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ETX CLASSIC FEEDBACK
Last updated: 30 September 2010
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This page is for comments and user feedback about ETX telescopes. ETX models discussed on this page include the ETX-60/70/80/90/105/125 (EC, AT, BB, Premier Edition). This page also includes comments and feedback of a general nature. Comments on accessories and feedback items appropriate to the ETX-90RA, DSX, and DS models are posted on other pages. If you have any comments, suggestions, questions or answers to questions posed here, e-mail them to me for posting. Please use an appropriate Subject Line on your message per the Site Email Etiquette. Thanks. Remember, tips described on this site may invalidate the warranty on your telescope or accessories. Neither the submitter nor myself are responsible for any damage caused by using any contributed tips.

Subject:	Meade Repair
Sent:	Thursday, September 30, 2010 08:39:46
From:	Larry Kendall (k5end@att.net)
I have a small Meade Maksutov-Cassegrain that I purchased around the
year 2000 that now has severe play in the declination axis. I suspect it
may have been subjected to excess torque in my absence and gears or
drive therefore damaged. The last time I used it was the Mars proximity
event in 2003 and it worked fine then.

Upon inspecting the scope I also noted a significant amount of lint on
the optics' surfaces. I did not observe dust per se, but threads of
lint. How this happened is a mystery to me, as I generally take very
good care of instruments.

My memory suggests the objective is 150 mm. However, I see on line Meade
does not make a 150, but does make a 125 scope. Right now it is packed
away and would take me a day or two to look it over.

Do you do mechanical repair, and if so can you upgrade the failed
components as well as other parts known to be prone to failure to
something more durable?

Can you clean the optics of the lint and check collimation?

I realize this may be an expensive repair, and would like some idea of
cost beforehand. I understand you cannot quote repair costs without
having seen the telescope, so I do not need firm or exact figures. Maybe
you have a refurbish-and-alignment package?

Thank you,   
Larry Kendall
Mike here: If the telescope is an ETX, which it sounds like it is not, Dr Clay Sherrod can likely repair and do the cleaning as well through his Supercharge service. You might want to contact him anyway. See the Supercharge link on the ETX Site home page.

And:

Thanks. We checked and it is an ETX-125. It also has the smart
controller for known objects; I believe it was called the Autostar.

I need to start using the intelligence of this instrument. I see you
have an ETX book on Amazon. I plan to order a copy once I know this
scope is repairable.

In years past I used an old Coulter 10" with alt-az setting circles I
made in college in the machine shop, with a Hewlett-Packard HP-41CX and
key-stroke program to convert an object's location to alt-az
coordinates. That set up was accurate to less than a degree, and was
therefore always within view of my Teleview Plossl eyepiece. This was
before GPS, so determining ones lat/long was another process and had to
be entered into the HP manually. I have no idea where that old HP
calculator is now.

So now these new telescopes will do all that work with a GPS input and
touch of a button or two. Cool.

Thanks again,
Larry

Subject:	Lunar World Record - Largest Ground Based Mosaic Image
Sent:	Thursday, September 30, 2010 07:07:45
From:	Stephen Bird (stephen.bird@btconnect.com)
I'm not sure where you might want to put this on your site, but it is
something worth seeing. Entirely imaged from the UK using amateur
telescopes and high frame rate planetary cameras it is a sight for sore
eyes.
 
Enjoy.
 
http://www.lunarworldrecord.com/
 
Regards
 
Stephen Bird

Subject:	how do we get your e-mail updates
Sent:	Tuesday, September 28, 2010 22:32:08
From:	jo3777 (jo3777@bellsouth.net)
Please send info re. getting mail updates to  jalexrua@yahoo.com
Thank you.
Mike here: See www.weasner.com/etx/site/site.html
Subject:	Broken ETX Gearboxes
Sent:	Sunday, September 26, 2010 15:14:01
From:	Andrew Johansen (johansea@optusnet.com.au)
Just saw this today
// quote//
From: Mark
To: drclay@tcworks.net
Sent: Friday, September 24, 2010 12:44 PM
Subject: Broken ETX gear assembly....

 I have an etx 125 that has broken the RA gear assembly in the base.
 The ring that fits on the worm broke off, and I have made a repair.
 My etx has the newer style tapered clutch, and I have disassembled,
 and reassembled. My question is, how tightly should the gear box be
 screwed down? When I just snug the gears box against the o rings, I
 have a lot of movement that seems to stress that arm. I am afraid to
 screw it down all the way in case it should break a mounting tab.
 What advice can you give on tolerances and such for reassembly of the
 Ra gear box/worm gear assembly? Your help is great appreciated.
// endquote//

I saw Docs answer, but would add a bit extra.
I did a complete analysis of an ETXPE RA drive system a while ago
ref http://www.weasner.com/etx/techtips/2010/Analysis_of_ETX125PE.html
Whilst the gearbox does float on ORings,
when it comes to preventing the drive arm from snapping,
the actual worm fit and preload is the more critical item.
In my diag1, i show the way the gears interact with a simple force diagram.
If the worm has too much preload on its endplay
( ie the thrust bearings are simply friction plates ),
or it is jammed against the worm wheel too tightly,
you will need a high torque to get the worm turning.
The higher this torque, the higher the forces are
and the greater the resulting flexure of the neck piece that snaps.
You need to set the worm in its carrier and the carrier against the wormwheel
to reduce this torque to a minimum without indroducing too much backlash.

Andrew 

Subject:	My etx125 is broken
Sent:	Friday, September 24, 2010 11:25:13
From:	Tom Moore (tmoore@dfiequipment.com)
I've had my etx for 9 years and it won't power on.  Before the power-on
problem, the motors wouldn't work in go-to or with the paddle arrows.  I
opened it up, pulled a wire loose from somewhere.  I don't know where to
reconnect it.  I'm tired of messing with it myself.  Where can I send it
for diagnostic and then possible repair (if it's worth fixing)?
Mike here: Two choices: Meade (but they may decline) or Dr. Clay Sherrod. For Dr. Clay, see the Telescope "Supercharge" Service info on the ETX Site home page.

And:

Thanks for the quick reply.
I'll contact Dr Clay.
Your opinion -- How much money would you put into a 9 year old etx125 to
get it in top condition.  I see new ones for $900.
Mike here: That depends on how much you expect to use it and for how long. Since only the mount has a problem, you could put the OTA on a different mount. Or let Dr. Clay repair it and make it even better. On the other hand, perhaps it is time for you to move up a larger aperture telescope.

And:

I only 60 yr old and I plan to use it the rest of my life - say, until
I'm 100 and then give to my daughter.  Actually, I was using it a lot
before it broke - a lot (to me) means a couple of times a month.  I have
a 10" dob also but I like the portability of the etx.

