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Old Dec 01, 2006, 03:16 PM
green-boat is offline
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Boats on the brain!!
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The bulbs in my set don't have a lip on the bottom of the LED. Between that and the bulb shape, it would make it easy to chuck th bulb up in a lathe and cut some ridges in the sides.
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Old Dec 01, 2006, 04:06 PM
not_in_houston is offline
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I did some looking and found this is probably a "Bethlehem Lighting Indoor/Outdoor 50-Lamp 5mm Wide-Angle LED Lighting Set".

They are also available at Amazon:
Multi-color
http://www.amazon.com/dp/B000F54934
Red:
http://www.amazon.com/dp/B000F54952
Green:
http://www.amazon.com/dp/B000F5494S
They're out of clear:
http://www.amazon.com/dp/B000F50W7G/

Here's the manufacturer's website - they don't have much data:
http://www.bethlehem-lights.com/lights.htm#LED

Looks really cool! Might have to get a set for the tree and another for the boat!
Last edited by not_in_houston; Dec 01, 2006 at 04:36 PM.
Old Dec 07, 2006, 10:52 PM
Umi_Ryuzuki is offline
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Sea Dragon-Lover
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Do some testing before you mount anything to a boat.

The White, Blue, and Green LED are 4volt.
The Yellow, Red, and Orange LED are 3 volt.

I set up a 4.05 volt power supply, and all fo the yellow, red, and green LED failed.

Old Dec 08, 2006, 12:07 AM
green-boat is offline
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Boats on the brain!!
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Quote:
Originally Posted by Umi_Ryuzuki
I set up a 4.05 volt power supply, and all fo the yellow, red, and green LED failed.

Sizzle, sizzle, fry, smoke, oh sheet.
Old Dec 08, 2006, 12:19 AM
MILLERTIME is online now
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Taking care of the pond.
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Quote:
Originally Posted by MILLERTIME
Look here.
LED calculator
http://led.linear1.org/1led.wiz


Don M.
Umi did you miss this?
Old Dec 08, 2006, 12:22 AM
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Taking care of the pond.
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LED basics
http://led.linear1.org/why-do-i-need...r-with-an-led/

Don M.
Old Dec 08, 2006, 12:26 AM
Umi_Ryuzuki is offline
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Sea Dragon-Lover
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Quote:
Originally Posted by MILLERTIME
Quote:
Originally Posted by Originally Posted by MILLERTIME
Look here.
LED calculator
http://led.linear1.org/1led.wiz


Don M.
Umi did you miss this?
Yeah, but the instructions say 4volt LED.
So I would have put 4 in for the forward voltage...
Last edited by Umi_Ryuzuki; Dec 08, 2006 at 03:01 AM.
Old Dec 09, 2006, 11:29 AM
jerryj98501 is online now
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You might try the following website, sorry but I just found his card again. I met Tim Anderson at a model railroad show and he has lots of information on his site on led's. You can contact him with questions but he has a lot of information on his site also. The site is www.ngineering.com. Jerry J
Last edited by jerryj98501; Dec 09, 2006 at 11:34 AM.
Old Dec 10, 2006, 12:14 AM
Milesc is offline
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Forward voltage will turn on the LED; you can have a reverse voltage in some apps but no greater then 3 to 5 volts. Led should always have a resistor placed in the circuit. Silicon type LEDs need as little as .7 volts and gallium arsenide and gallium phosphide types need 1.6 volts.
+V = supply voltage - Vf = LED forward voltage / If LED forward current
+V-Vf
If
Old Dec 11, 2006, 08:44 PM
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I'd appreciate some advice on utilizing LEDs on a model cabin cruiser. I would like to use a Radio Shack 5mm 2.6 VDC 28 mA 10 mcd red LED for the port navigation light, powered by a 1.5 V AAA or AA battery. I would use a Radio Shack 5mm 2.1 VDC 25mA 6.3 mcd green LED for the starboard nav light, powered by another, separate 1.5 V battery. I would have the remaining wiring and electronic components (motor, receiver, switches) completely separate from the above lights.
I know that this is a very unsophisticated, perhaps inefficient setup, but (1) it adheres to the KISS principle and (2) I can understand it and implement it.
Questions: Will it work? Will the LEDs that it lights last a while? (If they're not really bright, that's alright with me; I'd prefer longer LED life to extreme brightness.)
Or, would I be better off trying to find (higher voltage) grain-of-wheat bulbs for the nav lights?
Thanks all.
Bill
Old Dec 11, 2006, 09:03 PM
green-boat is offline
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Boats on the brain!!
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Trying to drive a 2+ volt LED with a 1.5 volt battery would not work very well, very dim if anything. You would have to start with 3 volts and use a resistor to drop the voltage and limit the current. LED's are very rugged and are designed to last 10,000+ hours at rated levels if they are not overdriven.

(battery voltage- LED's forward voltage) divided by LED's current = resistor value
Old Dec 11, 2006, 09:24 PM
jeepers1940 is offline
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Hello Green-boat,
Thank you for your advice. Another question that I have is whether any precautions need to be taken when soldering wires to the conducting "legs" of the LED? Will the heat of the soldering iron harm the LED? Will the soldering iron generate a small current that could burn out the LED during soldering?
Thanks again,
Bill
Old Dec 11, 2006, 09:39 PM
patmat2350 is offline
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RingTheBellsThatStillCanR ing
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Solder very quickly... but if worried, put an alligator clip or purpose-made heat sink on the leg.

Pat M
Old Dec 11, 2006, 09:48 PM
green-boat is offline
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Boats on the brain!!
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Too much heat will destroy an LED. I use a 30 watt iron and have no problem but then I have been soldering stuff together for 30+ years now. Have you soldered anything together before, if not I would suggest some practice. Irons don't generate any currents but there are grounded and ungrounded irons. If you are working with static sensitive components then grounded irons are mandatory. Do keep in mind that LED's are polarity sensitive, meaning that the + and - must be connected correctly if the LED is going to work.
Old Dec 11, 2006, 10:21 PM
jeepers1940 is offline
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Yes, I have in the past soldered small electrical components successfully - small incandescent light bulbs, wires, small switches, small motors - but have never fooled with LEDs and their idiosyncracies. Yep, I know to use rosin-core solder on electronics; acid core is verboten.
Bill


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