None of the taps are really labelled clearly, but I can kind of guess based on the configuration in the schematic, but I would feel a lot better if there was a way I could power up the transformer and check that I have the right taps, before I apply power to the completed circuit. Does it matter which line (excepting ground) comes from the input power socket and goes to the fuse? Intuition tells me no, but can't hurt to ask...there are two configurations shown, one in the layout and another in the pics...
Good you asked, your intuition is wrong. AC wiring has Hot/Line, Neutral and Ground/Earth wires. The fuse and switch should always be connected to the HOT/LIVE side of the power cord.
http://www.electronics2000.co.uk/pin-out/iec.phpIn the U.S. it is commonly refered to as Hot, Neutral, Ground, and in Europe and much of the world the IEC convention (Line, Neutral, Earth). Note Nik uses L, N, E as abbreviations.
It is wired correctly in Nik's pictures AND labelled correctly in Nik' layout, but the orientation is different between the two. Layouts cut corners, simplify things, and omit details –– assumptions are always made that the builder knows some industry standards and best practices.
As for the transformer taps...if it's like the one pictured below...you have two 120V solder tabs, two 6.3V solder tabs, and two 135V solder tabs. Ignore the "0"s, these windings are NOT polarized. It doesn't matter which 120V tab is connected to the Neutral pin on the IEC or which is connect to the Switch; it doesn't matter which 6.3V tab is connected to F1 or which to F2; etc.
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