[Elecraft] Power Supplies

[Ron D'Eau Claire]

Waste heat? Then why to linear supplies typically have NO fans while even small switchers depend upon them? 

A linear supply has only a tiny loss in the transformer. 

Both linear and switching supplies have losses associated with the voltage regulator circuits, but in that respect they are similar. 

Switchers can be highly reliable, but they have far more parts subject to failure than the typical linear supply. The advantages of a switcher is that it is lighter and smaller (thanks to avoiding the big transformer) and typically cheaper. 

In the thousands of critical commercial applications I have worked in, both on shore and at sea, linear supplies were the standard. 

But anything can and will fail over time.  

73, Ron AC7AC

-----Original Message-----
...it emits much less waste heat than any linear supply I have ever come in contact with. The waste heat issue alone is one of my primary motivations for installing a switching supply, and is an important consideration in a number of commercial systems. 
Mike Alexander - N8MSA 

amsctalx at comcast.net