> I was thinking similarly about dropping the voltage a bit before letting
> the regulator have it, but I thought of 2 regulators -- first drop to 9V
> or 8V, then the 7805.

With a linear regulator, 1.8W is going to be dissipated somewhere.  That's
too much for a single TO-220 without a heatsink.  If sufficient heat sinking
isn't possible, then you need to spread the dissipation over multiple
components.  A 9V regulator will spread the dissipation to two devices.
This approach may be required if the circuit draws large current spikes.  If
the max draw current is well known then a resistor for dropping the voltage
will be cheaper.


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