What would I need to do to put it on a different mount?  What mount
would you suggest?
Mike here: There are some articles on mounting the ETX OTA on different tripods, such as a LXD, on the Helpful Information: Telescope Tech Tips page.
Subject:	Re: Broken ETX gear assembly....
Sent:	Friday, September 24, 2010 10:51:59
From:	P. Clay Sherrod (drclay@tcworks.net)
Hi Mark...good question.
The gearbox is intended to somewhat "float" as you suspect; the O-rings
give added suspension for this purpose as to not over-bind any of the
interlocking gear components during motion.  So get it firm, but assure
that the gearbox is still not completely down against the base floor as
it possibly could be.

Dr. Clay
_____
Arkansas Sky Observatories
MPC H45 - Petit Jean Mountain South
MPC H41 - Petit Jean Mountain
MPC H43 - Conway West
http://www.arksky.org/=20

  ----- Original Message -----
  From: Mark
  To: drclay@tcworks.net
  Sent: Friday, September 24, 2010 12:44 PM
  Subject: Broken ETX gear assembly....

   I have an etx 125 that has broken the RA gear assembly in the base.
   The ring that fits on the worm broke off, and I have made a repair.
   My etx has the newer style tapered clutch, and I have disassembled,
   and reassembled. My question is, how tightly should the gear box be
   screwed down? When I just snug the gears box against the o rings, I
   have a lot of movement that seems to stress that arm. I am afraid to
   screw it down all the way in case it should break a mounting tab.
   What advice can you give on tolerances and such for reassembly of the
   Ra gear box/worm gear assembly? Your help is great appreciated.

  Clear Skies!
  Mark 

Subject:	RE: ETX 125  electronic circuit plate
Sent:	Friday, September 24, 2010 04:43:13
From:	Avelino Dias (avelino_dias@hotmail.com)
Your help were once more very nice.
I saw also a video on the Youtube that helps me too.
 
So I ask you the exact mesures (millimiters or inches) of the tool/key
that is used to separate the control switch of the AZ motor. I dont know
if you understand me, so I want to put over the plastic piece in the
midle of the scope base that hold or not the AZ for manual moviments.
There is a litle screw that hold that piece to the metal axis of the
scope. I think is the same mesure of the srews used in the control of
the open lens to 90 or 45 degrees.
 
Att.
Avelino Dias
Mike here: Perhaps our resident hardware expert, Dr. Clay Sherrod, can assist with this information. Over to you Dr. Clay.
From:	P. Clay Sherrod (drclay@tcworks.net)
If you are referring to the LOCKING LEVER (chrome) for the RA/azimuth
axis, the small set screw is 0.05" standard.

Dr. Clay
_____
Arkansas Sky Observatories
MPC H45 - Petit Jean Mountain South
MPC H41 - Petit Jean Mountain
MPC H43 - Conway West
http://www.arksky.org/

Subject:	RE: ETX 125  electronic circuit plate
Sent:	Thursday, September 23, 2010 04:41:19
From:	Avelino Dias (avelino_dias@hotmail.com)
Once more I want to thank you for your exceptional consulting service.

Now I ask you if you have some manual or rules to dismont the ETX 125. I
need to dismont the botton part to separate the control panel from the
rest of the body.

If you have some tips for me I apreciate.
 
Att.
Avelino Dias
Mike here: There are several disassembly articles on the Helpful Information: Telescope Tech Tips page.
Subject:	ETX-105EC Declination problem
Sent:	Tuesday, September 21, 2010 07:46:17
From:	Auryn Hughes (auryn.hughes@greeve.co.uk)
I'm new to astronomy and picked up a Meade ETX-105EC second hand as the
offer was too good to refuse even if it was broken. I wanted to share
this experience just in case any others are having the same problems.

I managed to set the scope up and try it out manually first. Strangely
in the DEC plane the scope was clunky and not smooth at all. Thinking
this might be a clutch or DEC motor problem I turned the device on with
the electronic hand set and it worked ok apart from at about 45 degrees
there was a clunk and noticed the ETX holding arm was being pushed out.
I immediately knew this was not right.

So trawling the web for a know fix I came across your site and read up
about all the problems people were having with their motors, and found a
piece about drive jitters:

http://www.weasner.com/etx/techtips/etx105-dec.html

Following the instructions to remove the screws to get to the DEC motor
I went ahead to find the problem. On closer inspection however the motor
and worm gear were fine and the clutch appeared to be functioning
correctly. Back to square 1.

I then found a youtube video "ETX105-EC Disassembly" and took the bold
step to removing the OTA. After much faffing around trying to get the
focusing knob off (I think we have different sized Hex keys in the UK) I
managed to get to the other side of the mount. To my surprise there was
a chunk of cast metal wedged in the side arm. I presume this is meant to
be an end stop?

I tested the DEC motor again and the problem was solved. I think I now
need to be very careful with the DEC motor and hopefully this won't
affect the Autostar functionallity.

Hoe that helps a few people in case they have the same problem.

Regards
 
Awstriker
 
UK, Mid Wales

Subject:	RE: ETX 125  electronic circuit plate
Sent:	Tuesday, September 21, 2010 04:36:21
From:	Avelino Dias (avelino_dias@hotmail.com)
I just saw in your ETX FAQ that the positive is center pin.
So now I realize that I have smoke my circuit board.
I put it in a techical expert to try fixed it.
So I ask you, for yor experience, when this happends (it smoke just two
small conductive wires in the first circuit board), the motor stills OK?
 
Thank you again.
 
Att.
Avelino Dias
Mike here: How much damage was done will depend on many factors. But usually, the circuit board is all that is damaged.
Subject:	re: RA failure,no right movement
Sent:	Monday, September 20, 2010 15:54:03
From:	Nohr Tillman (ntillm01@yahoo.com)
I'd like to add some thoughts to Mr. Fowler's situation with his ETX-125
and the broken gear mount, and perhaps save one from getting tossed of a
cliff. I'd say, between all the great information on your site, and his
skills with model RC building, a fix for his scope is right at his
fingertips. Perhaps even a stronger fix than he had originally.

Yes, these great instruments do have issues because of assembly,
less-than-perfect parts or other things that cause issues. But it seems
that anyone who has taken the time to fix the issue has enjoyed a scope
that performs flawless from then on. I can attest to being proud of
every fix, adjustment and tweak to both of mine when I enjoy a great
evening imaging or simply observing through one. I offer the advice to
don't give up yet, Laurance!
 
My Two Cents,
Nohr Tillman
Troy, MI, USA, Earth

And:

From:	richard seymour (rseymour@wolfenet.com)
I'd suggest a direct email or phone call to Bill Vorce (Mr. Telescope
Warehouse).
He may have a motor unit kicking around that simply didn't get mentioned
on his website.
(i'd love to see his basement...)

good luck
--dick

Subject:	EXT 80 azimuth clutch Problems
Sent:	Sunday, September 19, 2010 14:33:57
From:	rharries@telus.net (rharries@telus.net)
Hello Lyle

If you get a useful answer to your question posted on Mike's web site
would you please let me know. I've tried both the answers Mike suggested
with no success.

