From: pallison49@gmail.com   
      
   Peter Percival wrote:   
   >   
   > What is the advantage of a four diode bridge full-wave rectifier over a   
   > two diode full-wave rectifier.  There must be some, else why accept the   
   > extra cost?   
   >   
      
   ** The extra cost accrues with the two diode rectifier - cos the larger,   
   centre tapped transformer needed increases cost more than two more diodes do.   
      
   Two diode, full wave voltage doubler supplies are also common with direct off   
   mains and transformer isolated supplies.   
      
   Two vacuum diode, full wave systems were once the norm but soon became   
   obsolete when silicon diodes appeared in the 1960s.   
      
      
      
   .... Phil   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)