AUTOSTAR not finding North??

[Fastsky]

Hi, I have a Meade DS-2080 with the AUTOSTAR. When it starts to calculate North after finding level the telescope just keeps spinning in circles and doesn't stop. I have replaced the 8 batteries but other than the speed increasing it hasn't made any difference. Has any one heard of this problem before??

[Capricorn]

Quite possible if North is found by a magnetism and not GPS.

Part way up Vancouver island is an area where a compass reads North, close to NNE, then goes nuts and swears that you are travelling South West, this goes on for about 15-20 miles then stops.

Simply depends on the rock composition that you are on, if they have iron in them then they pick up magnetism and the earths movement reorientates them. So you get a different local reading for North.

There quite a few of these outcrops but car compasses didn't really take off, the hire car I had just happened to have one in it, and GPS has arrived and should be independant.

If you can locate a map of the earths magnetic fields you will find that there are quite a few seperate magnetic fields at a local level, not just the "normal" North Pole and South Pole. Makes you wonder how a compass ever made sense to navigators.

I can only assume that the Meade scope uses an inbuilt magnetic type compass and where you are getting conflicting results thst cannot be interpreted.

Is it possible to override the scope and tell it North manually?

[Fastsky]

Hi, thankx for the reply. I will try another location and see if it works there. Will also check if it can be selected manually.

[michael8554]

Borrow a compass and place it close to the telescope.

If it gives a reliable steady reading and points to where north should be, then local magnetic anomolies is not your problem.

The endless rotation may be due to "motor runaway", so try the "Train Drives" option in the autostar menu.

The Meade should have "hard stops" that physically prevent it rotating endlessly.

In the handbook should be instructions on how to manually rotate in RA to a setup position between the stops.

If the stops can't be felt then they may be broken off, and the internal wiring damaged by too much rotation.