LED Flashlight Infogreenspun.com : LUSENET : TimeBomb 2000 (Y2000) : One Thread
Does anybody have information about making the LED flashlights that everybody is talking about. Should be simple enough but not sure if a resistor is needed or not. Your help is greatly appreciated.
-- bil (firstname.lastname@example.org), February 12, 1999
Yes. Go back to WRP111 thread. read it it has the information you want.
-- Paladin (HaveGun@WillTravel.com), February 12, 1999.
Paladin ....Thanks for the info but I went to that link and it said issue 106 had details but issue 106 is not available to web access...members only and I can't afford to sub to another list or mag. Thanks anyway though.
-- bill (email@example.com), February 12, 1999.
Bil:: It's here somewhere, filed geologically. I HOPE to spend some time with the spousal unit in geting some of the strata cleared out. HOPE to find my copy of 106, because my local Tandy Leather - - err Rad Shack didn't have a clue when I asked about white LED's. And I mean NOT A CLUE Looked at me like I had just grown a 3rd (short) arm out of the top of my head...... Course, I probably qualified as a ..... head anyway.
PS Any other subscriber with a better filing system- you are welcome to beat me to posting the info!!
-- Chuck, night driver (firstname.lastname@example.org), February 12, 1999.
My sister sent me some info on a new windup flashlight, works like the BayGen radio. It's called the Dynamo flashlight. It sells for around $13-15. Here's their phone number: (510) 558-0700 The company is called "Real Goods," which is based in Ukiah, CA, but has a store in Berkeley, CA. My sister ordered two of them.
-- bardou (email@example.com), February 12, 1999.
WRP#106 is here: http://www.sonnet.co.uk/muse/dcwrp.html
But information on building the led flashlight is not in the online version.
-- Hallyx (Hallyx@aol.com), February 12, 1999.
The info is in WR 111. Just drop down four posts and click on the hotlink contained therein.
-- Vic (Roadrunner@compliant.com), February 12, 1999.
Would it be possible to combine equal amounts of red, blue, and green LED's to produce white light?
BTW, before there was kerosene, what kind of oil was used in lamps? I know that they used whale oil in the 19th century. What I really want to know is if there are any common household items that can be used in a simple oil burning lamp.
-- Joe O (firstname.lastname@example.org), February 12, 1999.
Yes, olive oil burns nicely in lamps with the correct kind of wick.
However, I would be *eating* the olive oil not burning it. Kerosene is TOO cheap in comparrison.
- Got wicks?
-- Greybear (email@example.com), February 12, 1999.
Hi Bill! Here are three urls that I found using 'ASK JEEVES'...Your main chore will be finding a 'white' LED. Radio Shack was no help, a local industrial electronic supplier said they could order them if I knew the size. One of the url 'build-it-yourself' articles is very interesting in that you put the LED into a regular flashlight bulb along with the small dropping resistor. No other modifications to your flashlight are required. The other construction articles are mainly for backyard stargazing/night-time map reading, etc. Hope this helps, and keep us posted if you find a source for white high intensity leds.
http://www.skypub.com/tips/projects/redlight.html http://www.intelligentchild.com/flashlight/ http://www.pitzer.edu/~jbecker/archives/ledlight.htm
\/\/illis in OKC, OK 02/12/1999
-- Willis (BANDIT1@ontheroad.com), February 12, 1999.
These sites may be of interest.
-- Tony Power (firstname.lastname@example.org), February 12, 1999.
OK, the reason the flashlight article is only in the print version is it includes drawings. Get the big Radio Shack Yellow LED, 6,000 MCD, runs on about 1.8VDC (IIRC). Put 47 ohms in series and it will run off 2 alkaline cells. If you break out the glass of a PR2, you can solder the LED and resistor into it. The LED flows current only one way.
The White LED's I've seen take 4 volts or so. 2 Cells, 3 volts won't fire them. That's why the $45 white LED flashlight uses 3 cells.
The 12,000 MCD, millicandella, light of 12 candles, is really very orange. You won't like the light. The yellow isn't bad. Also it's only 12 candles where the lens focuses the light.
I think the white's are not as bright as the orange and yellows.
-- cory (email@example.com), February 12, 1999.
Haven't had but a moment to think about this, but isn't the voltage drop across a diode .6 volts? Two nicad's make up 2.4 volts, add a diode and you have 1.8 volts. Then hook in the LED's. Off the top of my head, but I would think it should work OK. Maybe I'll give it a try next weekend and let you know.
-- Paul Davis (firstname.lastname@example.org), February 16, 1999.