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tCMetaLFReaK
05-31-2006, 01:49 PM
What size resistor do I need for two interior LEDs?
mafiamike
05-31-2006, 04:05 PM
I'd say, your best bet is to get LEDs with built in resistors.
tCMetaLFReaK
05-31-2006, 04:38 PM
Got a site? :D
superwhite06
05-31-2006, 05:50 PM
superbrightleds.com
tCMetaLFReaK
05-31-2006, 05:55 PM
I checked there. Oznium is cheaper (even with shipping)!
superwhite06
05-31-2006, 06:00 PM
what kind of LEDs are you looking for? 194 type bulbs or just single loose LEDs with resistors?
tCMetaLFReaK
05-31-2006, 06:09 PM
Loose, I already replaced my interior lights.
superwhite06
05-31-2006, 06:13 PM
oh then look on Ebay, I got a package of 25 Blue LEDs from Hong Kong with resistors on them already for like $25, you can find them cheaper though. Just search for 12V ready LEDs
Sciko Hubby
05-31-2006, 06:39 PM
You might also try the local Radio Shack. They have some too.
tCMetaLFReaK
05-31-2006, 07:49 PM
I bought those LEDs I mentioned from radioshack, but I don't think they have resistors attached.

edit for link

http://www.radioshack.com/product/index.jsp?productId=2062548&cp=2032058&pg=2&f=Taxonomy%2FRSK%2F2032058&categoryId=2032058&kw=red+led&kwCatId=2032058&parentPage=search
superwhite06
05-31-2006, 07:52 PM
no, the LEDs from RS do no thave resistors attached, you have to buy the resistors and attach them yourself.
tCMetaLFReaK
05-31-2006, 07:55 PM
which brings back the original question... what kind of resistors? lol
WhiteBlazer01
06-17-2006, 03:29 AM
okay, to figure out what kind of resistor you need, you need to a few things:

- how many leds are going to be wired in parallel/series
- what color the led's are (white & blue require approx. 3.3V, red & yellow require approx. 2.0V)
- what the source voltage is.

For example: 1 blue LED needs a 470ohm resistor for a 12V application. 1 Red LED needs 560ohms for a 12V application.
tCMetaLFReaK
06-17-2006, 11:07 AM
pretty much wanting to light my cup holders.
tCMetaLFReaK
06-19-2006, 01:24 PM
http://s55.photobucket.com/albums/g146/tcmetalfreak/lights/ Instead of cathodes and LEDs
WhiteBlazer01
06-19-2006, 11:26 PM
Oh, those are the strips. I am working on universal LED's. They are pre-wired for 12V applications, and can be put anywhere. I will post pics and pricing later on.
midnightxb
06-23-2006, 11:18 PM
i'd like to my whole dash in my xb how much do you think that would cost?
engifineer
07-12-2006, 07:48 PM
The resistance depends on the LEDs rated voltage and how much current you are applying. The voltage is dependent on the type of led and the color.

For example, typical blue LEDs have a typical forward voltage of about 3.2V. Most have a max rating of about 30mA for a 350mcd or so LED. So to produce nice, safe, output I would run them at no more than 15mA in this example. A diode is a constant voltage device. With the car running and using 13.4V as your source:

13.4V - 3.2V = 10.2V left to drop across your resistor.

Now, if you want 15mA: V = IR --> .(.015)R = 10.2

So R = 680 ohms

Always figure for the running voltage of the car, not 12V. This ensures that the max current you figure for will indeed be the max current.

Hope this helps.
WhiteBlazer01
07-12-2006, 09:22 PM
i'd like to my whole dash in my xb how much do you think that would cost?

$60 for xb's. Here is my thread for LED mods for scikotics members. http://www.scikotics.com/viewtopic.php?p=38748#38748
froubaby
07-12-2006, 09:52 PM
If you're looking to do cup holders and little places here and there, we have a GB on all VARAD products including their interior lighting kit which comes with 4 LEDs.

http://www.scikotics.com/viewtopic.php?t=1093

It might not beat some of the eBay prices out there, but at least you know who you're buying from and there's a known manufacturer name (with a warranty) behind your purchase.

Thanks,
Liz