The only way I can make things work is to wrap the threads with a bit of
duct tape.

good luck 

Ron Harries 
Salmon Arm,
Mike here: Lyle's original message was from a year ago. There is now the "ETX-80 Axis Repair" article, posted this month, on the Helpful information: Telescope Tech Tips page, which may help you both.
Subject:	ETX 125  electronic circuit plate
Sent:	Saturday, September 18, 2010 15:45:05
From:	Avelino Dias (avelino_dias@hotmail.com)
Unfortenely I just burned one of green circuit plate of my scope. I just
trying the AC adapter that I buy from e-bay.
I need to take some adaption on the electrical plug to fixes to scope.
So I saw some litle smoke going out there, and smell burned too. 
So I ask to a my friend that work with electronic reparation, and he
said that I need one new circut plate (green) that had burned, is the
first circuit plate of the scope, the one it fixed the bateries plug,
and I copy the its number:
66 94V0
h50961
15-6305-00 REVC
 
I ask you a favour to ask the Meade engenieer to look if the Meade
factory  can sell this circut plate to you and then you sell to me or
selling direct to me.
 
Att. 
Avelino Dias
Mike here: Typically, Meade does not sell such replacement parts. You would have to return the telescope to them for repair. Alternatively, you might be able to get a replacement board from Telescope Warehouse (link on the Astronomy Links page).

And:

Thank you for your reply.
I buyed an AC adapter that estabilize electric current that is used on
the Laptop (Assus, 12V - 3000MA). Afer I read one post of your site I
saw that must have a right position of the poles. I think my error were
about to connect plug with scope. Do you recomend that Ac ADAPTER? I
buyed that because I have a none estabilized electric current in  my
house.
Can you tell me what do you mean for a replacment board. Is the just the
electronic circuit near to the comand plug, or the entires electric
parts. I ask you if you recomend one specific seller.
 
Thank you again. I never saw a work like your, is very helpness to me.
Sorry my english.
Att.
Avelino Dias
Mike here: See the ETX FAQ page for the polarity of the external power source connector plug. If you got it backwards, that would damage the electronics in the telescope base. As I suggested, try Telescope Warehouse for a replacement circuit board for the one that has been damaged.
Subject:	RA failure,no right movement
Sent:	Thursday, September 16, 2010 19:33:41
From:	laurance fowler (foulowl.68@gmail.com)
Well after owning the ETX125 PE for three years,I guess I've dodged the
bullet too long.What a disappointment.After sitting up for the summer I
brought it out tonight to view Jupiter and the Moon.Setup went
normal.Go-To was ballpark.Minor corrections were necessary,but I
breathed a sight of relief when all went fairly well.(After visiting
this websight regularly,I've felt like I've had a sword hanging over me
since buying the thing).Well after viewing the Moon for 15-20 min I
started noticing a definite "tic" in the tracking.I loosend the locking
lever slightly hoping I had just overtightened,but knowing in my heart
that I hadn't.I've treated this thing like a newborn since purchase.The
problem continued,quickly worsened and now,no right movement.Just
clakety, clakety,clack.Just my luck.Left hand motion seems fine.Up-down
seems fine.Just No right hand movement.The motor is turning,but in my
minds eye I can hear some kind of stripped or broken gear.

Where do I start?I'm good with mechanics and tedious work as I am a RC
model builder,but realisticly...is it even worth my trouble and
headache?My brief love affair with go-to is done for.Should I just
consider moving the OT onto a decent clock style mount?Should I consider
making a nice lamp out of it?I'm fairly disgusted at the moment $1000
bucks was a big deal for me.Maybe Meade doesnt think so,but I sure do.
Mike here: There could be several culprits: loose gear, loose gear mount, broken gear tooth, wire catching someplace, or some other obstruction. You'll have to open up the base and have a look. Once you know what the problem is, it can be dealt with, one way or another.

And:

Thanks for the  reply.I'll be digging through your sight next day or so
to get the disassembly procedures.I know I've seen you directing people
there regularly in the past.Guess its my turn now.I just didn't have the
heart to tear into the old girl for an autopsy tonight.I'm still in the
grieving process...you know the ol'
story,denial,anger,depression,acceptance,cope.I'm sure you've been there
LOL.I'll let you know what I find in a few days.
Mike here: If I had to guess on the culprit, I'd say loose mount since it works in one direction but not the other.

And:

thanks for the tip Mike.I'll focus on the "loose mount" theory
first.That is unless pieces start falling out when I open it up.Im an
EMT here in South Alabama and about to go on shift for the next 72hrs
straight,so Im going to take the scope to work and try to tear it apart
in our communications room between calls.We're always working on
something or other in there.I really wanted to view Jupiter on or about
its opposition,so I hope its easily fixed.Its comforting to know I have
such a great resource in your websight and community.Thanks for all the
time and effort you put into this.

And an update:

Opened up the base of the afore mentioned 125pe.The problem was
obvious.The black plastic motor/gearbox chassis has failed.Broken off at
termination of the geartrain.The "arm" which extends off the main body
is snapped off on the axle.Part of it is still hanging off the main
drive gear dangling.Suggestion please?Ill include a pic just to show the
damage.The white nylon gears all seem umdamaged and the unit as a whole
still seem savable barring the chassis.

photo

Mike here: Ah ha, my quess was right! A broken mount. There are some gear repair articles on the Helpful Information: Telescope Tech Tips page that might give you some ideas. You might also be able to get a full replacement from Telescope Warehouse (link on the Astronomy Links page).

And:

Thanks for the link to Telescope WH.I checked their site for a new MM
but they dont currently have one listed.I'll check back occasionaly.The
fact is Mike I've been stewing over my options all weekend.After
disassemling the drive system,I must say I'm very disappointed in the
quality of the components inside as well as the assembly.Evey screw I
came to was not even finger tight.As I mentioned before,Im an RC Model
builder.I have built 4WD rc trucks with similar gearbox designs.I've run
them at 50mph over rough terrain into trees, water,you name it and
they're still going strong.Which forces me to ask myself," Just how
poorly made is this telescope drive that it cant even withstand being
pointed at the sky and ticking away a few nights a year"?Im just very
dubious now about investing much money into repairing a drive system
that after examination, is little more than a toy.Im leaning more to the
possibility of just moving the OT assembly (hope its built better than
the base) to a decent equatorial mount.After checking a few sites I
found that Orion seems to have what looks to be a decent mounts/tripods
in the $300-$400 range with optional clock drives.But I already have
this nice Meade tripod...Two of 'em.I dont need another.Is there
anywhere you know that I could look into a mount that would mate the
Meade OT assembly to a equatorial mount,then to my existing tripod?Or do
you have any better Ideas?For the time being,Im not giving up.I can
still use the up-down axis of the autostar controler,so Ive decided to
just polar align the scope tonight and well,I guess your talking to the
new RA drive for the time being.It worked for Galileo,guess it'll work
for me.Im just an observer not an imager anyway so I'll make the best of
it for now.If I can find replacement parts on the cheap,cheap I'll
consider repairs.But right now Im leaning more towards just replacing
the mount.I would really appreciate any suggestions you might have.

