5 rated. Help would be apreciated‎
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    Quality 18650 External Battery Bank ?

    well this tomo one needs initialising from a wall charger if all the batteries are taken/fall out. ive not tried this one http://www.amazon.com/dp/B00IM3NZ86/?tag=cpf0b6-20 this one you can short badly, red and melted terminals, again not tried but its on the reviews ive read. it looked the...
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    Quality 18650 External Battery Bank ?

    I have seen the little charger boards, but as for the moulding for the case, wiring sockets and 2 diodes a battery it would be quite amaturish. I suppose i could canibalise and modify one i buy, but i was hopeing to just get one ready made. I am quite suprised i cant find one by nitecore actually
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    Quality 18650 External Battery Bank ?

    oDonees anyone know of an 18650 external battery bank/charger that's well built and comes with reverse polarity/low high volt protection etc. I cannot find one, all i can find is these on amazon. http://www.amazon.com/gp/aw/s/ref=is_s?k=18650+battery+bank Theyre either fragile or not...
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    Underpowering COB leds by a significant ammount ?

    Can I under power LEDs of the cob variety by 90% or thereabouts so i can produce a diffused light, will it actually drive or remain non luminous. I realise that this isnt a cheap way of doing things.
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    pleas reccomend an efficient voltage regulator/driver with user definable output

    Im looking for a 5v 2A driver or self build circuit with current regulator with; Constant linear current, no pwm High efficiency, i can get 70% from a 10w resistor User defined levels, so no cycling through strobe etc, preferably with resistor switching Weight or size is not really a...
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    what IS a 1-watt LED emitter ?

    In efficiency terms 1w seems to be the most standard emmitter power value, after that the efficiency drops considerably, I cant vouch for cob leds as it gets a little complicated. I suppose 1w is still considered as low as you can go with reasonable output, whilst still having an efficiency...
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    Review: Mpowerd Luci Light ( Luci is different! )

    I don't mean to be a bother but are the bathroom photos with a camera flash, as it certainly looks like that in the photos that the bright light from behind the door is a source of illumination.
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    I need help converting 3xAA Headlamp too 1x18650

    Will the lamp take an 18650 by just switching the battery box? As the 18650s have a lot more power a lot faster( higher draw) some drivers I have seen listed are not suited to simple battery change. The headlamp listed looks to have a very small lamp at the front considering its adjustable, so...
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