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 Can I use blue led's for the larson scanner kit?
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By: Anonymous: Chris () on Saturday, February 04 2012 @ 11:00 PM PST (Read 2416 times)  
Anonymous: Chris

I just got your kit but haven't started putting it together.... I was wondering if I could use blue led's for it. If so, could you give me some pointers on the type of led and what resistor values I would need (if I can even do it at all)....

Thanks so much...





       
   
By: Windell (offline) on Sunday, February 05 2012 @ 12:23 AM PST  
Windell

For blue LEDs, use the same resistor, but change from a 2xAA to a 3xAA battery holder; the blue LEDs require higher voltage.


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By: Anonymous: Chris () on Sunday, February 05 2012 @ 05:44 PM PST  
Anonymous: Chris

Thanks for your help.
I should have read the basics post first. Sorry for waiting your time....





       
   
By: Anonymous: Chris () on Sunday, February 05 2012 @ 11:12 PM PST  
Anonymous: Chris

If I were to use a pc power supply and use the 5V power cable, can I do that with the blue led's or do I need a voltage regulator?





       
   
By: Windell (offline) on Monday, February 06 2012 @ 02:59 AM PST  
Windell

From 5 V you do not need to use a regulator, but you should increase the resistor values to compensate.


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By: Anonymous: Chris () on Monday, February 06 2012 @ 10:29 AM PST  
Anonymous: Chris

Thanks. I purchased blue ones with the following spec's...

3.6V/20mA. Blue LED-5,000 mcd typical

Can you recommend the resistor value I should bump it up to?





       
   
By: Windell (offline) on Monday, February 06 2012 @ 10:43 AM PST  
Windell

A value of 50-75 ohms should work fine.


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By: Anonymous: jiyang1018 () on Friday, April 06 2012 @ 07:04 AM PDT  
Anonymous: jiyang1018

What if I want to connect to a computer PSU, 5v, and use the blue LEDs from your store, 10mm diffused blue led,
"Intensity: 1,000 mCd typ. at 20 mA
DC forward current: 30 mA
Forward voltage (typical): 2.7 V"
what type of resistors do I need?

Another question is that can I use computer power switch to control the settings on the board, and leave power on the whole time? I will put a engine start style button to turn computer on, so the original power switch is not in use.







       
   
By: Windell (offline) on Friday, April 06 2012 @ 09:53 AM PDT  
Windell

Same as above; use 50-75 ohms.


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