LED barely lights up, resistor problem?

[Matimeo]

Thanks in advance for help on my first build. I've read through about every post in the forums and haven't seen an answer to this specific question. I was wiring up my first saber today and connected my battety pack (nimh rechargeables, 4 x aaa = 4.8V) negative wire to a 1.8ohm 5w resistor, then to the negative diode of the LED. Specs on the LED say it wants 3.2V at 900mah max. Positive wire from battery goes to my latching switch, then to the positive on the LED. I calculated the 1.8ohm resistor after using the solution found on this LED calculator: http://led.linear1.org/1led.wiz?VS=4.8;VF=3.2;ID=900 (http://led.linear1.org/1led.wiz?VS=4.8;VF=3.2;ID=900). All others get me the same solution. When I wire it up and test it, the LED barely lights up. If I take the resistor out of the circuit, it lights up very bright (I just did it for a second because I don't want to fry it). Is there something wrong with my resistor or what? Any help appreciated.

[xl97]

pick your battery pack.. and the led you have from the drop down (make sure on the resistor tab)

http://www.thecustomsabershop.com/wiringbuilder/wiring.aspx


see if gives you the same value resistor..

do you know the led type/brand/model you are using?

[Matimeo]

I think I figured it out and I feel silly. The resistors say 1.8K ohm, which I assumed was the same as 1.8 ohm. However, a few google searches seem to be indicating that 1.8K ohm is 1800 ohms. Crud! The most annoying part is I waited almost a month to get these through ebay from a seller who took his pretty time shipping them. I feel dumb.

[xl97]

LOL.. that would do it.
thats alot more resistance then needed :)


have you searched the store:
http://www.thecustomsabershop.com/Search.aspx?k=resistor

Where are you located/

maybe try ordering one from Digkey (ships fast!) or Mouser?


or maybe try contacting your local makerspace in the area.. and see if they have some you can get?

[Matimeo]

Looking much better now!

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