Feel pretty daft but I had the regulator the wrong way round. The blame lies squarely on the bad datasheet for this one, if it's the bottom view of a TO-92, write it next to the pin configuration so numpties like me will see it .
I'm still getting just +16.9v from the "+18v output" when using the 15v regulator, if anyone else has built this, is that as good as I'm likely to get?
I'm still getting just +16.9v from the "+18v output" when using the 15v regulator, if anyone else has built this, is that as good as I'm likely to get?