Well, it seems there’s no actual light meter on the FED 3, at least without being a wizard. Fortunately I had bought a light metre app for the iPhone so wherever I go with the FED 3(b) I’ll have to make sure I bring my iPhone along to judge the light until I master the dark art. Pun intended, sorry.
In the mean time, here’s an interesting article about said dark art: Fred Parker’s ‘Ultimate Exposure Computer’.
Here’s another FED 3 users manual here with photos of the original document and translations off to the side.