Scope is 12.5, 9 years old. We align by going to "named star," selecting one, slewing, correcting, hitting synch. Repeating with another star. Almost always the scope goes to accurately there after. (We avoid the "align" menu which we never got to work). Now, after we align first star, scope turns erratically in circle instead of slewing to second, as if it didn't want to cross the meridian. We tried turning it off starting again, nothing works. Eventually stalls.

You should return the scope under warranty-- however a bad power supply-- and or a bad hand controller cable can cause these symptoms called a "runaway slew".

Get a separate 12 volt power supply and the proper cigarette lighter style power plug.

Once the scope has taken a GPS fix and knows TIME, and SITE, and you do a two star alignment your alignment stars overide any automatic alignment issues.

You could turn off the GPS put in Time, Date, and Site, do a two star alignment and everything would be fine. Centering the alignment stars is the "trick". Apparently the scope also finds NORTH OK, or the alignment stars would be way off. Since you pre-level the tripod already the software can FAIL on "tilt" and you still get good gotos.

I would not worry about it, especially since your gotos seem perfectly fine.

You need to synchronize the telescope with stellarium. Center the telescope on a known star, then select the same star on the laptiop and 'synch' with it.

You must set TIME, DATE, and SITE-- probably does not know your actual location. Read the manual and perform all of the setup procedures.

Some of these have a "starting position" again read the manual and make sure you are in the "home" position before you start the alignment. Read my TIP on my profile page about GOTO telescopes, and join the NEXSTAR forum on www.cloudynights.com

Start from scratch-

RESET the hand controller.

Calibrate motors using the same power source you will use outside.

Re-train the drives

Calibrate sensors on Polaris

Use either the 110 volt power cord, or buy a 12 volt power pack and the proper Meade 12 volt cable. (www.scopestuff.com carries the right 12 volt cable)

If your scope is NOT the LNT or GPS model you must level the tripod before you align. Go to home depot and buy the $3 small plastic two way bubble level, or the bulls-eye style bubble level.

Further trouble, I suggest going to the LX90 Yahoo group forum, and asking questions there.

Good Luck

I also have an 8i, but decided not to upgrade the controls yet. I've had my scope for about four years. I have experienced the same problem and am not sure what what causes it. Some nights, the scope tracks alignment all night, other times it does not. When the later occurs, the only thing that helps is to repeat the alignment picking new targets. One night, I had to repeat alignment 3-4 times. Also, I highly recommend a book by Michael Swanson, "The Nexstar User's Guide". It's an easy read, very specific and keeps the novice in mind. It should be included with every Nexstar sold. Go online to: http://www.Nexstarsite.com. Hope this helps. John

Be sure that the Azimuth Axis is Lock, you migth want to try and move the telescope in the Azimuth to make sure it is it is locked. Be carful not to force it. I have seen on some post where the locking part of the Azimuth somtimes breaks. and the Azimuth Axis will just spin freely Locked down or not.

Be sure that the telescope is configured for EQ SOUTH mode to tell it is in the southern hemisphere. Once a star alignment is completed NEVER manually move the telescope. Use only the control panel to slew. Everytime the telescope is move by hand, the motors do not know it has been done, and assume it is still pointing at the old direction. Check the manual for setup.
Here: http://www.celestron.com/c3/images/files/downloads/NexStar_SLT_manual.pdf

Some (not all) versions have an end stop - it it just reaching that? The scope will rotate only aboit 3 complete turns between the 2 ends.

The 'correct' starting position is as follows: Place scope on tripod or table with control panel at the West. Unlock the declination lock (horizontal slew). Rotate scope anticlockwise until it hits the end stop, Then roate it back clockwise until scope is pointing North (should be about 3/8 of a turn, as the end stop is at South West). Then lock the declination, Set the tube horizontal and continue with the alignment process.

Autostar always thinks you have set the position like that. If you haven't, it will work OK until it tries to rotate past the point it won't go, then chaos results!

A low voltage power supply is the usual cause. You must use fresh batteries and or a seperate 12 volt power pack.

Also you must accurately;y do all the setup-- like Time, Date, and Site properly. Read the setup in the manual again.



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