> I have looked at switching regs but they seem to be not the best for
> availability and require expensive inductors etc for use. I want to build

I guess that should be "relatively expensive". I found that I could get largish
toroid inductors from Pulse for about GBP0.8 (a little over a $US1). If it was
going to save trying to dissipate 7W of heat in a hot environment I guess the
inductor is "relatively cheap".

Now it is a while since I looked at them and I do not recall if the specific
inductor I was looking at is suitable for a switching regulator, but at that
price I would have a pretty good try.

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