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Hi Kosh.
Your Dec circles should be fixed so that when you point at the celestial equator it reads zero and at the south celestial pole it reads 90 (-90 actually). The RA circles do rotate.
To use them you need to center on a known star, find out by looking in a book or on the internet its RA coordinates, then rotate your RA circle so that the marker on your RA axis is pointing to those RA coordinates. The RA then rotate as you move your scope. The hardest part it trying to work out whether the inner numbers or the outer numbers on your RA circle represent the southern hemisphere. I can never remember, so I find out the RA for two known stars, center one then set the RA coordinates to that star (inner or outer it doesn't matter, but for this exercise let say inner ones). Then swing to the second star. If the new RA coordinates match the RA of your second star then you've selected the right ring of numbers. If it doesn't then use the other ring (outer this time). Set to your second star and then swing back to the first and its RA should match with the ring. I don't use the scope setting circles very often so I don't bother remembering which is the right ring of RA. If your going to do it regularly then place a mark on the correct ring of numbers.
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