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Last updated: 30 April 2010
This page is for comments and user feedback about the "ETX Classic" telescopes. ETX Classic models 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:	Need a little help!
Sent:	Saturday, April 24, 2010 13:24:46
From:	Paul W Shanabarger (
Dear Sir:

When I connect my Autostar Remote (ETX 70) to HDBX, I get this
message.`` Motor Unit Fault``

The problem that I am having, deals with the HDBx port. I can`t make any
connections.  I thought about getting a new remote, might solve the
problem. Something tells me it`s the HDBX port, that`s giving me the
trouble. Do you know anyway of getting this fixed?

Thank You
Mike here: First, my sincere apologies for not responding sooner. As you have no doubt read on the various Feedback pages on my ETX Site, I typically answer emails very quickly, many times within minutes of their being sent to me. So, it was with considerable unhappiness that I discovered your email from three days ago, deleted UNREAD as SPAM due to the ambiguous and SPAM-like Subject line entry. As discussed on the "Electronic Mail Etiquette and Submittal Guidelines" that I request all Site visitors to read BEFORE sending email to me, emails with out a descriptive Subject or emails with a SPAM-like Subject are likely to be rejected as SPAM and not read. Your email fell into the SPAM bucket. Fortunately, I accidently stumbled upon it. Please accept my apologies for this tardiness. BUT please do read the "Electronic Mail Etiquette and Submittal Guidelines" to avoid this happening in the future. Thanks for understanding. As to your problem, I assume you are using the AutoStar #494 that comes with the ETX-70. Have you changed the batteries with fresh ones? Are they inserted correctly? If the batteries are OK, try unplugging and replugging the HBX cable. That can sometimes cure connection problems. If that doesn't help, check the HBX jack and connector; the pins should be clean and not too depressed nor bent sideways.
Subject:	How deep sky objects look in your telescope
Sent:	Tuesday, April 27, 2010 03:18:41
From:	Johnny Landgren (
Just want to tip about a site that might be as useful to many of Your
readers as it have been for me. Its named "The Deep Sky Archive" and
found on:

In the archive one can search drawings of more than 5000 observations of
deep sky objects submitted by amateur astronomers with varios
telescopes. The images give a very good example of what to expect when
visually observing different objects thru your telescope.

All material is public without registration but if you register you can
also upload your own observations right to the database and they will be
available for everybody to view immediately.  I myself just registered
and added some of my first drawingsto the site, all done under
observations with my ETX 90.

Johnny Landgren
Hjorted, Sweden 

Subject:	ETX70 Focusing Problem - Apr. 26 update
Sent:	Tuesday, April 27, 2010 00:51:05
From:	Ron Harries (
I had the exact same problem with my barlow focusing on my ETX80. So,
out of frustration, and with no reasonable hope of success, I cranked
the focus completely in the other direction. Before I came to the end,
the telescope came into perfect focus. Strange.

Ron Harries
Salmon Arm

Subject:	RE: OPT Camera Adapter
Sent:	Monday, April 26, 2010 21:48:04
From:	Thomas Lebryk (
Thanks so much for the help!!!  If I ever get this to work, I will post
it on CloudyNights.  It gives me hope that if I remove all the rubber
grip material, it might just work.  We'll see, the eyepiece is on order.


Subject:	OPT Camera Adapter
Sent:	Monday, April 26, 2010 16:09:04
From:	Thomas Lebryk (
I saw your small review of the OPT Camera Adapter and pictures and I
would like to try it.  But I am trying to find out some exact
information about it.  If you can, please measure the inside diameter in
mm's of the main tube that the eyepiece goes into.  I am trying to find
out which of my eyepieces will fit without having to buy the adapter
first.  I know this sounds silly, since it is only $20, but I don't want
to waste the money!

The Owl Astronomy guy named Tom measured the inside of their's and he
said "just about 38mm".  It seems the OPT might be the same
manufacturer?  The design looks identical.

Also, I recently purchased a Nikon Fieldscope eyepiece at a huge
discount and have been looking for a way to create my own housing for
this non-standard eyepiece which is approximately 39mm at the largest

Would you have time to do this???  Thanks for any help.