Thanks in advance, 
LA Fowler
Mike here: There are several tips about using alternative mounts on the Helpful Information: Telescope Tech Tips page. Have a look through them for ideas.
Subject:	re: Auto Focus problem ETX125PE
Sent:	Thursday, September 16, 2010 14:45:44
From:	richard seymour (rseymour@wolfenet.com)
A work-around for your problem seems simple:
unplug the focuser from the scope until -after- the "Getting Time"
period.
Then plug it back in.

The 1247 Focuser is a device which can be plugged in -after- the
startup, and will still be seen, recognized and used by the Autostar.

I have a 1244 on my ETX-90, and it is -not- triggered by the Getting
Time testing (whether or not my LNT is attached).  I believe they have
the same logic card as the 1247.

The "getting time" dialog is a packeted message to the AUX bus asking
"is there a clock or GPS out there?".   Your 1247 must be seeing itself
as "addressed", and taking floating wires (perhaps) as bad data,
interpreting it as "move".

I -suspect- there's a mild short circuit involved in your Autostar or
Handbox cable.  If you have the hand controller for the 1247, you'll see
that it is only a set of switches, short-circuiting the data lines (the
inner pair on the 1247's cable) in various combinations to tell the
focuser what to do.

As for Meade UK's suggestion about the "wrong" AUX socket... foo.
The AUX sockets are wired in simple parallel.  They are exactly the
same.

have fun
--dick

And more from Dick:

I *do* see the same problem....
(my apologies for saying i didn't... but i sure don't remember it)

With my patched copy of 43Eg (now showing as 43gg, due to the patching)
with both the LNT and 1244 plugged in,
I -do- get focuser run-away.
(unplugging the focuser and replugging stops the runaway)

I'll be testing the "grid" of issues:
with/without LNT, with/without patches.
But that'll take an hour or so.

At least I -can- duplicate it, and i'll certainly report it to Meade
(and/or patch it).

have fun
--dick

And:

Ooookaaay....

It happens both to my patched (43gg) and unpatched (43Eg) firmware.

This is an ETX-90 with the 1244 focuser on a normal 497 Autostar.

I'll try the 497EP to see if they "ported" this bug, too.

have fun
--dick
p.s. i'm CC'ing Andrew Johansen as a "partner in crime" for the patch kits.
Andrew: this bug was reported on Mike's most recent site update earlier today.
Mike here: Wow! Amazing this hasn't cropped up earlier! Like years ago!

And:

The bug does *not* appear with a 497EP Autostar running version 5CE1

have fun
--dick (one step at a time...)

And:

From:	Andrew Johansen (johansea@optusnet.com.au)
Gday Dick/Others

I dont have a 1244 or access to one, but have decoded the
firmware for the focusser, so will see if i can see why a
1244 would start running.
It uses a totally different Aux protocol, so should be easy to find
where it gets called., then its just a walk backwards.

Andrew

And:

What a great community this is, I was stunned to receive all these
emails this morning regarding this problem that has nagged me for ages,
actually got to the stage where I was not using the scope particularly
for imaging, which is why have the focuser because the scope is about
30/40mtrs away outside. Richard your first email made me think I had
missed something somewhere but reading the later ones was really great
news, thankyou.

A little background to summarise briefly what I found is the least I can
do and perhaps may help.

I had orginally thought it to be an electrical short in the scope to do
with the LNT/Focuser cabling where it traverses through the centre of
the Az clutch and up the fork arm. I pretty competent, but the
mechanicals around the Az clutch after I had looked at it was not an
area to mess with but I did check, test and protect the cables where
they come out of the tube. In the base, the end of the tube was very
rough and belled out with a split in it that had already caused some
chafing to the sleeve but not split the insulation. This was all done
awhile back, this last week having been to see my nephew who also enjoys
this great hobby I decided to have another go to nail the cause, I
tested both focusers with the same result and swopped cables on the
Autostar and tested them both (I have tools for making, repairing and
testing these) and the problem was still there. The next logical steps
were to investigate either the Autostar itself or the firmware.

In the meantime I had emailed Mike to see if he could help, he responded
so quickly, thanks Mike.

The firmware was easiest so I rolled it back to an older version 41ec
that I had. Initially the problem was there, but the focuser only ran
for about 3 seconds,  once the scope has been powered down and the
Autostar disconnected from the scope for a while the problem was gone.

I also tried 42ed from Mike's site, it seems to behave exactly the same
as 43eg, so I did not pursue it very far, note that I have only assumed
that it is the same glitch in both 42 and 43 firmware versions. (By the
way I tried with an without the patches on all versions. Patches edited
slightly to cover the enhancements I wanted, have not managed to test
all the enhancements yet but I really like what I am seeing, weather not
that good at the moment here in Scotland, will be able to fully explore
all these nice enhancements when the weather picks up)

I checked, by installing 41ec and 43eg three times before advising Mike
of what I had found in case anyone else was experiencing the same thing.
The one thing that really confused me was that no one else seemed to
have the problem. So it was really good to hear you confirm it Richard,
the sigh of relief was audible.

But what can I say, reading through all your emails I can only thank you
all for your time and effort and I will be absolutly delighted if you
can manage to provide a patch for 43eg, I somehow feel every confidence
you will.

Best wishes and many clear skies to you all,

Rick Revell

And:

> The firmware was easiest so I rolled it back to an older version 41ec that I had.
> Initially the problem was there, but the focuser only ran for about 3 seconds, once the
> scope has been powered down and the Autostar disconnected from the scope for a while the
> problem was gone.

Duration of disconnect should have no effect (HA!) upon the symptoms.
When the battery power is turned off, none of the devices (except the LNT's internal 
CR2032 battery) have power.  I expect your ETX125PE does not let you (easily) disconnect 
the LNT from the Autostar (it does not feed power back, so that should not matter).
My test rig has an external AUX plug for the LNT, so i can easily shuffle bits.

