From: stoatgobbler@minasmorgul.demon.co.uk   
      
   Hi there,   
      
   I'm building a JL Hood hifi amplifier and to construct the power   
   supplies I've mounted two toroidal transformers in a case, one on top of   
   the other. Each toroid has two secondary windings which I'm going to use   
   to create two separate, independent, regulated +22v - 0 - -22v power   
   supplies. To make these power supplies truly independent (and to reduce   
   the chances of earth loop hum) I've "lifted" each power supply 0v common   
   from the chassis earth via 60ohm resistors.   
      
   On testing the power supplies I've noticed that the greater the current   
   I pull out of each power supply the greater the potential difference   
   that appears across the 60ohm resistor (chassis earth to power supply 0v   
   line). when I pull 1.1A from the power supply then I have nearly 17v   
   across the 60ohm resistor. This voltage does not seem to vary with   
   raising the upper toroidal away from the lower so I don't think the size   
   of this voltage is to do with interactions between the two (but would   
   stand to be corrected).   
      
   I've never "played" with this, I did expect a voltage across it (due to   
   eddy currents within the transformer normally "lost" in heating the iron   
   core in a conventional E I type transformer?) but I thought toroidals   
   minimised this and the voltages resulting from this would be   
   nominal....17v across 60ohm is not nominal.   
      
   Is this normal or is something going on?   
      
   Any advice or comments would be appreciated.   
      
   Stoat   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)