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On 10/5/10 14:36 , HankG wrote:
wrote in message ... wrote: On Sep 22, 5:45 pm, Beam Me Up ScottyThen-Destroy- wrote: On 9/22/2010 8:31 PM, Sid9 wrote: "Chas. wrote in message ... Average citizens cannot be trusted with economic decisions that require balancing immediate costs and long-term benefits, according to environmentalists. [...] .CFL manufacturers claim that a 13-watt CFL emits the same amount of light as a 60-watt incandescent, but it doesn't seem to work that way in the real world. I've been in CFL-lit hotel rooms where I need a flashlight to read my dog-eared copy of The Road to Serfdom. .Warm-up time: it takes up to 5 minutes for a CFL to reach full strength, which may be related to the point above (why CFLs seem less bright). My friend has installed them in a hallway where illumination is needed only for the thirty seconds it takes to navigate the staircase. Not ideal when Grandma visits and can't see the skateboard on the stairs. I haven't tried the CFL outside but I had regular Fluorescent lighting in a barn and when below 32F they didn't work worth a damn. - I think we're are going to transition to the more - expensive LED lighting bit going from $0.30 bulbs - to $6.00 bulbs would be a hard sell so the CFL - is an intermediate to acclimate the consumers. FWIW LED Light may be coming down in Price at least for simple 3-LED Flashlights {Hand Torches} On the way back up the Hill from Stockton, CA stopped by the Dollar Tree Store in Oakdale, CA and saw a Plastic Body 3-LED Flashlight* that used 3 AAA Batteries {Not Included} for only One Buck [$1]. -hint- 'Dollar Tree' * Distributor : Greenbrier Intl.& Made-in-China Got it home and tested it with the 3 AAA Batteries installed and IT IS A BRIGHT WHITE LIGHT ! The 1"D x 3.5"L Barrel fits in the Palm of the Hand with the 1.5"D x 1.5"L Light-Head still exposed. unless you have Big Hands. The over-all shape sort of looks like this one. http://img.directindustry.com/images...ght-253681.jpg The Front Lens of the 3-LED Light-Head generally looks like this. http://www.lightjunction.com/images/...c-M3XC4-R2.jpg Just seems this year that a smaller Aluminum Body 9-LED Flashlight that used 3 AAA Batteries was selling for $5~$10 with the cheap LABs included. -but- This 3-LED Flashlight is Brighter then any of the 9-LED Flashlights -imho- HELLO Just because LEDs are so energy efficient : Please Remember Not-to-Over-Do-It ;;-}} ~ RHF http://blog.makezine.com/500-led-flashlight.jpg LEDs are "more efficient" ... but only if you narrow your definition considerably. LEDs require precision engineering to make ... and that costs money and energy and toxic crap that has to be specially disposed. WHITE LEDs suck ... they're really a BLUE LED with a pinch of white phosphor material stuck on. The problem is that the phosphor has a limited - in some cases VERY limited - lifespan. Then your LED gets dim and/or takes on weird colors. Not really an issue for flashlights ... but for home lighting that's on for hours per day every day - problem. So why not use red + green + blue LEDs to get white ? First of all, each color uses a different voltage, complicating design. The processes used also vary, so making a sheet of alternating R/G/B emitters is a super pain in the ass. Finally, next time you're out and about, look at the LED lights in the traffic signals. Oh wait, you'll probably have trouble finding GREEN ones because GREEN LEDs are unreliable for some damned reason (I recall a Scientific American article a year or so ago explaining why). So, after a year, you'll have a Red/Nothing/Blue = icky purpleish light instead of a nice white light. The hope for LEDs lies in the "organic" variety that can literally be "printed" onto a plastic sheet using tech fairly close to an injet printer. They won't be AS bright as the old kind, and they won't last AS long ... but they'll be a lot CHEAPER so you can afford to replace dimming elements. Give these about another three to five years. By then the cost/performance/efficiency should be in the acceptable range. Not meaning to hijack, but I am concerned that eventually, when I have no choice but to use CFLs, my SW radio listening will suffer. It's my understanding, that they contain a 'mini-starter' which emits RFI. I've experienced problems from flourescent fixture starters that I've replaced which will randomly blank out any AM transmissions. Flicking the light switch off, then on corrects it temporarily. Anyone comment on the CFLs? HankG CFL's and long tubes can be radically different animals. One is a linear noise source, so the attenuation with distance is proportional, whereas CFL's represent, more or less, a point source, so attenuation is proportional to the square of the distance. In other words, CFL noise falls off more quickly. CFL technology can also be quiet different than long tubes. And, with a quality bulb, inherently lower noise. Early CFL's were quite noisy. Current production CFL's tend to be much quieter, although cheaply made CFL's can still produce small amounts of noise. At a distance of a couple of meters, the noise is not an issue, but cumulatively, they can raise the overall noise floor in your location if many are used. The good news is that cheap CFL's don't last very long, and must be replaced often until they're gone. The better news is that with an external antenna of some quality, worked against a good ground, the raised noise floor can be both avoided, and/or overcome. |
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