posted December 08, 1999 07:55 PM ------------------------------------------------------------------------ No additional work, energy, charging, or expense. ( but only if you just use it 12 hours a day )

I have made for myself white LED flashlight bulb replacements. The single LED lights are dimmer than regular bulbs (duh), but they have some very important redeeming properties:

The LED is rated at about 11 years continuous when properly powered, while regular flashlight bulbs last only 10 to 50 hours before they burn out. (LED outlasts 1700 to 9,000 flashlight bulbs. At .75 per bulb thats $1000 in savings on bulbs alone, not to mention the batteries.)

The LED will not destroy your night vision. (unless you look right into it) This is as important in the house that is dark just as much as in the bush trying not to get whacked.

Can be used with either 3 alkaline (or 4 nicad) cells for "full power" or with 2 alkaline (or 3 nicad) cells for "forever mode." (4 days on 3 AA versus 4 weeks on 2 AA, 30 days on 3 D versus 6 months on 2 D alkaline cells.) (incandescent buls work in narrow voltage range, either burning out or being too cool/dim/red)

LEDs run cool. No burning/melting and hard to detect unless you actually see them.

I am a light adict. The thought of losing the ability to turn on the lights and SEE whenever I decide I need to is somewhat frightening. Many people are trying very hard to preserve all of the conveniences and real blessings we enjoy now as part of a very complex economic and technological system, no matter how much of the infrastructure gets damaged. If the goal is to simply be able to not trip over things, find your loved ones safe in their beds or see if the lid is up or down on whatever you are using for the purpose, you can get away with very little light, and very little money. (Maybe 12 to 30 dollars more if you purchase pre-made bulbs.)

For example, the white 2 D cell closet light that Walmart sells (about $3) will run a white LED ($3 to $6) for about 6 months on 2 new alkaline D cells (about $1 each) of almost any odd brand. ($11 total for 6 months continuous on time.) I have one in my own bathroom right now, and expect it to be able to light until next June at least. Is this a lot of light? NO!!! It does give more than enough light to see the fixtures and show where the big battery lantern is if needed. This is much safer than candles any day!!

The numbers work out about the same for any 2 or 3 cell flashlight that takes a "regular" flashlight bulb, and I have given LED flashlights to just about everyone in my family, and will give more for Christmas. The red and yellow LED bulbs are pretty popular with the kids too.

LEDs can also be used in 12 volt systems easily.

Sources of white LEDs:

White LEDs are available many places including Holly Solar at www.hollysolar.com, Jade Mountain at www.jademountain.com, Hosfelt Electronics at http://www.hosfelt.com/ (I really like the 7 candle power ones I got from Hosfelt, but they are $6 each).

how-to guide and construction instructions: http://www.geocities.com/SiliconValley/Bay/4397/ look in the left column for pictorial directions

-or- http://people.aero.und.edu/~nordlie/astronomy/redlight.html shows more of a clear line drawing with text description. http://www.kiyoinc.com/WRP130.HTM has lots of different views and experiences in LEDs. And other useful information.

Holly Solar at www.hollysolar.com has ready-made 3 LED bulbs for 3 cell flashlights (like big maglite) for under $20. Good brightness. About a week run time on 3 fresh D alkalines. Maybe two months on 2 D cells, again, rather dim. Other sources are Real Goods, Jade Mountain, C Crane, etc. The bulb will save more in batteries than it will cost you. The 3 LED bulb above will last about 1/3 or 1/4 the time of a single LED bulb.

(WARNING: I have not proven that the 3 LED bulb will work on 2 alkaline cells or not. This is my guess based on every other white LED I have encountered. Unfortunately someone will have to make this experiment for themselves.)

On the average in the numbers I have seen, a child dies for about every 100 house fires of any size. (and this is when the fire departments exist) Please do not leave any temporary flame unattended. I would rather see LED lights all over the place than to make a bit of a living or killing off of these. And besides, I am a terrible marketer. Buy one somewhere, make one for yourself, make a bunch for the neighorhood. The home you save may be your own.

