Separate dob mount. You remove the OTA from the mounting rings and slip it into the dob's craddle. The craddle gently squeezes the OTA in place, not directly as there is some thin neoprene foam between the two. When you want a tracking scope, you can then easily remove the OTA from the craddle and replace it into the eq.'s mounting rings.
The link below shows what I did with a mate to an 8" f/4 OTA. Something similar can easily be made for the OTA of this AstroMaster. As it is also such a compact tube, the dob mount can be made to sit on top of a table,
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http://www.iceinspace.com.au/forum/s...ad.php?t=56400
These AstroMaster scopes are actually very good. They've got plenty of favourable write-ups. And the mirrors are parabolic, not spherical, which is what you want,
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