Mike here: Yes, not all eyepieces will fit inside "eyepiece projection" adapters. Especially those with larger barrels or rubber grips. The OPT adapter accepts 1.25" eyepieces but I will have to go out to the observatory to measure the I.D. Just measured it. The adapter measures 30mm to accept the 1.25" eyepiece tube. However, the adapter will only accept eyepieces with barrels up to 38mm in diameter (and that would be a tight fit).
Subject:	ETX forum
Sent:	Friday, April 23, 2010 19:44:55
From:	Andy & Leah Lancour (
Hi Mike, what do you think of having a forum for ETX owners on your
site? You could be the moderator, and many of the members could probably
answer a lot of the questions that come up, taking some heat off of you.
Mike here: This is addressed on the Site Guide (on the ETX Site home page). There is the ETXAstro Yahoo Group for those who want to submit questions there.
Subject:	ETX-70 Focus Issue
Sent:	Friday, April 23, 2010 03:15:41
From:	Rick Shelton (
I have a ETX-70, one of the older models, the autostar plugs into the
base like the ETX-90. Anyway, I can achieve focus using the supplied 20
mm and 9mm eyepiece fine, but when i use the 2x barlow the focuser
bottoms out while turning clockwise and never reaches focus. It also
doesnt reach focus using a back cell adapter and tring for my camera as
well. Is there something I can do to correct this? The Barlow is the
"Series 4000 #126 2x Short-Focus" barlow......



Mike here: I've used the #126 Barlow Lens successfully with the 25mm and 9mm eyepieces that came with my ETX-70AT. As far as I know, the OTA is the same on both models. I wonder if the objective lens housing is sticking at one end of the focusing range. Or perhaps, something is wrong with the Barlow Lens.


Hi Mike thanks for the reply, I have since checked the barlow in a 130
reflector and it works fine using either eyepiece. I wonder, can the
tube that holds the Obj lens be adjusted? It only needs to come in
toward the arms a 1/2 or less im guessing to achieve focus.

Thanks again.
Mike here: Well, the focus shaft connection can not be easily changed. It would take some major surgery and you'd run the risk of making things worse. One thought: is the Barlow Lens full seated in the eyepiece hole? Or perhaps NOT fully seating it would help focus.


I also have a DSLR and using a T-ring adapter and rear cell adapter it
also doesnt focus, and using a 1 1/4 eyepiece adapter in the regular
eyepiece it doesnt either... the obj lens looks as if it has never been
damaged in any way, it just while turning clockwise (shortening the
tube) it quirts turning just before focus... Everything is seated fine.
is there a stop on the focus shaft or does the obj lens bottom out
against something?

Mike here: The objective lens housing moves from one end of the focus range to the other. I suppose there could be a burr or some obstruction preventing it from moving the full range. The articles "ETX-70AT Repair Guide" and "ETX-70 Focus Knob Fix" on the Helpful Information: Telescope Tech Tips page might help.


Thanks again for the tips, will dig around some more on your site, which
is excellent btw,,,

Take care


Mike, just had a brainstorm, lol not much of a storm maybe a lt drizzle.
Anyway you have the same scope as me I think, the 70 with the autostar
that plugs into the base correct? If so I turned the focuser all the way
clockwise to where it stops and the shortest that my scope would be. It
measures 10 and 5/8 inches (see attached pic) can you measure your scope
and see if its the same?



Mike here: My ETX-70AT has the HBX connection on a fork arm. But I suspect the OTA is the same. Mine measures 10-1/8".


Well that sounds like the culprit, cause it is almost at focus and the
extra 1/2" would be enough to reach focus. Thanks for the help, now I
know where the problem is.

Sorry about the mixup on the scope, yeah mine is just like the etx-90
base with the power supply connection and extra aux port. It also came
with the #497 controller and instead of the MA25mm eyepiece it came with
a SP20mm. I think meade went the cheap route with the newer 70at's after
this one.

Thanks again for your time, it is very much appreciated.


And an update:

Hey Mike, just wanted to update you on the scope, after getting the rear
housing off (which was a pain) and removing everything I noticed a
c-clip on the threaded rod that keeps the rod from going to far. Well it
was about a 1/2 inch from the end of the threads so I removed it and put
everything back together and now I can focus with any eyepiece and
barlow combination. That c-clip isnt necessary cause the rod will only
turn so far anyway. Thanks again for your help...


Subject:	[none]
Sent:	Sunday, April 18, 2010 13:30:34
From:	Randy Bost (
I have read several of your posts about power supplies for the Meade
scopes and must say there is quite a bit of info there.  The only thing
I haven't been able to ascertain is the polarity of the plug that
connects to the Computer Control.  Can you tell me if the center or tip
is positive or negative.  Any assistance with this will be greatly

