Need GEM gouge

I need a good tutorial on GEM's. Anybody got a quick link to a good read?

Thanks and clear skies,

Tom (dob driver)

GEMs or GEM Forks are just alt-az mounts pointed at the North Celestial Pole to track objects with single motion in Right Ascension (RA). Accordingly, altitude motion becomes "Declination".

See this Celestron tutorial on polar alignment for the basic concepts, noting that super precise polar alignment is not necessary for general GEM use:

http://www.celestron.com/polar.htm