Gordon Wedman wrote:

Sure, these things are cheap but try making a masthead tri-colour out of
LEDs. Current price is something like $300US compared to $6 for a halogen
version.

Regulating the voltage going up the mastehead sounds like a good idea.
Since this does not involve that much current, certainly not 40 amps, I
wonder if you could build a small voltage stabilizer using a 7812 regulator
IC for just the mast lighting circuit?



A 7812 will probably not provide a good solution because as the battery
voltage drops closer to 12V the thing will not beable to regulate
properly. I think it need about 2V about output voltage (i.e. 14v) which
your batteries will not be able to provide. A better solution would be
something with a switching regulator (see national semiconductor page).
This would be able to not only provide 12V from a fully charged battery
but also provide 12V when the battery drops below 12V. It would
require a few more components but it would also be quite easy to make
big enough to support a large current. Switching regulators are also
more efficient than standard in-line regs but if you are only looking at
the mast head light it probably doesn't matter too much.

Steve