-- Ed (ed@lizzardranch.com), December 11, 1999

Answers

Just purchased an LED 3-head light bulb to go in one of the mag-lite flashlights. Works great! Just hafta get used to the white colored light.

What/how well does the red one do for night vision? Any experience?

Diane

Bought the bulb from Real Goods, at one of their new retail stores...

http://www.realgoods.com/

Replace Standard Flashlight Bulbs With Battery-Saving LED
Dramatically Prolong Battery Life of Most Flashlights

http://www.realgoods.com/cgi-bin/ reframe.pl?search=/products/lighting/37-362.htm

Happy with your existing flashlight? No problem. Replacement leds use 80% less battery-power than incandescent flashlight bulbs. The diodes have no fragile filaments, are virtually impervious to on-the-job shock and vibration damage, and they test out at 11 years of continuous use! Three-diode led clusters (in a standard 9mm flashlight base) fit any flashlight with battery configuration from 2 AA to 3 D cells (alkaline or nicad). Any 3 battery configuration gives the brightest illumination; light produced is a vision-saving moonlight white or night-vision red, ideal for close tasks in the dark. We also offer the 3 D-cell, 12 aluminum Mag Lite. shown. USA.

37-362 LED Replacement White Flange $29.95

-- Diane J. Squire (sacredspaces@yahoo.com), December 11, 1999.

I kept one of my white-LED lighting systems, consisting of a super- efficient pulse-width-modulation driver and voltage regulator (which provides more efficient use of power, permits brightness control, and protects the LEDs against excess voltage) and a 36-LED array of Nichia's brightest white LEDs, all mounted into a lantern-style flashlight. Power supply is eight 'AA' batteries of alkaline, NiCd, or NiMH flavor.

Alkalines need to be replaced every six months (!) and NiCds and NiMH do well with a full charge every four months.

White-LED lighting systems are worth the $ for emergency or off-grid use, without any doubt. They have their disadvantages, with cost bein the most notable one, but still, is a little more expense worth not having a fire risk?

O d d O n e, who would love to do another LED bulk-buy if the world remains functional enough...

-- OddOne (mocklamer_1999@yahoo.com), December 11, 1999.

Ok ED...pretend you're trying to explain this to a 5 year old...well it's not quite that bad but close...grin. I had purchased those closet lights from WalMart in the past and in testing to see how long the batteries would last..well...let's just say I took them both back. If they would indeed last as long as 6 mos. which led bulb should I get. I went to the Hardware website and wasn't sure which one to get.

I also purchased a couple itty-bitty-booklites at a yardsale a couple weeks ago. If I got an led bulb for those would it fit? and would you be able to read without eyestrain?

Last question I promise. Do you just unscrew the bulbs in these lights as you do in a regular lamp and then screw the leds in? I've personally never messed with a flashlight bulb. The flashlights were usually so cheap I'd just toss them and buy new ones.

beej

-- beej (beej@ppbbs.com), December 11, 1999.

Love them LEDs, the Nichias are the kind...

"O d d O n e, who would love to do another LED bulk-buy if the world remains functional enough...".

Yessiree....I hope so too. While I personally should wait until after the new year (unless I sell my "extra" van Monday) I'll look forward to ordering about 300. Let me know...

Hacked together a small 3 LED DC powered light last night for outside the trailer. I left the leads long so I could aim the LEDs in different directions, one at the step and one each direction on the driveway. An amazing amount of useful light for 1/3 of a watt. I have 18 watt fluorescent spots but thats more light than needed, is a bit more "advertising" than I want to do and 50X more energy than the LEDs use. Darn I love these LEDs...

-- Don Kulha (dkulha@vom.com), December 11, 1999.

I got a couple of those solar charged sidewalk lights...they charge during the day and run all night....they use Yellowish colored LEDs... I took mine out of the 'torch' base that defuses the light...once your eyes adapt to them you can see across the room with one and if needed can stick in pocket to 'shut off'. Very nice and I know for the time being I have light w/ or w/out the grid. Keep in mind I'm legally blind...so if I can see with them most anyone can. Under $20.