Thank you,

Randy Bost
Mike here: First, my sincere apologies for not responding sooner. As you have no doubt read on the various Feedback pages on my ETX Site, I typically answer emails very quickly, many times within minutes of their being sent to me. So, it was with considerable unhappiness that I discovered your email from two days ago, deleted UNREAD as SPAM due to the missing Subject line entry. As discussed on the "Electronic Mail Etiquette and Submittal Guidelines" that I request all Site visitors to read BEFORE sending email to me, emails without a Subject or emails with a SPAM-like Subject are likely to be rejected as SPAM and not read. Your email fell into the SPAM bucket since it had no Subject. Fortunately, I accidently stumbled upon it and so I can now answer your email, tardy though my response it. Please accept my apologies for this tardiness. As to your question, it is answered on the "ETX FAQ" page on the ETX Site home page.
Subject:	Re: Auto Focus on ETX125EC  not working
Sent:	Monday, April 19, 2010 13:49:44
From:	Freda Kraus (
Bingo,     I called Meade and the tech walked me through  everything 
and that is exactly   what the problem  was,  the cog wheel was not
tight.  Now  that it is tight and seated fully onto the shaft   it is
working fine.    Thank you.
Mike here: Thought that had to be the culprit!
Subject:	Re: Second hand ETX125EC
Sent:	Monday, April 19, 2010 07:36:43
From:	Juan Manuel Soares de Lima (
With my ETX125 I have only a standard 26mm eyepiece and I've decided to
buy a 2x Barlow lens.

What eyepiece (not too much expensive) will yo recommend me to buy in
fist place? And as a second option?

Thanks again (and again)

Juan Manuel
Mike here: There are several articles on eyepieces on the Helpful Information: Buyer/New User Tips page. Also, see the Accessory Reviews: Eyepieces page. Keep in mind, the choice of additional eyepieces will depend somewhat on the types of observing you plan to do.
Subject:	Auto Focus on ETX125EC  not working
Sent:	Sunday, April 18, 2010 09:38:41
From:	Freda Kraus (
We purchased a used  ETX125EC  that came with a Meade 1247 Auto-focuser
already attached.   After spending some time setting  it up and trying
to  obtain focus  we have determined that the auto focus  may not be
working.   We anted to remove it and reinstall the manual knob  to  see
if  focus can be obtained. The problem  is the original   installer did
not save the screw  that was removed  to install the AF unit.    So  at
this point we are stuck,  I can't pull the AF  as I cannot reinstall the
manual   system  because of the missing screw.  I do have the knob  at
least.    Any suggestions  as to where and what kind of screw I need to
locate to  get the scope serviceable?   Or do you think  that there
might be something else wrong here?

Thank you
Mike here: First, the #1247 is not an "auto" focuser, it is just a motorized focus mechanism. As the setscrew for the manual focus knob, I don't have size but you can use almost any small knob as a replacement. Check your local hardware or Radio Shack store. Word of caution: when you remove the #1247 focuser, be certain to keep the telescope tube pointed upwards. Otherwise, you run the risk of the focus shaft slipping inside the telescope tube and you really don't want that to happen. As to what might be wrong with the focuser unit, which controller are you using to run the focus motor?


Thanks for the prompt reply.   
I  did read  someplace that it was very important to keep  the scope 
pointed up   to  avoid  the mechanism  from  dropping into the tube,  so
we  are ok there.   I managed to get the unit off,  it seems to  be
working fine  the gears are all metal. I did look  into the  unit once
it was off to be sure that the  motor was  infact turning the  gears, 
which it is.     With  the unit off  I tried manual focus  still nothing
comes into focus.   When I look down the open  eyepiece  hole  the
image is  in view  it just is not  reflecting up into the eyepiece.

As for which  hand held we were using,  I actually tried all 3,  the 
one that obviously  goes to the  focus  motor,  the  regular  handheld 
( with the 4 lights)  and the autostar   hand held.  With each one  I
can hear the motor running  which tells me that there is communication. 
It is entirely possible  that I might be doing something wrong  or
overlooking something obvious,  that is always a possibility.
Mike here: It sounds like electric focuser is working properly. If the light is not coming up into the eyepiece hole, is the flip mirror at the rear telescope set properly? It flips to reflect light to the top-mounted eyepiece or out through the rear port.


The flip mirror  is the first thing I checked.  When I said  that  it
was not reflecting  into the eye piece   I guess what  I was trying to 
describe was    that I saw an image  in the tube hole  but  the  image  
could not be focused in  the  eyepiece  (  plossl  26mm  nor the 40mm). 
I also tried  the rear  camera port   flipping the mirror  to  sent the
image to  the rear port,  still no  focus can be achieved.

When we  tried it outside   we could see colors   ( grass green)  is it
perhaps  that we tried focusing on something only 100  feet away?     
Is there something else that we could try   to bring it into focus  or
could the scope be damaged?
Mike here: Try focusing on a distance building or tree. Or if you can see the moon tonight, try it.


Cloudy here tonight  so moon is out.  Tried  trees and a house about
2/10  of a mile.     still no change in   view    still just 
featureless   colors
Mike here: If you are still using the electric focuser and have run it fully in both directions, it sounds like the gear is slipping on the focus shaft. Its setscrew could be loose.


