On Fri, 26 May 2006, Michael Rigby-Jones wrote:

> This is primarily because only one of the rails is actualy regulated, 
> the others are just extra windings on the transformer.  Under the 
> minimum load conditions those rails can fall well out of spec, and the 
> the PSU will usualy shut down.

True, and the usual fix is to provide a minimal load on each. Usually 
drawing 0.2A on each is enough to make the psu behave.

Peter
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