Ensure that the motor cables are correctly seated. 

Check the power supply and the power cable. A weak supply or a long power 

cable with too small a conductor diameter will cause the voltage to drop under 

load. The power supply and cable must deliver at least 3 amperes of continuous 

current at 12 to 18 volts. A higher voltage within the range will produce more 

torque. A regulated power supply or a battery is recommended.  

Make sure that the telescope is balanced correctly. Making the RA axis 

slightly

heavier to the east ensures that the worm is in good contact with the worm gear as 

it drives forward. 

Reduce both the manual and the GoTo slewing speed for heavy loads. 

7.1.5  UTC Date or Time Setting Wrong 

If you are located west of Greenwich England at positive longitudes (such as the 

American continent), your local time is behind UTC (or GMT).  In America, you 

must set Gemini's timezone setting to GMT x (x is between 5 and 9 hours 

depending on the timezone). To calculate the UTC time, you will have to add 

these hours. If you do this in the evening, you probably will have to advance the 

date, too.  There is a web page at 

https://cgi.tfh 

berlin.de/~goerlich//utcdate.php

that will show you the current UTC in the correct 

format for Gemini. 

East of Greenwich at negative longitudes (such as Australia), you have to subtract 

the timezone value from the local time to get the UTC time. 

If you use a planetarium program like TheSky, be sure to set the timezone 

correctly before you set date and time. This is very important, since these 

programs send the civil time to Gemini, and the timezone value is needed to 

calculate the UTC time that Gemini needs. 

7.1.6  GoTo Position is Completely Wrong 

UTC Date/Time, Mount Type and Geographic Location must be set correctly. Be 

sure to Cold Start the mount after changing these settings, or set them during the 

startup procedure of the Cold start. 

Be sure to correctly identify the objects you use for alignments.  Misidentification 

of the first alignment star will result in a wrong GoTo position. 

7.1.7  Poor Pointing Accuracy 

Make sure your mount is polar aligned within a few degrees of the pole.  

Accuracy is impossible if the mount is not accurately polar aligned and no 

Additional Alignments have been done. Select some of the Bright Stars in the 

Alignment menu, center them, and do an   Additional Align.   With the alignment 

of each object, accuracy should improve. 

Inaccuracy in GoTo operation can occur if you did a meridian flip and have not 

yet done an Additional Align on this side of the meridian.  Gear play and mirror 

flop are taken into account after the first   Additional Align   on this side of the 

meridian is done. 

Gemini Users Manual 

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