LX200 12 (Classic) DEC Issues

[Mark]

I have a Meade LX200 12 (Classic) that appears to have a problem. The
scope is roughly 8 years old and sadly, I havent used it much in the
last few years. I recently began checking things over is anticipation
of getting some observing time and noticed the following:

When slewing using the east and west buttons on the control pad, all
seems normal. However, when slewing using the north button, the DEC
motor begins to strain and eventually quits altogether, the scope then
begins to 'rachet down' until the OTA rests on the fork assembly. I've
also noticed the keypad back tends to feel a little warm.

Has anyone seen this type of behavior?

[ALAN MCCORNACK]

Post by Mark
I have a Meade LX200 12 (Classic) that appears to have a problem. The
scope is roughly 8 years old and sadly, I havent used it much in the
last few years. I recently began checking things over is anticipation
When slewing using the east and west buttons on the control pad, all
seems normal. However, when slewing using the north button, the DEC
motor begins to strain and eventually quits altogether, the scope then
begins to 'rachet down' until the OTA rests on the fork assembly. I've
also noticed the keypad back tends to feel a little warm.
Has anyone seen this type of behavior?

I'm willing to best two things:

1. You are not running it AltAz
2. You have a bad motor or motor controller.

I'd be inclined to send it back to Meade for servicing.
I have the 10 classic, but saw a friend go thru this with his 12
classic.

***@yahoo.com

[Zyp]

Post by ALAN MCCORNACK

Post by Mark
I have a Meade LX200 12 (Classic) that appears to have a problem.
The scope is roughly 8 years old and sadly, I havent used it much in
the last few years. I recently began checking things over is
anticipation of getting some observing time and noticed the
When slewing using the east and west buttons on the control pad, all
seems normal. However, when slewing using the north button, the DEC
motor begins to strain and eventually quits altogether, the scope
then begins to 'rachet down' until the OTA rests on the fork
assembly. I've also noticed the keypad back tends to feel a little
warm.
Has anyone seen this type of behavior?

1. You are not running it AltAz
2. You have a bad motor or motor controller.
I'd be inclined to send it back to Meade for servicing.
I have the 10 classic, but saw a friend go thru this with his 12
classic.

If you send it to Meade in Irvine, don't expect to see it for at least 6
mos.

[Roger Hamlett]

Post by Zyp

Post by ALAN MCCORNACK

Post by Mark
I have a Meade LX200 12 (Classic) that appears to have a problem.
The scope is roughly 8 years old and sadly, I havent used it much in
the last few years. I recently began checking things over is
anticipation of getting some observing time and noticed the
When slewing using the east and west buttons on the control pad, all
seems normal. However, when slewing using the north button, the DEC
motor begins to strain and eventually quits altogether, the scope
then begins to 'rachet down' until the OTA rests on the fork
assembly. I've also noticed the keypad back tends to feel a little
warm.
Has anyone seen this type of behavior?

1. You are not running it AltAz
2. You have a bad motor or motor controller.
I'd be inclined to send it back to Meade for servicing.
I have the 10 classic, but saw a friend go thru this with his 12
classic.

If you send it to Meade in Irvine, don't expect to see it for at least 6
mos.

The keypad, actually has nothing to do with moving the motors. The
heat here is normal, and is just because of the internal regulator in
the unit.
Obvious question is, 'how does the tube move, by hand, with the clutch
undone'?.
Ratcheting down, sounds horrible, and if this has happened at all
often, you may have permanently damaged the gears. The gearbox on
these scopes, is 'sprung' against the main gear, and though there is a
screw that is designed to prevent it coming out too far, if this is
wrongly adjusted, and the load is really high, it will behave as you
describe. If this happens, you effectively have the gear 'grinding'
across the worm, and it _will_ cause damage. How much, depends on how
often...
Some questions apply at this point. Is anything else on the scope?.
Guide scopes?. Wiring?. Is the main ROM, the correct one for the 12",
or has it possibly been replaced?.
I'd be inclined to think that the load has changed in some way since
it was last used. The question about the controller, is because the
controller for the larger scope, had a reduced maximum slew speed, to
help avoid overloading the gears/motor. If the wrong ROM is installed,
it can cause major problems.
If you want to investigate yourself, start by just taking the cover
off the Dec gearbox. This is easy, and is achievable by almost
anybody.
<http://www.kwastronomy.com/LX200_Dec_Motor_Assy.htm>

Best Wishes