Andrew and i think that -maybe- it's the current DATE which is part of the problem.
One control byte which affects some of the AUX signal-routing system is x0A
The LNT uses only a two-digit Year BCD code, and this is "2010", or x0A, for the "10".
That would also explain why folks have not seen this (up til now).
I've been pretty much exclusively using my 497EP this year, so that missed it.
I'd guess that very few people have the combination of ETXnnnPE -and- an electric focuser.

The fact that 41Ec DID have the bug (at least once) speaks of a "noise" effect.
But why 43Eg would be more "noisy" than 41Ec is (as yet) difficult to say.

We're working on it (i'm going to do a few more mix-and-match before loading 41Ec).

Since we're suspecting "Data effects", i've been trying to set the date back to 2009.
And i'm seeing weird effects there, too... i get "2000" back from the LNT.
This mornings cycle of testing will include removing the focuser to see if that "fixes" 
the wrong-date effect.  (perhaps it takes two to entangle?)

have fun
--dick

And:

More on the date:
If the focuser and LNT are both plugged in, the date from the LNT gets messed up.
Sometimes.
IF it's SET to 2010, then "10" returns, and the Autostar sees "2010" on the next "Getting Time"
That's true for both with and without focuser (and "with" gets a runaway).

BUT: if the focuser is plugged in, and the date is set for any year less than 2010,
the next power-up sees "2000"  (not 2009, not 2008...)
BUT: if you then unplug the focuser, and power up, you get the year that you -set-.
So 2009 (or 2008) appears!
So the "SET" is working, it's the readback that's corrupted (and the focuser starts running).

So the data (and date) are definitely part of the issue...

... now to try 41Ec...

have fun
--dick
Mike here: Wow! Great detective work!
Hardly... it's typical "look for a pattern" testing.

Anyway: then i tried 2011
... and did NOT get a runaway .. the first time i powered up.
But the next time -did- runaway.
(part of pattern-testing requires more than one data point)
However the date that the Autostar saw in both cases was 2011.

Then i back-loaded to 41Ec.

The first power-up (After i reattached the focuser) saw a short (under 2 seconds) runaway.
All subsequent power ups (including after unplugging/replugging the focuser) saw full runaways.
So, for -me-, 41Ec does -not- cure the problem.
Setting older (2009) dates also brought back the "2000" date issue.

It is odd that 41Ec (occasionally) -stops- the runaway.

I did a few full-sequence sets (Date, Time, Daylight), just to make sure
i wasn't missing some "clean it up" step Meade may have included.

Thinking back upon this... it -is- possible that i hit the runaway when
actually using the scope.
But it was probably the "short" style, and out in the cold and dark with
other things going on at the time (i'll frequently have two or three
scopes (LS-6, LX200gps and ETX90) out at the same time to look for
similarities or differences in behaviour.)

Since this does seem to be "noise"-related, that means it may be difficult to patch "properly".
A work-around (get time, stop focuser) may have to be implemented.
At least the "run time" can be minimized (milliseconds).

All of my tests were at 20 C (68 F), colder temperatures may help.

more later
--dick

And:

Wow you folks don't hang about. I think you should know for me though I
had the problem back in 2009 and possibly late 2008 and I did not have
any date set issues that I can remember, maybe I missed it but I would
have thought that should have upset the goto. The LNT required a battery
change just before Christmas 2009 the scope had not been out for a
couple of months due to other commitments (Like Mike I am retired but my
services get called upon frequently, so never idle or bored) and the
fact that often I like to do some imaging and the focus problem was
making that sometimes difficult so enthusiam for hopping out into around
+3 deg C and less wained a bit.

Temperature has never seemed to be a factor as far as I can recall, I
had the scope out just before that Christmas 2009 which was quite cold
with snow and the problem was there indoors and outdoors. Also with 41ec
scope has been fine since this recent reload, now powered up about a
dozen times for various reasons although the weather has not been good
enough to get serious. My first and only short runaway with 41ec, around
2 to 3 secs may be less, seems to happen straight after reloading 41ec
from 43eg doing initial setups and then doing a hard restart ie power
off then on, usually but not always, to get a view to train the drives.

But after that, switching the scope off for a few hours and unplugging
the Autostar the scope and focuser work as they should do.

I was wondering if there was some remnant from 43eg quietly decaying
away in the background whilst the whole system was powered down for a
while, I have seen similar situations on complex communications gear in
the past.

Thanks a lot for keeping me updated it really is appreciated and of
course allows me to give a bit of feedback, as above, which I hope is of
some help.

Best wishes,

Rick Revell
Mike here: Dick and Andrew like a challenge! My current challenge is doing iPhone astrophotography. Some of the results have been pretty amazing.
Subject:	Re: Motor Fault
Sent:	Monday, September 13, 2010 20:36:30
From:	Shawn Machia (shawnmachia@gmail.com)
Thanks for the advice.  Changing the batteries fixed the problem, and
there was no corrosion.  However, I do have some other questions now
that I've taken it outside again:

1.  I lost the stupid tightening screw for the eyepiece, it fell in the
grass directly at my feet and I could not find it at all.  Can I just go
to a hardware store and get a small screw that will thread in there, or
will Meade sell me a replacement one?

2.  How can I check to see if my focus is working the way it should?  I
am concerned its not.  At higher magnifications I had difficulty getting
the object (Jupiter) in focus at all and sometimes when I succeeded, if
I slewed the telescope at all I would lose focus and then be unable to
get it back again.  The same thing happened with the moon.  This only
happened with higher magnifications.  Granted I could have had some
condensation blurring my image or something.  Keep in mind I haven't
done this for several years so I'm way out of practice.

3.  Is there any way I can clean my eyepieces?  I have not tried.

Thank you!
 
-Shawn
Mike here: For the eyepiece screw info, see the ETX FAQ page. As to focus, keep in mind there is a theoretical maximum magnification for any telescope. If you exceed that, the image will look fuzzy. For more on determining the maximum and how to calculate magnification, see the ETX FAQ page. Also, keep in mind that atmospheric conditions will influence how good the viewing is. And also, you need to let the telescope reach "thermal equilibrium" with the ambient air temperature for best viewing; rule of thumb is 20-30 minutes per inch of aperture. As to cleaning, see the article "Cleaning Optics" on the Helpful Information: Buyer/New User Tips page. But keep in mind that you don't want to clean the optical surfaces unless positively, absolutely necessary. If there is a lot of dust or debris or if there are finger prints, then cleaning is likely appropriate.
Subject:	ETX-80 part needed
Sent:	Monday, September 13, 2010 16:08:03
From:	Lyle Johnsen (lylej66@gmail.com)
I have been having trouble with the azimuth drive on my ETX-80. It is
not under warrenty. I took it apart a couple of times and now I think I
understand the problem.  Apparently some lubricant has gotten into the
azimuth clutch.  However, when I put things back together, the white
plastic nut (see attached photo) that holds the azimuth shaft together
will not tighten.  It has extremely fine threads that are now stripped. 
This may be a single-use part that must be replaced if it is removed. 
How can I buy a couple of these nuts?  I called Mead customer service
and was told that they do not sell internal parts.  Any suggestions?
Lyle Johnsen
Mike here: Try Telescope Warehouse (link on the Astronomy Links page). Alternatively, try your local hardware store.

photo


Subject:	Adding an LNT Module to EXT-125EC
Sent:	Monday, September 13, 2010 12:25:53
From:	Don Hadyk (DHadyk@comcast.net)
I just purchased a EXT-125EC on e-Bay and would like to add LNT
capability to it.  It was originally purchased in 2004 and appears to be
the older EC model.  I tried researching the various articles on your
site and got confused as to how best to accomplish this.  I would
appreciate your help and perhaps you can answer these questions or point
me to the correct articles?

