Leds

[b willow]

Hi.
I was in Wall Marts yesterday they are setting up there Christmas items
they have a good supply of led tree lights with inverted tops both clear and
in color.Dont wait till later hopping to get them at a close out price They
were all gone.Try other stores they may have other sizes both round and
inverted tops.I personally use clear leds and color them with Tamiya Color
Acrylic Paint it seems to be brighter.

Good Luck

Bob

[patmat2350]

Cool, I'm on the way!

Here's the original thread discussing those inverted tip LEDs, which do a good job putting out light AROUND the bulb instead of out the tip:
http://www.rcgroups.com/forums/showthread.php?t=603835

Only problem is that they are 5mm diameter, best on bigger scale models...

[nick_75au]

Someone over on the Mayhem site mentioned roughing up the surface of a LED will diffuse the light for a more even distribution of light. Fine sandpaper to do the roughing :)
Nick

[patmat2350]

These inverted tips are way more effective than any flatting/roughing/tip painting job I've ever been able to do. They're just so BIG...

[Umi_Ryuzuki]

I have been using standard 3mm LED...

The light is distributed well,.... once it's cast into the form I want. :o

[Kmot]

I just got back from Walmart after going with my wife to do some shopping. I thought I could score some LED lights. Well the local Wally World has not set up any Xmas stuff yet, and so no joy on the LED kits. :(

[1Ironhorse]

Pat,
Did a lot of searching and found this;

http://www.allegromicro.com/en/products/categories/sanken/leds/sel2013.pdf

I don't know how you can get small quantities, but it's a contact.

OK, I spoke to soon. Found:

Michigan
R.O. Whitesell & Associates (Allegro & Sanken Semiconductors)

(Main Office)
27333 Meadowbrook Road
Suite 120
Novi, MI 48377
Phone: (248)348-5454
Fax: (248)348-5422
Web: www.whitesell.com

5900 So. Main St.,
Suite 100
Clarkston, MI 48346-2314
Phone: (248)620-9640
Fax: (248)620-9680

7484 Main St.
Jenison, MI 49428
Phone: (616)457-1717
Fax: (616)457-2280


For those of you who live somewhere else, then look at this website for sales office in your area.

http://www.allegromicro.com/en/products/categories/sanken/leds/

Choose your location from the Sales area.

[patmat2350]

WAY cool! I was looking for the source of the 5mm LEDs, no luck, and had no idea they came out with 3's!

Hmmm, but no whites listed....

[Umi_Ryuzuki]

I buy 3mm white in batches of 100 off of e-bay.

;)

[Shaun Hendricks]

You can turn a standard 'lensed' LED into the 'inverted cone' type with a typical drill bit and a drill press or careful hand drilling in a vice.

Nice thing about this process is that it removes the 'polish' off the LED as well in the front lens and casts light more softly, simulating other styles of lights, yet leaves the side lighting ability alone. You can build specific reflectors then to match other light types and adjust it to cast whatever kind of light you want.

Umi has the right idea, buy in big lots and modify to your desire and design. I buy most of mine through Batteryspace.com as they have some great deals on the higher power ones from time to time, in any color.

[time4420]

Does anybody know how to choose what resister to use with LED's?

[wolfsong]

you can apply ohms law..
you need to know the voltage and amperage draw of the individual LED as well as the voltage you want to use (your battery voltage)

ones you know this info, you can calculate the size of resistor needed.

the rsistor needs to be soldered in series with the LED

series circuit rule :
- the total voltage in a series Circuit is the Sum of all individual voltage drops
(V-total= V1+v2+...)

- The amperage in a series Circuit is the same in the entire circuit
(A-total= A1=A2=A3...)


example:
Battery Voltage :6Volt
LED 2 Volt, 25mA

you need to drop 4 volts in a series circuit:


resistant = Voltage divided by Amps

r= 4V / 0.025A

resistor= 160Ohm

[time4420]

so a 12V source with an LED with a FV of 3.5 and a currant of 20mA would be a 600 Ohm. resister?
The LED is a square 4 prong super bright. How will I solder? To what prong?

[time4420]

12V divided by .020(20mA)=600Ohm.? Is that right?
I need to drop 8.5V.

[time4420]

superbrightleds.com has a calculater but I'm still lost.

[Umi_Ryuzuki]

This should help with resistors.
http://led.linear1.org/1led.wiz


Yellow and red
Forward Voltage 1.8v-2.2v
Forward Current 18 mA

White and Green
Forward Voltage 3.2-3.4v
Forward Current 20mA

Source voltage will be the battery or
the power supply voltage.

[time4420]

It sure did! :)
Thanks Umi.

[EMSPAUL]

Patmat2350
Here is link of the l.e.ds that we use .
http://www.nteinc.com/NET_St_lst/Disty.html
There is a list of stores in your area.
Hope this helps
Paul