> Oh, and *don't* connect the LED to the 9V source at all. I did that once 
> by mistake... that particular LED doesn't do anything now.
>
> Ah, life seemed so much simpler back then. :-(

Reminds me of an interesting story.  We got a complaint from a customer that 
about 25% LCDs they have from us have a dark edge to the picture, either on 
the left or the right side.  When we checked the faulty ones we found that 
always the left or right LED was not working in the backlight (I think there 
were 8 in total).  This puzzled us for a long time, why would it always be 
the far left or far right LED that stopped working, and why were they 
breaking in the first place?

In the end we figured out what happened.  Actually *every* LCD we shipped 
had one broken LED, it's just they never noticed it when it was one of the 
central LEDs.  And it turned out the equipment at our outgoing inspection 
test was set to the wrong voltage, so the tester was just blowing one LED on 
every backlight that went out :-)

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