| | Re: Need Electrical Help
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| (...) Let me check I understand the theory of this - you want 1.5V across the LED, which means the resistor has to take the other 7.5V. You then pick a resistor that gives you a 20mA current at that figure of 7.5V. Then you double-check the power so (...) (17 years ago, 20-Aug-07, to lugnet.trains)
| | | | Re: Need Electrical Help
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| "Jason J Railton" <j.j.railton@btinternet.com> wrote in message news:Jn2wvH.BoL@lugnet.com... *snip* (...) You are correct, In your case (assuming those LEDs are 1.5v and not your typical 2.1v variety), Vl would be 1.5v + 1.5v, or 3v So in our (...) (17 years ago, 20-Aug-07, to lugnet.trains)
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