1.        Which LNT module should I purchase?  Archived articles say
purchase one for DS2000 telescope.  Meade CS says purchase one made for
the EXT-125.  What is the best one to purchase.  If the DS2000, there
are two different LNT module versions which one to purchase?
2.       What is the best way to mount the LNT Module?
3.       Should I also plan on replacing my original finder scope with
the red dot?
4.       Should I update my auto star software to the latest version?
5.       What type of problems should I expect to encounter to get the
LNT module working properly?
 
Great site!  I look forward to seeing your reply 
 
Galileo
Mike here: I assume you are referring the articles "Adding a LNT Module" and "Adding a LNT to a non-LNT Telescope" on the Helpful Information: Telescope Tech Tips page. Since you'll be adding the LNT and its wires as add-ons, it probably doesn't matter too much which model you get. But I would recommend the ETX external LNT module just because it might fit a little better than a DS model. The later models have the lens on top, whereas the first models had it on the side. Top is better. As to mounting, see those articles. If you version of the AutoStar ROM is older than about 2005, I recommend updating to the latest version (4.3Eg); otherwise it might not recognize the LNT. As to problems, securing the LNT and getting the wiring right will likely be your only difficulties. The real question you should have is "why do I want to add the LNT?" What enhancements will it bring to you? You can easily master the techniques of leveling the telescope and putting it in the proper home position. That's really all the LNT does for you.
Subject:	Auto Focus problem ETX125PE
Sent:	Monday, September 13, 2010 10:46:13
From:	Rick Revell (rick.rev@btconnect.com)
Since updating to 43eg firmware have noticed that as the scope is
powered up the and the Autostar goes to 'getting time' after the welcome
screen it starts driving the Meade Autofocuser. Sometimes it is
continuous requiring a quick stab at the mode button or 0 button and
then the up or down buttons stop the Autofocuser from running, other
times it just runs briefly.

I have tried rolling back the firmware to 41ec but the problem with the
focuser exists still. I have also taken of the base and support arm
covers looking for damaged wiring. I was disappointed with the build
quality in particular the central down tube that takes the wiring loom
down from the fork arm was partially split and very rough edges and
cable chafing had already begun, I have now protected that area to
prevent further cable damage.

However the problem still persists with the Auto Focusser (I use it for
remote operation when Imaging back to the PC, don't have a laptop) I had
suspected it was a software fault but now having rolled back the
firmware this seems unlikely.

I have spoken to the UK Importers from whom I bought the ETX125 new.
They suggested I was using the wrong aux port and were unable to help
further the behaviour from both the aux ports is the same.

Any advice or tips on how to resolve this or what might be causing it
would be most welcome.

Your site is excellent a real wealth of information although nothing I
could find on my problem. Surely it is not unique
 
Many thanks,
 
Rick Revell
Aberdeen Scotland
Mike here: I'm not familiar with a "Meade Autofocuser" for the ETX. If you mean the Meade Electric Focuser #1247, I don't recall any similar problem reports. I assume you have tested the AutoStar without the focuser connected and all is well otherwise. Also, try running the focuser from its remote handbox and instead of the AutoStar; is it OK?

And:

Thanks for you very quick reply. Every thing seems to work normally
after this initial driving of the focuser at the getting the time prompt
and yes everything is ok without the focuser connected.

You are correct it is the Meade Electric Focuser #1247 (I should have
said), I actually have two of these the first had an eccentric drive,
would not work properly and was replaced, but they left me with the old
one. Other than the symptoms below both focusers will perform normally
both from the Autostar and the supplied handbox. The focuser at the time
of start up is run at what would be similar to medium speed set on the
Autostar (button 5 in autofocus mode on the Autostar, press mode for
more than two seconds and first item on menu, can also be accessed from
the 0/light button) sometimes continously sometimes for just a few
seconds it seems to be quite random as to which it does. This initially
made me suspect a software problem.

What is frustrating is having set the scope up with the imager installed
and having to power down for some reason or another and then on power up
the focus gets driven to the stops.

I guess I will have to investigate further, I am pretty technically
competent, to try and isolate where this voltage that is driving the
focuser is coming from the first move probably will be to disconnect the
LNT where the time is accessed. I would not at this stage put it past a
faulty Autostar

What would be really handy is the wiring/block diagram for the ETX like
you have for the Autostar #497 on you site, does such a thing exist? I
did not see it.

Obviously if I manage to nail this down I will let you know what I
found, you swift response and initial suggestions were very much
appreciated and it would be the least I could do.

Best regards

Rick Revell
Mike here: Three things come to mind that might help. Do a RESET on the AutoStar. That might clear out any corrupted memory issue on the AutoStar. If the problem persists, do a reload of 4.3Eg and then a RESET. Whether or not the RESET helps, be certain to CALIBRATE MOTOR and TRAIN DRIVES after the RESETs. Third, check the cable connections to the focuser; be certain the pins on the connector and jacks are clean, not too depressed, nor bent sideways. No schematics available for the ETX.

And:

Thank you again for all the info (do you ever sleep?) much appreciated.
Bit more information it now looks almost certain to be the firmware. The
version I rolled back to was Build 41ec was ok this morning after a
night with power off the scope and the autostar unplugged. Reinstalled
4.3 and the problem came back. Tried full resets and went through the
full set up routine. Pins on the connectors have all been cleaned and
look ok.

Now trying to find the latest Build that will work ok. Trying Build 42ed
patched just now will let you know what finally works when I am happy
with it in case someone else has this problem.

I suspect that for some reason the latest build is generating a voltage
that is used for something else but that I don't need and perhaps
intended for other scopes that have been added in the latest update.
What surprises me is that no one else has experienced this problem or
maybe most don't use this Meade focuser which is a bit crude to say the
least so the problem has not been passed to Meade. I can only report it
to the UK importers there is no facility for me to report it direct to
Meade if I try to they tell me to contact the importer.

