Can't seem to find any 1, 2, or 3 ohm resistors

Orion

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Can\'t seem to find any 1, 2, or 3 ohm resistors

Does anyone have some? I have a 3D and a 3C LS flashlights that need some resistance, but all I can get is 10 ohms at the lowest. Anyone have a few extra?

Thanks!
 

lambda

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Re: Can\'t seem to find any 1, 2, or 3 ohm resistors

Orion,

I've got 1.0, 3.3, and 3.9 1/2 watt resistors; how many do you want?

Lambda
 

BugLightGeek

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Re: Can\'t seem to find any 1, 2, or 3 ohm resistors

1/2 watt? wouldn't that be quite a bit of overkill? (I'm probably wrong since I'm just learning this stuff) But, I thought that 1/4 watt would be more than enough and even 1/8 watt would be acceptable as well.
confused.gif


Also, Orion, check out this page. I just ordered some 15, 33 & 68 Ohm resistors from them and they have the amounts you're looking for.
 

lambda

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Re: Can\'t seem to find any 1, 2, or 3 ohm resistors

Originally posted by ChrisM:
[QB]1/2 watt? wouldn't that be quite a bit of overkill? (I'm probably wrong since I'm just learning this stuff) But, I thought that 1/4 watt would be more than enough and even 1/8 watt would be acceptable as well.
confused.gif

QB]
<font size="2" face="Verdana, Arial">ChrisM,

A 1 ohm resistor passing 1 amp generates 1 watt. It may be necessary to combine three 3 ohm together to make a one ohm resistor capable of handling the power requirements for high currents.
 

BugLightGeek

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Re: Can\'t seem to find any 1, 2, or 3 ohm resistors

But, this is for what kind of application? 1AA & 2N's? 3D's?

Is it enough to protect 1-3 5mm LED's in varying flashlight mods? Is it enough to protect 1 or 2 LS LED's?

like I said...just learning this electrical stuff
smile.gif
 

Orion

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Re: Can\'t seem to find any 1, 2, or 3 ohm resistors

Thanks, Lambda! I could use a supply of about 4 of the 3.3 ohm. Perhaps about 8 of the 1 ohm.

A quick question. If you series one 3.3 ohm resistor with a 1 ohm resistor, does that mean you have 4.3 ohms of resistance? Is it that simple?
 

sunspot

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Re: Can\'t seem to find any 1, 2, or 3 ohm resistors

Yes. It is that simple for series. Parallel is not simple for a beginner.
 

Jonathan

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Re: Can\'t seem to find any 1, 2, or 3 ohm resistors

Parallel is just as simple if you think in terms of conductance rather than resistance.

Conductance is simply the inverse of resistance, and is numerically 1/Resistance. The unit of conductance is the 'Siemens', but you can just think of it as '1/Ohm'.

A 1 Ohm resistance is also a 1 Siemens conductor.
A 2 Ohm resistance is also a 1/2 Siemens conductor.
A 0.1 Ohm resistance is a 10 Siemens conductor.
etc.

As above, for series resistors, the resistance simply adds up, but parallel resistors are more complex. For parallel conductors, the conductance simply adds up, and series conductors are more complex. But you can convert between resistance and conductance simply by taking the inverse, so both are easy
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So a 2 ohm resistor in parallel with a 1 ohm resistor is the same as a 0.5 siemens conductor in parallel with a 1 siemens conductor, which gives a total of 1.5 siemens conductance. This conductance is the same as a 1/1.5 or 0.667 ohm resistance.

-Jon
 

KenBar

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Jan 24, 2001
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Re: Can\'t seem to find any 1, 2, or 3 ohm resistors

Here is one of a gazillion online helps.
It has most of your formulas...including the series/parallel resistance..plus a calculator at the top.
http://www.ejelectrical.com.au/formulas.html

If this is of use..or interest to you...


Do an online search GOOGLE.COM
GOogle

and enter "electrical resistance calculator"


If your computer has Java turned on...there are all sort of helps out there for both the ultra novice ( me ) to total bit heads.
Good luck
 
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