Where is the set screw located?     We did try to manually focus    but
no luck there,  but that was just with the gear wheel   that is 
attached to the scope.  I know we must sound like idiot's  but   I am
beginning to think  it can't be fixed.
Mike here: There is (or should be) a small setscrew on the side of the shaft on the gear that is on the focus rod shaft.
Subject:	Problems with Auto level on ETX-125PE
Sent:	Sunday, April 18, 2010 04:13:01
From:	Kevin S. Ladin (
Recently, my beloved ETX-125PE has been malfunctioning.  I've noticed
that during automatic alignment it doesn't seem to level properly
anymore.  It gets to just shy of the horizon, both initially and when
finding tilt.  Thereafter, even though it reads "alignment successful"
on my Autostar after centering the two bright stars, it is way off when
slewing to objects.  I've gone through the procedure to train the drives
to no avail.  Any suggestions would be very much appreciated.


Kevin Ladin
Mike here: Keep in mind that the OTA may not end up level nor pointing to North at the end of the leveling and north-ing. That said, have you done a CALIBRATE SENSORS? Have you checked the Daylight Saving setting?


As always, thanks so much, Mike.  You are the best!!!!

Subject:	Electric focuser for ETX 80
Sent:	Saturday, April 17, 2010 08:32:02
From:	Ron Harries (
(Mike, if you object to cross posting please excuse this email. I'm
trying to get as much coverage as possible so I posted on the Meade
Uncensored Group.)

Has anybody tried to motorize the focusing of the ATX 80? I want to try
so was wondering if it had been done and there was some information to
give me a head start. The 1244 looks like it could be adapted but
according to Meade, this is not the case and they had no suggestions for
me. As I expected.


Ron Harries
Mike here: There are several such articles on the Helpful Information: Telescope Tech Tips page.


I've spent most of yesterday trying to find something on your site and
other sites. Your are corredt in saying that there are lots of articles
relating to ETX scopes but i"ve not been able to fing anything relating
to the 80.
Sometimes I wonder how rare the ETX 80 is.
Mike here: Yeah, not much on focusers for the ETX-80, just these specific articles: "DIY ETX-80 Electric Focuser" and "Electric Focus for ETX-70/80". And of course, several other articles on electrical focusers that you could likely easily adapt for the ETX-80.
Subject:	Re: Second hand ETX125EC
Sent:	Friday, April 16, 2010 04:52:39
From:	Juan Manuel Soares de Lima (
Thank you very much, Mike. I fixed the problem. Now I have to clean a
little the optics and face that collimation process. Several articles
talk about it but I can't find a tutorial or howto from the beginning by
now. I'll keep searching...
Thanks again,

Juan Manuel
Mike here: See the article "Cleaning Optics" on the Helpful Information: Buyer/New User Tips page. No tutorials but several articles on collimation in the "Star Testing and Collimation" section on the Helpful Information: Telescope Tech Tips page.
Subject:	ETX70 Focus Knob
Sent:	Thursday, April 15, 2010 05:24:16
From:	Staci Carroll (
Can you or your community please help...I recently acquired a ETX70
telescope and I am so excited as I am a beginner to the telescope world.
My telescope is missing the focus knob and I am desperately seeking one.
Does anyone have one to sell or any other suggestions?
Thank you!!!
Staci :) 
Mike here: You can likely find a replacement that will work at Radio Shack or your local hardware store.
Subject:	Second hand ETX125EC
Sent:	Wednesday, April 14, 2010 13:47:52
From:	Juan Manuel Soares de Lima (
As I tell on a previous mail, I recently bought a second hand Meade
ETX125EC. I can't see anything trough the telescope, I don't know if are
missing pieces or something else...
I open the telescope but I could not understand how it works.
Can you tell me where can I get some diagrams or pictures from inside
the telescope?, (number of mirrors, distances between, etc)
Thanks a lot
Mike here: There are various articles on disassembling the ETX on the Helpful Information: Telescope Tech Tips page. But lets see what might be wrong before you take things apart. When you say you can't see anything, what have you done? I assume you have removed the aperture cover. But what about the flip mirror at the rear of the telescope. What eyepiece are you using? What object have you tried to look at?


