David Drummond wrote in a message to Jasen Betts:

 DD> Al salaam a'alaykum Jasen

 DD> 14 Dec 03 09:35, Jasen Betts wrote to David Drummond:

 DD>> How do you achieve the -12V? You'd have to set up your 12 volters
 DD>> to produce 24V overall, with the centre tap as zero...

 JB> nah, get ten of them in series and feed 120V DC into the power socket 
 JB> of the powersupply.

 DD> Does a switchmode supply not need an AC source (as in is it somehow
 DD> locked to the frequency of the mains)?

Nope.

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