I'll need to dig it up, but I have used this in power supplies before.

Lee McLaren wrote:

>I remember once seeing a circuit for a triac or SCR preregulator for a
>DC power supply but can no longer find the circuit. It was in the form
>of the bridge rectifier and used and error feedback from the output of
>the final regulator so that the final regulator had a pre-set voltage
>drop to keep power dissipation down.
>
>Anyone seen such a thing?
>
>regards
>
>Lee McLaren
>  
>

-- 
  *
  |  __O    Thomas C. Sefranek   WA1RHP@ARRL.net
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