The tube don't have cover lenses, flip mirror is well positioning, adn I
can't see any light.
When I get the telescope I noted something loose inside the tube. I
found the focus knob in the box where the tube comes, so I assume the
other parts of the focus mechanism where loose inside.
I open the telescope, and as I suppose, I found a piece of metal and a
But, what I could not understand was that the circular piece of metal
where the focus mechanism should be connected, was screwed on the mirror
at a distance higher than the focus mechanism long.
I send a draw but with my poor english I'm not sure you can understand.
First draw is what i saw and the second is what I suppose to be the
mirror so the focus mechanism could reach the circular metal piece where
it should be connected.
Hope you can understand, thanks


Mike here: Egads. Has the primary mirror come loose and shifted that far along the tube? It is obvious that the focus shaft has come loose (since the knob was off). See the articles "Focus Shaft Fix" and "Doc G's ETX OTA Guidescope & Disassembly Photos" on the Telescope Tech Tips page. Once you have everything back together, you may have to recollimate the optics. Do a "star test". There are articles on star testing and collimation on the Telescope Tech Tips page.
Subject:	ETX 125 EC newer version dec. knob/trunion stripped
Sent:	Wednesday, April 14, 2010 05:32:32
From:	Bill McLean (
I got the knob off. The plastic tab that keeps the trunion from turning
in the side arm is broken- the trunion turns. I removed the trunion and
am either going to drill it out and run a bolt through it and epoxy it
in the side arm or just leave the trunion out and glue in a slightly
larger bolt. I'm thinking of a wing nut instead of jury rigging the knob
to hold a nut on the outside.

Before I do this I want to get your input. Also are after market
(possibly metal) parts available?

Carpe Noctem
Bill McLean 
Mike here: There used to be a replacement Right Tube Adapter but it is no longer available. You could contact Telescope Warehouse (link on the Astronomy Links page); perhaps they have one. Alternatively, see the article "ETX-90EC DEC fix (Right Tube Adapter repair)" on the Helpful Information: Telescope Tech Tips page.
Subject:	Meade focuser query
Sent:	Wednesday, April 14, 2010 03:11:00
From:	B Stewart (
My name is Brendan and I am from Norwich, England.
Can you help me with a query please? Have looked on the site but cannot
locate!! :o(
I have a Meade ETX-60 (the rucksack kind!) and saw an extended focuser
to replace the knob for sale so, bought it. Seemed like a good idea
except there is no grub nut to undo to replace it on my Meade! The knob
in question is parallel to the EP and not facing out backwards. Is it
possible to undo the knob or is it one unit? Don't want to fiddle too
much as a telescope without focus kinda becomes redundant!
Hope you can help.
Mike here: I don't have an ETX-60 so don't know how it attaches. Other models have a small setscrew on the side of the focus knob that holds the knob on the focus shaft.


Thank you.
Could you send the link to me too if poss?


Mike here: It will be on the "ETX, General" feedback page.
Subject:	Re:ETX alignment vs. ETX manual (12 Apr 2010)
Sent:	Tuesday, April 13, 2010 09:33:05
From: (
For Auto Align, the position of the tripod legs is pretty much
irrelevant. As I said in the article, the goal is to have the OTA
pointed to the west or slightly southwest when it is in the Home
position (fully CCW). The reason is that if the OTA is pointed too close
to magnetic north when the Autostar begins to slew the scope searching
for magnetic north, the sensor can miss the first null, which is north,
and hit a false null at magnetic south. This is especially true when the
magnetic declination (deviation) at your location is very large.

If you find it convenient to use the tripod legs as an indicator of
approximate north, that's fine but it really doesn't matter. Using the
OTA as an indicator of correct position applies both with and without a

Mike Hogan


From:	Ludwig Krijgshaftig (
Thanks to both of you for the comprehensive answer.
All clear now and it has been a pleasure to use the ETX on my dark site
in Brazil.

(Auto) Alignment was successful every time. Sometimes I had to repeat it
though as the Dec axis slipped when I changed eyepieces (and therefore
the balance of the OTA). I am always afraid to tighten it too much and
wind up not tightening enough I suppose.

Limits of the ETX-125PE have also become clear here. Although many many
wonderful objects can be observed, a large number of Messier galaxies in
the Virgo galaxy cluster are really not resolved with enough detail to
enjoy. Aperture fever lurks... Will try and see those with my 8" LX200R
back at home in The Netherlands, but light pollution overthere usually
takes away a lot of detail.

Kind regards,

Subject:	Updates
Sent:	Monday, April 12, 2010 13:25:35
From:	Brian Roberts (
Could you please send your excellent updates to my new address
'' ?

Many thanks. Regards Brian Roberts.
Mike here: Sorry you missed all the announcements back in October and November of last year. Email updates ended. For more information, see:
Subject:	Re: ETX 125C
Sent:	Monday, April 12, 2010 10:00:31
From:	P. Clay Sherrod (
You might attempt so high potency bonding glue at the crack.  The Alt
hard stop DOES break easily if the scope is moved past the stop point,
and it can be repaired using a simple 6-32 bolt and nut in the place of
the plastic hard stop, nut installed on the outside of the fork arm
plate where the "setting circle" resides.  It works excellently, but you
must position the bolt precisely right so that you can get the scope in
a 90 degree orientation for alignment.
Dr. Clay
Arkansas Sky Observatories
MPC H45 - Petit Jean Mountain South
MPC H41 - Petit Jean Mountain
MPC H43 - Conway West 
From:	s lanewala (
Hi Dr. Clay:

Another excellent suggestion!  And if I fall flat on two-left-thumbs,
then I can always get the other fork mount!




