>7805 is still up around 8-ish volts. Probably need a 2W, you'll
> have work that out from actual current passed.
>
> HUH?  You calculated the ENTIRE dissipation is "about 0.5W"

Hi Tom,

Added a margin for wallwarts being notoriously over label voltage,
derating for high ambient, and just plain conservativism. A 1/2W
wire-wound may be OK running at 50C + Tcurrent, but another
sort (eg 1/2W metal film or carbon) may not for extended periods

If wallwart is actually 12.0V, that's 0.497W for the drop across
the regulator for starters

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