Hoffman Amplifiers Tube Amplifier Forum
Other Stuff => Electronic Projects => Topic started by: cbass on March 30, 2012, 03:58:53 pm
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Could some one point me in the right direction for making an led headlamp.I wouldn't mind having a battery pack on a cord i could stick in my pocket.I don't think i need anything near as bright as what you guys have foe bikes.But i would still like it light up real good for 50'or so.
I could use some ideas for actually mountin the thing on my nogen.
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How about my LED lights catalog page?
Links at the top and bottom of all the forum pages and all my web sites
http://www.hoffmanamps.com/MyStore/catalog/PartsLed.htm (http://www.hoffmanamps.com/MyStore/catalog/PartsLed.htm)
100's of pages of light build info on my web site.
I even stock the elastic headlamp band that the lights mount to
(http://www.hoffmanamps.com/MyStore/catalog/images/IMG_6205.jpg)
And the light output looks like this
(http://www.el34world.com/Misc/bike/images/MarwiXML.gif)
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Don't know how I missed the headshot.I had looked over that page.
Is there a way to cut the current the LEd draws to make the light more dim and the battery last longer?
I know LEDs run cool but is there any problem with heat being against your head?
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You use driver boards to control the current/light output level
The smart board that I am out of can set the LED to 5 different current levels with just a tap of the power switch.
(http://www.hoffmanamps.com/MyStore/catalog/images/IMG_6672.jpg)
The dumb boards I have can be set manually at a certain current level.
(http://www.hoffmanamps.com/MyStore/catalog/images/IMG_2347.jpg)
These high powered LED's do not run cool.
They are running huge amounts of current and require heat sinks inside the lights that transfer the heat to the outer skin of the light body.
The head heat from the light is not a problem, but you would not want to run the light on high unless you have air moving across the surface of the light to keep it cool
The head shot band around your head is hotter than the heat from the LED.
I like to wear the Headshots over the top of a ball cap or some other hat
I only switch mine to high when going downhill on the bike.
Most the time 25% power is more than enough for slo-mo activities
There are links next to all the parts on my catalog page that take you to the main info page for more detailed build info
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Thanks a lot. I had looked over your stuff and just wasn't sure where to start.
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This page is the library of info for all the LED stuff I do
http://www.el34world.com/Misc/bike/BikesLights1.htm (http://www.el34world.com/Misc/bike/BikesLights1.htm)
There's 100 pages of stuff linked off of the page above
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Cbass, you really do not have to worry about the heat. It pretty much stays in the light housing. The bracket stays cool - at least it does on mine. Battery life is fantastic. How long do you expect to keep it on?
Jim
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If you only need 2 hours max light and you don't need to run it on high the whole time, you could get away with a two x 18650 battery pack.
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2 hours would be good enough though would be nice if I could get closer to four.I just need it to last long enough to gig my limit of frogs or find my way to fishin hole.I doubt I would ever need to use it on high.
Might come in handy at work too.When I have to get in an attic or crawl space.
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Do a four battery pack like I build for the bike lights
You can get 3+ hours on full high with 4 cells
The Li-On batteries I sell are cheap enough and 2600 mah hours each
So if you ran a light at 2.6 amps, you would get 1 hours light out of a 2600mah battery
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lots of stuff on Instructables web-site too
POWER LEDs do NOT run cool! They run from warm to hot!
use PWM to vary intensity and extend battery life