Where to buy resistors?

Lighthouse one

Flashlight Enthusiast
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May 4, 2006
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Ephrata, Pa
Where can I get the 1 to 2 watt and 1 to 30 ohm resistors that are used to adjust current levels? Radio Shack is a waste....I'm starting to learn what works with some Led's I bought..(just new at modding)...and can direct drive some, but would like to find the resistors to experiment with. Also: Is 1 to 2 watts the correct wattage for the average mod...and will 1 to 30 ohms give me the right range to adjust current levels? Thanks for any suggestions..
 
Lighthouse one said:
Where can I get the 1 to 2 watt and 1 to 30 ohm resistors that are used to adjust current levels? Radio Shack is a waste....I'm starting to learn what works with some Led's I bought..(just new at modding)...and can direct drive some, but would like to find the resistors to experiment with. Also: Is 1 to 2 watts the correct wattage for the average mod...and will 1 to 30 ohms give me the right range to adjust current levels? Thanks for any suggestions..

Hi Lighthouse one, Two that I deal with are
MCM Electronics http://www.mcmelectronics.com/
and even better Mouser Electronics http://www.mouser.com/

There are a ton of places online. You can do a
google search for "resistors".

I can't help you out on the other questions...

Tom
 
OMG, someone from Ephrata! I don't think there is an electronic store anywhere within a 10 miles radius of the town. You might have to head to Lancaster.

BTW: I went to Clay elementary school :D

Your best bet is mouser.com or digikey.com

As for the driving the LED, it depends on which LED you're talking about.
Here's an old reference of how to Direct Drive them --->Direct Drive Reference Sheet.
 
Thanks...when I look at places like mouser...I see Minimum buy 1000 items, ect. .I get lost in their monster product lists..I also didn't see any resisters in the 1 to 10 ohm range...
I guess I just don't understand their listings. Thanks for trying to help. Can't I just run a battery direct to the LED? Isn't THAT direct drive? I hooked up a 3.7 volt li-ion to a 1 watt LED..through my meter it was reading 530 ma. IS this a safe amount for a 1 watt Led? THat baby was bright!
 
That direct drive reference sheet IS for DD with no resistors. It basically matches battery setup voltage to LEDs of certain forward voltages (Vf).

The lower the ohm level, the more wattage it needs to be. I have found in 1xRCR123 set-ups (3.7 to 4.2V fresh off charger) that 10 ohm needs 0.5W. A 2-ohm will need about 2W at 1000mA, ~1W at 400mA. If you want to tame a LuxI at 530mA, then 1w ought to do it.

If you want to run two CR123's to one LED though, you WILL need a resistor (2.7 ohm, 2.7W min at 1000mA).

See this calculator here.

I ordered a bunch of resistors for a series of mods a while ago, the high shipping cost made a large quantity buy OK, but lower quantities are very expensive. And still it was very hard to find anything under 10 ohm. I put two 10 ohm in parallel to get 5 ohm.

I still have a few 10 ohm 0.6W resistors if you can use just a couple.
 
Thanks...I'm basically trying to run several types of Led's with 18650 Li-ion batteries. Just fooling around- trying to make a home made light with parts from work. I have an aluminum tube, a star 1 watt and 3 watt and a cree. I hooked each up direct to the battery and they seem to function at various ma's under 850. The 1 watt pulled 530- so I was hoping that is safe for that LED. I don't care if I don't have a perfect set-up...just trying to figure out how things work...and if I really need a resistor- and approx what watt and ohm....for now I guess I'll just run direct off a battery..I can't locate any resistors ( less than 1000) in small quantities anywhere near what I think I need to experiment. I though about a pot...can't find that either.
 
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Digitkey sells resistors in small quantities. I think the minimum quantity is 10, but they do have a $5 handling fee for orders less than $25.
 
Lighthouse,

If you ever get to the Harrisburg area, there is an electronics store off of 19th street called Cumberland Electronics. They have a vast selection of 1 and 2 watt resistors starting in the .1 ohm range and going up from there.

IM me if you need any more info.

Z
 
Ditto, for IsaacHayes recommendation for Jameco. Good prices and a great staff. Newark.com is my more expensive and less helpful backup for Jameco.
 
If you just need a few, PM me. I have some "less than 10 ohm" resistors I can spare.
 
I have an electronics supply place that sells resistors I pass by often give me an idea what sizes you are interested in and I will get you prices.
 
I need to order some components from either digikey or mouser soon and it will be over $25; if you know what you want I could order your resisters and forward them to you.

-Mark
 
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