LX200 Dec Runaway

[rogerg]

Turned my LX200 classic on for the first time in a month or two on Saturday night. Instant Dec runaway :( :(

Quite disappointing, after not having used it for a little while to find that. And for this to happen 8 months after I got it working after 9 months being dead due to lightning strike. Now have to sort it out. I have leads to follow, just have to try some things and go from there. So it's not like it's a dead end, I'll work it out eventually, but just disappointing. :(

Eventually I'll have to end up putting some money aside for a new scope :whistle:

[Merlin66]

Sorry to hear that!
As you probably already know, there's solutions posted on the LX200 Yahoo forum, unfortunately not an uncommon problem.
Best of luck.

[RB]

Roger does it do it every time you turn it on?

[rogerg]

Yeap, will be digging in there, thanks.



I tried it 5 times:
1: Dec runaway
2: Dec runaway
3: un-plugged Dec motor cable, no Dec runaway (no surprise!), other functions appeared to work.
4: plugged Dec motor cable back in, Dec runaway observed again.
5: Tried again for good measure, Dec runaway.

Thanks,
Roger.

[RB]

I assume you would've tried another cable.

I only had it happen to me once a long time ago, been ok since.

[rogerg]

Not yet, I really haven't done much. I will try plugging the motor direct in to the front panel. Don't have a spare cable, but could get one locally.

Roger.

[rogerg]

Interestingly the problem has "evolved" somewhat. Turning it on tonight there's no Dec runaway. Instead, the motor is sounding decidedly "sick".

I've pulled it apart and it seems the motor was quite tight against the main cog. I wonder if it was too tight, there was some movement. Anyhow, not sure how having it too tight would have caused Dec runaway.

Have losened it all off to test the motor's functionality without load.

So at the moment I can turn it on and it's fine, if I move the NS buttons it moves in the direction but is sounding sick and slow.

I'll investigate more in the coming days. At this stage it's looking more and more like a motor issue than a main board or any other of the causes that cause runaway outside of the Dec motor assembly, which is good news to me, I'm sick of replacing main boards!

Roger.

[Ric]

Bugger, I hate to read of members scopes not behaving.

I hope you get it all sorted soon and get back to your imaging program.

Cheers

[rogerg]

The good news: My LX200 is working again. :D

The bad news: I'm down one DEC motor, thank goodness for the spare.

I'll now try to get the spare fixed (thanks to those who have PM'd me help and suggestions). I'm quite sure the problem is going to be the photo sensor in the motor. We'll see.

Roger.