Good plan!
Dr. Clay

Subject:	Re: ETX 125C
Sent:	Sunday, April 11, 2010 14:59:50
From:	P. Clay Sherrod (
Why do you want to remove the fork arms?  They cannot be take off the
turntable base, since they are permanently bonded to the plastic.

You can remove the knob, but to do so will ruin the knob and likely the
trunion on the OTA mounting plate.  Wedge a large flat blade screwdriver
behind the knob flat surface against the fake setting circle and
leverage OUT while you turn the knob CCW.  Keep working it and it will
finally come out.  The knob is completely stripped as is likely the
trunion receiver threads.
Dr. Clay
Arkansas Sky Observatories
MPC H45 - Petit Jean Mountain South
MPC H41 - Petit Jean Mountain
MPC H43 - Conway West 

----- Original Message -----
	From: s lanewala (
	Hi Dr. Clay:
	My ETX 125 right fork clamp was overtightened some time ago and I cannot
	get it loosened up so I can remove the fork arms...
	Is there a quick way to get it loosened up?
Mike here: Saify, are you trying to remove the ETX OTA from the fork arms, or just the Altitude locking knob?


I wanted to remove the Alt locking knob, but since I couldn'tdo it
directly, I thought perhaps I could do it a bit differently.  As it
turns out, I was able to get the Alt Lock to loosen up, an d come off. 
But I did notice a few bits of plastic,and it seems like the Alt stop
has been sheared off.  Also, there seems to be a crack in the base of
the right form arm.

I guess that means that the fork arm assembly must be replaced

Any guidance?


Mike here: You could consider replacing the mount with either another ETX-125 mount or a different mount, like a LXD55/75. If you want to try for a replacement, contact Telescope Warehouse (link on the Astronomy Links page). If you want to see how you could attach the OTA to a different mount, there are some articles on that on the Helpful Information: Telescope Tech Tips page.


Thanks!  That means I replace everything except for the OTA, yes?  I
guess the fork arm  is integral to the base..   I will read about this
on the site.  Thanks.


Mike here: Yep, you would remove the OTA from the fork arms.
Subject:	EXT 80 Motor Traninig System Need repair
Sent:	Sunday, April 11, 2010 00:30:12
From:	Ron Harries (
Today, when I was trying to install a switch and plug to us external
power, my drill went too far in and dislodged  the wires to, I believe,
the motor training system. These wires come in two sets. One with three
wires attached to a black device about 1/4 " square. The other two are
attached to a device that is either a LED or some kind of a timing
device. They appear to fit where they have the cogs of a gear between
them. Is it possible for you to direct me to a place on your web site or
any where else that could give me some help.


The motto of this story in "Do Not Use Dull Drills"


Ron Harries
Mike here: Unfortunately, there is no wiring schematic available. If you only cut the wires, can you match the wire colors?


Unfortunately, I did not cut the wires. I pulled the two small devices
that the wires  were connected to away from there position on the scope.
They appear to be attached with hot glue. However, your answer still

Thanks anyway

Ron Harries
Mike here: See the original email "ETX-125EC won't slew right or left" further down this "ETX, General" feedback page as well as the follow-on messages. There is a photo and some discussion of the encoder.
Subject:	7  X 50mm Finder
Sent:	Friday, April 9, 2010 17:03:59
From:	Russell F. Morrow (
I'd just like to know your opinion; do you think an Antares 7 X 50mm
finder scope, at 18.4 oz, would be too much weight for the motors and
gears, etc. of my ETX125AT?


Russ Morrow
Mike here: I have no experience with that finder or ones of comparable weight. But from the comments from others who had added large finderscopes, it could work if you position it with its CG over the fork arm attachment point.


OK; thanks very much.

Russ Morrow

Subject:	Replacement Gear For #1247 focuser?
Sent:	Friday, April 9, 2010 09:51:58
From: (
I am trying to find a replacement spur gear for the 1247 electric
focuser as mine broke in half.  Unfortunately, when I contacted Meade
they could neither provide a replacement nor suggest where to get a
replacement.  Do you or any of your readers have any idea where to get a
replacement?  It it the small, 11 tooth gear that attaches directly to
the electric motor shaft.

Thanks in advance,

Mark Gatman
Mike here: Some possible sources:, Telescope Warehouse (link on the Astronomy Links page), and the article "Replacement Gears source" on the Helpful Information: Telescope Tech Tips page. Let me know how it goes.


