PDA

View Full Version here: : LX200: Perfect one minute, dead the next


rogerg
21-04-2010, 08:39 AM
:sad::sad:

I had been really enjoying the last 4 nights of astronomy, after having what was a solid 2 month break and practically a 6-9 month break from it. I was unenthused, and didn't have the time. Now I'm enthused and had made the time for it.

The LX200 was working great. Great goto accuracy, smooth slews, ... just nice.

Then, last night, at 10:30ish I posted a message about photo's taken with the Megrez setup.... at 10:31ish, litterally seconds after posting that message, CCDCommand returns that the pointing of the LX200 is off by greater than 3 arc minutes. Odd I thought, I'd never seen that error before.

Within 2 minutes I had worked out what's going on - the RA motor is dead. No life.

Symptoms:
- before turning the LX200 off, it was alive in goto and DEC movements but RA was not moving anywhere.
- amp meter is reading a couple of bars lower than usual
- then after turning it off, turning it on it won't get past the "Meade" start up screen on he hand controller.

Doh!!! argh!!! why! why!!!

It was only 2007 I went through the whole drama of 9 months down-time due to lightning strike :( :( :(

Now I need to some how source spares and fix it again :( :(

I have a spare set of components for the scope, but they are not yet 100% working from the last problem :(

One thing after the other isn't it?

Oh well, guess I'll be doing some diagnosis today - replace cmos battery, test input voltage, shake the motor around a little, then ring Don @ BINTEL.

:(

PS. Clarification: LX200 classic.

h0ughy
21-04-2010, 09:28 AM
Ah yes - when i had the 12" classic version i made sure i bought a repair kit to keep just in case - which i passed on when i sold the scope. Parts are indeed hard to get. I wish you well. Maybe you could go down the mount bars and EQ mount path?

rogerg
21-04-2010, 09:47 AM
EQ alternative is on the list Hough .. tough bullet to bite, to spend the money on it though.

mick pinner
21-04-2010, 09:57 AM
hi Roger, l have a R.A drive if you need to test the scope.

rogerg
21-04-2010, 12:41 PM
Thanks Mick, will see how I go with what I have and be in contact if more spares are needed.

rogerg
23-04-2010, 08:51 PM
I just returned home with my complete spare set of LX200 parts.

News is not good for the LX200.

Swapping out the RA motor shows no improvement. It is something in the main board. My alternative main board has a known issue also.

I am 99% sure this is the end of my extremely productive LX200 as it is. I will start another thread regarding alternatives I'm considering.

Roger.

mick pinner
23-04-2010, 09:18 PM
l also have a mother board.

Barrykgerdes
24-04-2010, 09:22 AM
The old LX200 (classic) is now really past its use by date electronically although its OTA will probably still be in good condition.

I have a 10" LX200 classic that I have had since 1994. It has had a total of 4 failures of the electronics in that time however none since 1999. I have in the past been techically competent to repair the electronics and have done so for many other users.

Parts to make repairs are now almost non existant so I no longer do repairs generally and always suggest that salvaging the OTA and placing it on an EQ6 GEM will now be cheaper than a repair.

I do have a new repair kit and a few servicable parts but I like my LX200 and will not be parting with them although if I do sell the LX200 the kit will go to the successful buyer.

rogerg
24-04-2010, 09:55 AM
Thanks Barry & Mick.

Barry I completely understand. I won't be asking you to repair it, don't worry. :) And I'd be keeping spares too if I were you, just as I have, shame my spares never got fixed :)

rogerg
24-04-2010, 11:39 AM
The LX200 is working again.

To be honest I'm not sure why.

I:
1) tried a different RA motor (no luck)
2) switch xylinx chips - worked!
3) put the old RA motor back - worked!
4) put the old xylinx chip back - worked!

.... so, it's working now with exactly the same components it had a week ago when it was working. Only things have been re-seated, notably the xylinx.

I'm unsure how much I trust it. Running automated there's a risk it does dangerous stuff during the night when it breaks again. I suppose if that happens the worst that's going to happen is it'll damage it's self, leading to the same conclusion as otherwise: buy a new mount.

A new mount is still looking very attractive. But, at the same time, this was running so nicely a week ago.

Time will tell what happens next. :shrug:

Roger.

davidmck1952
30-10-2011, 01:45 PM
And I had EXACTLY the same issue a week past Wednesday at 1.45am just as Canadian studetns were shaping to come online to my CSU Remote Telescope. I have contacted you on another thread. Did you get a diagnosis from Don @ BinTel where my telescope is at present?
David

Barrykgerdes
31-10-2011, 01:45 PM
At least yours will work again but parts are near impossible to get these days. Even good S/H parts

Barry

bojan
31-10-2011, 01:53 PM
It may be a good idea to check the board for "cold joints" (and possibly broken wires on components) and re-solder it.
Also, a cleaning of IC sockets contact may help (however you did this part when re-seated them). The whole thing is probably just a bit oxidised (due to moisture condensation on board).