Best wishes and thanks again,

Rick
Mike here: Are you reloading 4.3Eg from a local file or a fresh one from Meade's site? If local, your downloaded file could be bad. Just a thought. Yes, I sleep. Unless it is clear at night; then I'm usually in the observatory!

And an update:

Yeah me too regards clear nights, but here not so good, usually if clear
it's windy if not it's peein down as they say locally, I don't have an
observatory so wind tends to rock the scope if it's the wrong direction,
last few nights have been quite good with good seeing but the focus
problem has occupied me for some time now and was determined to get to
the bottom of it, have stripped the scope as you know looking for
electrical shorts and not happy with the finish of some parts,
particularly the down tube in the base through which the cable loom from
the arm passes very crude and rough, measures taken to protect cables.

So update - Yes the version of 43eg was fresh each time. Tried 42 (ed I
think got it from your site) also a no go.

Success - Rolled back again now to 41ec and Yes, as before, after
sitting through the night with Autostar disconnected from the scope
(#497) just powered up and no problems. I patched build 41ec with your
patch hopefully be able to track with the imager properly now.

I am pretty convinced now that it is something in the more recent
firmware builds to accomodate other telescopes that is causing this to
happen. I don't think I am missing too much with the ETX125 by rolling
back to that build I think most of the major gremlins had been solved by
then, never really found any problems with the scope other than this
focus thing with the more recent!! updates.

So away to train the drives again and if the wind drops will cal check
the sensors and then already to go.

Again thank you for all your help, keep up the good work with your very
excellent site, still finding out how really good it is.

Clear skies and lots of them and best regards,

Rick

Now

Subject:	William optics binoviewer
Sent:	Saturday, September 11, 2010 13:18:14
From:	Ross Elkins (rosse25@comcast.net)
I just took delivery of these yesterday. I tried them out on my nexstar
8 last nite but unable to go to my dark spot I reallly can't comment on
them yet. I managed to view m13 and andromeda , and Jupiter under these
poor conditions and I felt that I made good beginning with excellent
possibilities for this binoviewer. The false 3D effect looked good
especially on m13.

Today I will try to set them up terrestrially and iron out some
questionshat  I have as to setup especially focusing for each eye.

Do you know of a good article that gets into initial setup of my
binoviewer? All the articles I have read seem to be reviews that assume
or disregard whether u know what u r doing!

PS I see that I am going to need some sort of OTA balance weights for my
celestron and etx125. Any recommendations on a universal
assembly/supplier for both scopes.

Ross is on my iPad
Mike here: Other than the manual, I've not heard any of guides to use. I would suspect it should be straightforward. As to a "universal" counterweight system, you would need separate rails or mounting brackets for each telescope. Losmandy and ScopeStuff should have them. Or you could make something that work on both; see the Helpful Information: Astrophotography page for lots of tips on counterweights.

And:

Unfortunately there is no manual that came with it or on their site!

Ross is,
On my Iphone,
Mike here: I guess the operation is supposed to be intuitively obvious!

And:

Today I figured it all out setting it up in the daytime and trying
various lens barlow combos.
I was able to dispense with the 1.5 barlow that comes with it on my etx
which says a lot for it's compatiblity on a fast scope. It's much
brighter without the nosepiece.

Ross is,

Subject:	Broken RTA
Sent:	Saturday, September 11, 2010 00:41:02
From:	T.Yashi (yashi@sky.email.ne.jp)
By the way, my ETX has broken.
The screw that fixes the tube has broken.
If the broken screw can be taken out, I can repair by myself.

I append the reference photograph.

photo

Mike here: See the article "ETX-90EC DEC fix (Right Tube Adapter repair" on the Helpful Information: Telescope Tech Tips page.

And:

Thank you.
I will be able to repair my ETX.

Fortunately, the manager of car repair shop came to my home to carry my
daughter's car yesterday.
I told him to make a small hole for the center of the broken screw, and
pull out the broken screw by using reverse tap.
And I handed ETX to him.

I heard that he succeeded at his factory.
I will go to his factory to receive repaired ETX today.

If I buy the new screw, I will be able to use my ETX.

Subject:	ETX-125EC on its way  to Meade!
Sent:	Thursday, September 9, 2010 17:45:41
From:	James Grimes (rixner6@comcast.net)
Just a note to let you know I decided to let the technicians fix it the
right way. I was the one who was trying to find the circuit boards for
my scope, and couldn't, so I talked to one of the techs at Meade and he
advised me to send it to them, and let them repair it properly. I had it
taken apart, almost competely, and knew I couldn't repair it myself, so
I bubble wrapped everything and sent it in. I really like the optics of
this scope, and the views through it are great, so in a few months I
will have it back and out under clear skies along with my 6 inch
refractor. Thanks for all the input you gave me while I was trying to
solve the problems on my own. I will keep in touch, and you have a
really interesting web-site........Jim Grimes

Subject:	Re: etx 125pe help
Sent:	Wednesday, September 8, 2010 12:17:40
From:	on@matopoeia.plus.com (on@matopoeia.plus.com)
Dear Clay and Mike

Wow that was a quick response - Thanks you guys are stars. I have taken
your advice and inserted a washer between the circle and thrust
bearing/washer(which does protrude slightly from the axle) - the circle
had a small groove worn into it so maybe that could make the difference.
Everything went back together ok after a bit of fiddling to get the
scope back in the forks properly. The only thing i ended up doing inside
the right fork was to loosely tighten the gearbox screws which were very
loose indeed - hopefully that should calm the noise and maybe solve a
slight skip that was occuring last time out (cut short the best views of
jupiter I have ever seen).

It certainly does seem to feel tighter in the alt axis lock now - I need
to use 'finger and thumb' pressure to tighten it - much more and it
would require the whole hand if that makes sense (I hope that is not too
tight.) Obviously it is fully clouded over at the moment with forecasts
for rain = so I have updated the autostar and am running through the
rest of your performance enhancements in the meantime. Will let you know
how it fares when I get the chance to go out. Once again many thanks for
your help and guidance it is very much appreciated.

best wishes and clear skies
Oliver

And:

From:	P. Clay Sherrod (drclay@tcworks.net)
Great...I bet that does the trick.

Dr. Clay
_____
Arkansas Sky Observatories
MPC H45 - Petit Jean Mountain South
MPC H41 - Petit Jean Mountain
MPC H43 - Conway West
http://www.arksky.org/ 

Subject:	Virtual Star parties
Sent:	Wednesday, September 8, 2010 04:22:38
From:	Ian (ijwilliams@hotmail.co.uk)
Thanks for all the information on the ETX WebSite! I just got my hands
on my first goto scope, an ETX 70 and honestly, for such a small scope
it really exceeded my expectations!. Whilst doing some work with the
scope I had a thought about creating an open source virtual star party
website/program ( I am a systems engineer and software developer by
profession ). Do you know if anyone else out there is doing anything
similar? Google didn't turn up a great deal of information!.

