I agree Piet, it seems though that the OP might have not been careful about that. Certainly doing and "Up and Down" ALT test is invalid. I'm also a bit concerned how he relates his initial north alignment. He's aligning on Polaris, which is not true north. I'm not sure how much error that introduces at 41°N latitude. It might be enough that HP or syncs will compensate for one area of the sky but other areas will then be out. He also mentioned leveling after aligning Polaris, and it seemed to me he released the DEC clutch. Maybe I read it wrong or he related the sequence wrong, but after telling the mount you're pointing north, clutches must remain locked. I haven't had my lx200 out in a long while so it could be my confusion since I'm using a celestron GEM lately, but isolating the issue seems more confusing than it should be.
For example, the OP referenced that RA tracking is on when he selected terrestrial mode. All motors are off in that mode, and if he's in Alt-Az mode both motors are used for tracking. He reports that the drift he's seeing is purely up/down when tracking which immediately has me thinking he's put the scope HBX in polar RA/DEC mode while using it in ALT-AZ. That would basically turn off the DEC motor tracking unless he's programmed for cone error correction and cause the symptom he described.
Perhaps the OP can clarify how he has the scope mounted what he's got set, or if he's done a factory reset to have a known starting point. It might help.
Pointing the scope at Polaris for North should make no difference for my location.. I have tried both selections when using Polaris, (TRUE & COMPASS)
The True North DEC error for me is -5 degrees; tried that too.
I've also used a compass to point north; still not good.
BTW: Polaris is within 1 degree of True North when pointing at it.
Sorry about the confusion concerning how I set up.
Yes, I've done a reset several times. Verified all info is correct.
Scope type, alt/az mode, DST, time & date.
1) Level Tripod
2) Mount scope
3) Loosen RA & DEC.
3a) Use spirit level to insure OTA is level thru 360 degrees.
4) Point North at Polaris and center w/ 9mm ep.
5) Lock RA
6) Lower scope and use spirit level on OTA to level it.
7) Lock DEC.
8) Turn power on to initialize
That's about it before I select one or 2 star alignment.
..and yes; I've done scope training w/o problem on a object a mile distant.
Not sure why you believe the "spin test" is invalid?
The Meade engineers looked at the video I made and agreed there is a problem.
From everything I've read, the readout should return to 00.00.00 or extremely close to it after starting at
level, rotating thru 360 and then coming to rest at level.
For example, the OP referenced that RA tracking is on when he selected terrestrial mode.
No. The RA "clock" is running on the HBX,, (i.e) Counting (up)...60 arc secs per min. This makes perfect sense and as it should be.
The scope is NOT moving because I did not go through the alignment procedure; I was only testing ALT/AZ motor accuracy on land objects.
He also mentioned leveling after aligning Polaris, and it seemed to me he released the DEC clutch.
Of course I released the DEC lock after pointing at Polaris.
Pointing at Polaris, in my case at 41 degrees, the OTA needs to be returned to level.
Believe me; I've tried everything, ALT/AZ and polar mode, thinking maybe the HBX was wrong.
GPS is working fine as it gets my location, time & date correct.
Also interesting to note, changing DST on or off had no effect.
One would expect to see a 15 degree difference in RA.
Also interesting, periodically (though rare), the scope would do a pretty good job pointing with precision; then on a subsequent slew, even if only
moving 20 degrees; it would miss the target by 10-15 degrees.
This ^^^ indicates to me a slipping clutch or optical shaft encoder slipping.
Edited by Blackbelt76, 29 November 2019 - 08:19 AM.