I will,  thank you.


Subject:	Meade illuminated reticle
Sent:	Thursday, April 8, 2010 11:10:02
From:	Ludwig Krijgshaftig (
In order to do a more accurate job at motor training and finder
alignment, I have purchased a Meade 12mm illuminated reticle. Since I
did this primarily for my LX200R scope, I chose the wired version of the
reticle, which does not use a battery but plugs into the scope terminal.

Now I have brought this to my ETX-125PE at my dark site and just noticed
that I have been stupid not to go for the wireless (i.e. battery)
version of the reticle as the ETX of course does not have a terminal
outlet for the reticle.

Do you know the voltage used by the LED in this reticle? When I am back
home I can measure the output on my LX200, but I am now just curious if
I can put 12V on this LED without burning it.

Kind regards,
Mike here: The wireless model uses two LR44 (or equivalent) button batteries. Typically, about 1.5V each.
Subject:	ETX alignment vs. ETX manual
Sent:	Thursday, April 8, 2010 11:05:51
From:	Ludwig Krijgshaftig (
My ETX-125PE is currently staying at my dark site in Brazil, at a
latitude of about 22 degrees South. Although I am quite familiar and
successful with the automatic alignment procedure, I had some doubts on
usage in the Southern Hemispere. So, I have once more studied the manual
and came up with a number of questions as well as inconsistencies in the

The manual I am referring to is titled: Instruction Manual, ETX Premier
Edition Telescope Series, AutoStar - LNT - SmartFinder. It has no clear
publication date or version number,  but the copyright on page 3 states
2009 (which is a bit odd, as I downloaded the softcopy of this manual in
October 2008).

Mostly the manual indeed describes the ETX PE with LNT, but sometimes I
think it still refers to the pre-LNT model. Automatic Alignment on page
17 correctly describes the appropriate home position (full CCW until
hard stop) and that the telescope detects true North. It also explains
that the home position for Automatic Alignment is different from the
home position used with One Star and Two Star Alt/Az alignments. So far,
so good.

The Autostar Menu map on page 22 lists under Setup - Align the options
Easy, One Star and Two Star, while in reality the options are Easy,
Automatic, One Star and Two Star.

Finally on page 36 under Advanced Alt/Az Alignment the appropriate home
position is first described correctly (full CCW until hard stop and then
CW until fork above control panel), but then the section on Two Star and
Easy Alignment points again to the home position described on page 17
under Automatic Alignment. This is an error in the manual (at least for
the PE models with LNT).

Then under One Star Alignment on page 37 is stated that the accuracy
depends on how close to the North the telescope is pointed when setting
the Home position. This is also rather odd (and most likely stems from
the manual version for pre-LNT models) as nowhere before or else in the
manual instructions are given to point the telescope to the North
(except in the Appendix on Polar Alignment).

I have read on your wonderful ETX site the alignment instructions that
involve pointing the front leg of the tripod (the one opposite the
latitude adjustment bar) towards the North, even for Automatic Alignment
with LNT.

Now my questions:
1. Do I understand correctly that it is best to place the tripod with
the front leg pointing to the North, even when operating in Alt/Az and
even with the LNT?
2. Does this also apply when operating on the in the Southern Hemispere?
3. What is the difference between Automatic and Easy Alignment?
4. Is Easy Alignment actually useful for LNT models?
5. Why would I use Two Star or One Star alignment on LNT models?

Kind regards,
Mike here: In Alt/Az mounting, you can attach the ETX in one of two directions, 180 degrees different. So, if you want the leg to be on the other side, no problem, in either hemisphere. Auto Align uses the LNT for leveling and north determination. Once that is done, it proceeds te same as with Easy Align. In non-Auto Align, you are responsible for leveling and pointing the telescope to True North. And yes, Easy, One Star, and Two Star alignment modes are perfectly fine to be used on the LNT models. As to why you would use them, they are just alternatives. One Star mode when in Polar mode can help you align the RA axis to the Earth's rotational axis.


Thanks for your quick answers to all my three e-mails. Your e-mail
handling discipline is quite astounding for me. You must spend a lot of
time every day answering all these questions and inquiries, during an
awesome fourteen years now. All this ETX related knowledge packed in
your ever expanding site is really marvelous. Once more I just want to
thank you for pulling all this together.

Following your previous answer above, I do have two more questions.

> In Alt/Az mounting, you can attach the ETX in one of two directions, 180
> degrees different.  So, if you want the leg to be on the other side, no
> problem, in either hemisphere.

OK, I can point the leg forward or backward, so still pointed either
North or South, right?

