For iOptron Internal Use Only
3
GEM28 Ring Gear Cover Removal: DEC
1. Use a 3.5mm hex wrench to remove 4 socket
screws on dovetail saddle. Pull the dovetail
saddle off the mount.
2. Remove three screws that hold the gear switch
cover.
Worm Play Identification and Fixing
1. After open the RA/DEC ring gear cover to
expose worm assembly and ring gear, exam
the worm assembly movement when hold and
rotating the ring gear.
(1) If the whole worm assembly moves up and
springs back down, this is normal for a
spring loaded worm/gear system
(2) If the whole worm assembly moves left/right,
or even gets free at one end, the hinge(s)
may get loose. Go to
Step 2 to Step 12
to
fix it.
(3) If only the worm itself is moving freely, the
worm end cap needs be tightened. Please
refer to
Step 13
to adjust it.
CASE (2) Adjustment
2. Remove mount motor cover.
3. Carefully unplug the motor cable from the DEC
control board.
(1)
(2)
(3)