The idea being a virtual astronomy club (or many) with a program that
can automatically slew the Telescope, Send co-ordinates to other scopes
with voice/live chat/imaging and forum facilities. For example, A remote
observer could be discussing a celestial object and then do a send to
the other remote clients software and prompting the remote user with a
'slew' request. Or subject matter experts doing remote tutorials and
presentations? Any thoughts or suggestions would be gratefully received.
Also if there is anyone else in the community who might be interested in
collaborating on the development project that would be fantastic!

Many thanks foe taking the time to read this email and again thanks for
all the ETX information, it has saved my scope a few fates worse than
death a few times now!
 
Ian Williams
United Kindom
Mike here: There are several Internet-controllable telescope systems online, but I'm not aware of any that provide all the features you contemplate having.
Subject:	etx 125pe help
Sent:	Monday, September 6, 2010 07:59:08
From:	on@matopoeia.plus.com (on@matopoeia.plus.com)
First I would like to thank you both for all the effort you have made to
share your experience and knowledge of the etx scopes with us - without
this wealthy resource I would probably have never taken the plunge, but
a few years ago now I did and now I am the proud owner of a etx125pe
(blue tube) and have enjoyed many hours spellbound behind it. Thankyou.
To my problem; of late I have been finding I need to clamp the locks
tighter and tighter to the point that now I am clamping as tight as I
feel comfortable doing but there is still some slippage occuring ( I am
sure you have heard this before...sorry). The dec lock is the worst
offender - it can barely support the weight of the tube. Having read
most of the contents of weasner.com I considered this would be somthing
I could remedy with the clutch degreasing operations. I have re-read
everything applicable and begun the disassembly without issue so far and
am now concerned about the most recent advice regarding removing the
optical tube support from the right fork arm to access the clutch, to
the point where I am considering if it is worth the effort and risk.
Just how many parts are going to escape if I were to tap the axle out
through the trunion hole? Is there any pictures of the assembly and the
parts? should I be attempting this at all? Please - any help you can
offer would be very much appreciated - I feel I should be capable of
this but I really value this telescope and would be heartbroken if it
were to go wrong - If I was on the same continent as you I would not
hesitate to have the supercharge service done but it would be
impractical to send a scope from the UK to you, and as the uk
distributor of meade products needed to send me 3 telescopes before I
got a fully functioning one when I bought it I would have little
confidence in them (sadly). Many thanks for your time Gents - wishing
you clear skies from the UK.
Oliver

And:

From:	P. Clay Sherrod (drclay@tcworks.net)
Sorry to hear about the problems with the telescope....I am surprised
that a PE edition is getting increasing slip.  Normally they reach a
point where they cannot slip any further. However, if you are having
this problem, avoid over-tightening.  You are going to strip out the
locking knob or worse the right fork arm trunion.

Also note that the normal "fix" for DEC slipping in the ETX does NOT
apply to the metal constructed PE editions.  There really is nothing in
the newer scopes to degrease and there is a single spacer ring directly
beneath the locking knob and fake setting circle that may be worn
out....take off the knob and look at that tiny collar (it will be around
the small axle going into the DEC drive). That collar MUST protrude out
enough to clear all the rest of the trunion.  If it still does, then buy
a large Fender washer at a hardware store, about 1.5" with a 1/4" hole,
and put that between the collar and the fake aluminum setting circle.

That may take care of your problem.

Best of luck.

Dr. Clay
_____
Arkansas Sky Observatories
MPC H45 - Petit Jean Mountain South
MPC H41 - Petit Jean Mountain
MPC H43 - Conway West
http://www.arksky.org/

Subject:	Motor Fault
Sent:	Sunday, September 5, 2010 20:16:26
From:	Shawn Machia (shawnmachia@gmail.com)
My name's Shawn.  I have an ETX-70AT that has been in its case for at
least two continuous years.  I took it out recently and went to
calibrate it.  Upon turning on the autostar, the telescope immediately
slewed horizontal and upside down (the eyepiece was pointing downward)
without any command given.  Once it reached its maximum rotation the
motor continued to run itself.  I turned off the unit and when I turned
it back on I had no motor response and got the motor fault message when
I used the calibrate function in the setup menu.  My first instinct is
that the batteries (six duracell AA's) are discharged from simply
sitting two years and can no longer carry the motor load.  I haven't
gotten fresh ones yet.  My concern remains however because the motor DID
run initially, and the autostar continued to work.  The batteries work
individually in my other appliances too, so they carry some charge.  I'm
nervous that because the motor sat so long unused, something went wrong
with it.  What do you think?

Thank you,
-Shawn
Mike here: First, if the batteries were left inside the base for two years, I suggest you check for corrosion in the battery compartment. If you find any, clean it up immediately. MOTOR FAULTS can occur from low battery power. So, replace the batteries with good ones. Then do a CALIBRATE MOTOR. If that doesn't solve the problem, do a RESET, CALIBRATE MOTOR, and then TRAIN DRIVES.
Subject:	Problem on my meade ETX 90
Sent:	Friday, September 3, 2010 15:37:38
From:	Dietmar (dietmar_stolzenberg@web.de)
i have a meade etx 90. My problem is, that the circuit board is scorched, 
my father can build a new one, do you have a wiring diagram. or can
you say me were i can found it.  Could no find a plan on the net.
 
With friendly greetings
 
Dietmar

photo photo

Mike here: Sorry, no schematic available on my ETX Site. However, you may be able to get a replacement board from Telescope Warehouse (link on the Astronomy Links page).
Subject:	re: ETX-125 immediately slews and won't stop
Sent:	Thursday, September 2, 2010 20:47:16
From:	richard seymour (rseymour@wolfenet.com)
That's also (occasionally) a symptom of a broken wire in the handbox cable.

You could try the old trick of swapping the cable end-for-end.
That shuffles which wire does what, and may change the symptoms.

If it does, then it merely becomes a "change the cable" repair.

good luck
--dick

And:

On 9/2/2010 8:54 PM, Loren Jackson wrote:
> Thanks, Dick.  I actually tried that already.  No luck.
 >  It slews even if the handbox isn't plugged in.

That's a BIG CLUE that it's a bad cable/connector.
If you can borrow another Autostar, you could determine if it's an
Autostar problem or an in-the-scope problem.

If it's in the scope, then the next step is to open up the scope bottom
and look for a loose connector (or cut wire) inside the scope.
Opening the bottom is easy... the three screws are probably hidden under
the rubber feet.
Remove batteries before opening, since the bottom plate is on short
wires, and their weight can cause problems.

good luck
--dick

> Appreciate your suggestion though.  Can't believe how many people have
tried to help.  Lots of nice folks out there!

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