Mounting the hardware was a relatively straightforward affair. The BIG exception was the fact that my fork mount did not have a mounting point for the RA encoder coupler! If you lift the plastic cap off the top of the RA axis (where you see the coupler in the above photograph) you should find either a threaded hole or a small bolt head. The coupler will thread right into the threaded hole if your mount is set up that way. If you have a bolt, pull the bolt and replace it with the bolt provided by Celestron. This bolt is drilled out to accept the encoder shaft and has a lock screw in the side to hold everything together. In my case, there was neither hole or bolt under the cap.

All that I found under the cap was the end of a stainless steel shaft with a small dimple in the center. It was necessary to drill this shaft out and cut threads to accept the encoder coupler. This was not a major job once we found the parts during the Winter Star Party. The hardware store on Big Pine Key had what was needed and the job was performed with a 12v portable drill and hand turned tap.



Mounting the declination encoder requires replacing the dec trunnion assembly on the side of the scope without the dec slow motion control. The trunnion is the small dec axis assembly that screws to the tube assembly. Unscrew the fork arm from the base and the trunnion assembly from the back part of the tube and you can lift the entire fork arm off the scope. (See the base disassembly page for more information. Now remove the screw from the center of the declination circle and the trunnion assembly can be removed. Install the new trunnion and reassemble your fork arm to the scope and base. You will need to drill a couple small holes for the encoder mounting bracket. Install the encoder with the provided hardware. One warning - you will find a plastic washer on the trunnion assembly. Another washer comes with the parts kit.

ONLY INSTALL ONE WASHER! Either the new or old one is fine, but don't try to use both. I did this and the declination encoder works its way loose with 2 washers and caused me a lot of hassle before I found the cause of this.

The cables and encoders are marked to show which goes to where, but you might try hooking everything up to make sure it works before adding the dec. encoder cover. To do this during the day time, you will have to pretend you can see the stars. Set the scope to 0 degrees declination using the remaining setting circle and start the alignment procedure on the AAM. Pick out a couple alignment stars and don't worry about the WARP reading. Go to RA/DEC mode and make sure the proper numbers change when moving the scope in RA or DEC. If they do, your cabling is correct. Install the protective cover and you should be good to go!

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