Something I remembered last night - I have recently seen somewhere (probably a
trade journel, maybe "Machine Design"????) that a blue LED is now available. 
"So what"  you say?  Well, if you bunch blue, green and red  LEDs together and
they are reasonably matched in output you get WHITE light!!!  In fact I
remember that was pointed out in the article as an option.  Now if I could
remember WHO manufactured this  . . . .

As for Cetin's polite correction (to which I take no offense):

>2)  BUT !!!!!!!  I vaguely recall from a class taken almost 30 years ago - 
>that the current draw of the diode at applied voltages above the device
design
>point (apparently 2.5 volts in this case) is only limited by the value of the
>series resistor, so you want to define the conditions you want at the diode

*Yes, for ideal diodes.

What can I say,  it was an undergraduate class and we all know the "delta"
between "class room"  and the "real world".   I'm modestly amazed that I
remembered what I could!  :-)

Harvey

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