On Thu, 15 Feb 2007 09:19:26 -0500, "HK" wrote:



FYI, we're building a small airboat. There are four 3v LED lights
powered
by 2 "C" batteries and a single 6v motor powered by 4 "C" batteries.


You do know that LED's must be wired in series with a resistor to make
them glow, right?

I hooked them up in parallel and they seem to work just fine. Incredibly
bright too.


LEDs in parallel with each other? It's unlikely that all would light,
since the threshold voltages would be slightly different, and the one
that's lowest would prevent the others from lighting.

As someone said earlier, your LEDs probably are actually LED modules,
and come with built-in resistors. You have a separate resistor in
series with each LED.

Modern LEDs can appear very bright. I noticed that with the holiday
lights I had this year (yes, I know that's "last year", but it is
still less than 2 months ago). Those LEDs look brighter than the
miniature incandescent's.
--
Mark Lloyd
http://notstupid.laughingsquid.com

"Unlike biological evolution. 'intelligent design' is
not a genuine scientific theory and, therefore, has
no place in the curriculum of our nation's public
school classes." -- Ted Kennedy