[Elecraft] LED bulbs

[Chip Stratton]

Incandescent bulbs get rid of most of their waste heat as IR radiation.
CFLs do so too, but since they are more efficient there is a bit less IR to
radiate. LEDs radiate very little waste heat, but since they are still not
perfectly efficient, their waste heat has to go somewhere, and that
somewhere is conduction into the base of the bulb and/or a heat sink near
the base. So yes LED replacement bulb bases can get pretty hot, but that is
because that is the direction the waste heat has to go. An LED which
converted all of its energy into visible light would create about 683
lumens/watt, but typical LED light bulb efficiencies are usually  around 60
lumens/watt (depending on how hard they are driven), so still not even 15%
efficient at converting power into light. Compare that to an incandescent
bulb, which offers about 10 lumens/watt.

Chip
AE5KA