-- Satanta (Nightlight@LED.com), December 12, 1999.

Hello all

I am the original poster and want to make a correction or two to the original post. I have indirectly received word from 2 sources (Holly Solar and theledlight.com) of the 3 LED flange base bulbs that they will light dimly on 2 alkalines, but that that is not what they were designed for. The manufacturer has no idea how long they will last because this was definitely not a design criterian. My GUESS is 2 months on 2 alkaline D cells. Not enough time left to test thoroughly, but a test with AAA could be extrapolated.

Let me again emphasize that the 2 cell power arrangement is DIM, but it is still a massive improvement over DARK. This light is just about useless unless you have fair night vision and are fully adjusted to DARK.

beej

You are right. battery operated lights like the wallmart closet light (I now have 3) do not last long at all on a set of batteries. The screw in bulb that it ships with is rated at .3 amps or 300mA. Alkaline D cells are about 15 amp hour which means the batteries will last less than 48 hours with the original bulb. With 2 alkaline cells the single LED bulb that I made draws about 2.5mA or 1/100 as much. It also puts out aout 1/100 as much light.

Flashlight bulbs do not look like the screw-in bulb in this light, but they will press in the slot and stay. Getting an LED bulb made especially for this light could greatly increase the probability of reliable service.

I do not know about the itty bitty book light but if you get the specs or part numer on the bulb I could tell you something useful. As for eye strain, depends on how many LEDs you put in it. If this is a 3 volt device, it would take a bunch.

-- tree (thetrees@bigfoot.com), December 12, 1999.

Thanks so much Ed. The bulb in one of the itty-bittys has this around the base of the bulb: 9.5V.0.3P I don't know if the 0 is a letter or number though. One of the itty bittys runs on 2 AA batteries.

The second IB's bulb I can't make out all the #'s. on. The bulb looks similar to the bulb mentioned above. This light runs on 4 AA batteries. Hope that's enough info.

You also mentioned that you MADE your LED for the WM closet lights. If I'm not that skilled, is there an LED that I can just order from that hardware company's site and screw it in? I assume I'd want to order a bulb that's similar to the one you've made that draws about 2.5mA. Is that correct? Puhlease tell me it's that easy...grin

beej

-- beej (beej@ppbbs.com), December 12, 1999.

Geez...I'm REALLY not a totally babbling idiot. It was TREE that mentioned he'd made the bulb for the WM light. Thanks for your patience guys.

beej

-- beej (beej@ppbbs.com), December 12, 1999.

Although I have multiple LEDs lights (both hacks and store-bought), I've recently played w/ a new twist - solar-powered LED lights.

You can get them from various vendors, including Malibu and Brinkmann. They're basically those little driveway lights, but are individually powered by solar cells on the top of each unit. Inside each is either 1 or 2 little surface-mount yellow LEDs, 1, 2, or 4 NiCd AA batteries, and assorted charging circuitry, and a light sensor to turn them on/off.

Generally speaking, the Malibu's need twice as many batteries (or at least they *hold* twice the batteries...) as the Brinkmann's. For example, I have a Brinkmann w/ 2 LEDs and a single AA powering them, for most of overnight - for ~$19.00. I also have a Malibu w/ a single LED, but it requires 2 AAs and doesn't seem to last nearly so long. From the innards, it looks like the Brinkmann has a voltage regulator (is that the correct term?) that allows much better efficiency.

In any case, for $20, you can have a light that will let you see at night, and that will recharge itself during the day.

I've put a pair in the lid of the nesting boxes in my chicken coop - now that we're in those short days of winter - to encourage them to lay more. And they're trouble free - since they're built tobe weatherproof.

Try 'em - you might like 'em...

Good luck.

Hugh

-- Hugh (hewiggins@mindspring.com), December 12, 1999.