The Mike Hogan article from 5 July 2006 points out that "the physical
position of the entire assembly (base, and tripod if applicable) should
be oriented so the OTA is pointing in a Westerly direction. The precise
angle is not important; the goal is that the OTA be pointing West of the
Magnetic North Pole. The reasons are technical and beyond the scope of
this procedure."

Again, this implies with the OTA in the Auto Align Home position that
the front tripod leg points either North or South, right?

> In non-Auto Align, you are responsible for leveling and pointing
> the telescope to True North.  And yes, Easy, One Star, and Two Star
> alignment modes are perfectly fine to be used on the LNT models.

Finally, is the difference between Easy and Two Star align that the
alignment stars are selected automatically or manually?

Kind regards,
Mike here: In Alt/Az mode, it doesn't matter which tripod leg is on which side of the telescope. The ETX control panel goes on the west side of the tripod. For more on using the ETX in the Southern Hemisphere, see the Helpful Information: AutoStar Info page. And yes, Easy selects the stars, which you can skip if not visible, and 2 Star you get to pick.
Subject:	ETX125-AT Lens Cap
Sent:	Thursday, April 8, 2010 10:47:28
From:	Russell F. Morrow (
The lens cap that came with my ETX125-AT has two spring loaded tabs
which kind of stick out. I have a dew shield which I would like to store
in the ETX125 case by inverting it and placing it over the correcting
plate, but the tabs make this impossible. I believe Meade used to make a
metal screw in lens cap; any idea where I could get one? If not, any
other ideas?


Russ Morrow
Mike here: Gee, did Meade change the lens cap design on the new ETX-AT models? It used to be a screw-on cap and there were no tabs. As to dewshields, lots of ideas on the Helpful Information: Telescope Tech Tips page.


Yes, apparently Meade changed the lens cap design; it's no longer a
screw on type, at lest not on my ETX, just purchased from; I don't really like the plastic one; it pops off pretty
easily, and, as I said earlier, it makes storing the dew shield in the
case impossible.

Mike here: Grrr. I really liked the screw-on cap.
Subject:	ETX125-AT Optical Finder
Sent:	Thursday, April 8, 2010 10:42:09
From:	Russell F. Morrow (
Thanks for all your work; very helpful site.

My new ETX125-AT came with a red dot finder which works OK, but I'd like
to add an optical finder; the red dot finder has kind of a wrap around
bracket which screws into a threaded hole on the rear of the OTA;
there's another threaded hole on the other side of the rear of the OTA,
but all the finder brackets I've seen are designed to mount onto the
perimeter, not the rear, of the OTA; I'm not sure it's a good idea to
drill and tap holes in the perimeter of the rear cell since it appears
to be plastic. Any ideas?


Russ Morrow
Mike here: You can see various tips about adding a replacement or second finderscope on the Helpful Information: Telescope Tech Tips page. Lots of such articles there.
Sent:	Wednesday, April 7, 2010 16:33:23
From:	Rashad Ujaimi (
i'm in interested to buy this telescope but 1st of all i would like to
know if it's easy to collimate? the reason is that i'm in saudi arabia
and very far from Meade factory, and for sure the telescope will need
collimation once it reach me.

In general i'm ok with collimation and already collimated my 5" newt.
telescope by a laser collimator, but i noticed even the Mat type
telescope does not have front screws for 2ndary mirror adjustment.

i really appreciate your advice, 

best regard

Rashad Ujaimi
Mike here: The ETX can be collimated by the owner but it is not a trivial task. See the "Star Testing and Collimation" section on the Helpful Information: Telescope Tech Tips page.


Thank you mike for your quick answer, 
i'm sure i will stick around your site and build the knowledge before i
even by an ETX.

best regards


Sent:	Wednesday, April 7, 2010 08:59:46
From: (



SERIES 4000 9.7MM & 15MM, AND #126 BARLOW - ABOUT $80)

Mike here: First, please read the Email Etiquette item on the ETX Site Home Page; all CAPS is a pain to read. As to the Azimuth (not DEC) lock lever, you should be able to slide it away from fully locked position. Just use steady pressure on the lever. You may be able to adjust the AutoStar display brightness (assuming that is the problem); you might be able to see the menu on the screen by holding the AutoStar at an angle. As to eyepieces, Celestron likely doesn't include Meade eyepieces in their sets. That said, those eyepieces are a good choice. For more on eyepieces, see the Helpful Information: Buyer/New User Tips page as well as the Accessory Reviews: Eyepieces page.


Thanks for the prompt response!! Just to update you: Great advice,
steady pressure did release the Azimuth lever. Not as lucky with
Autostar, pressing MODE to reset to factory default failed, and need to
see display (which is blank red boxes) to scroll to brightness command.
Should have been more specific, just for the info, product is described
as Meade ETX Celestial Observer Starter Kit, and is a Meade product.
Thanks again for all your help!! Take care, Bryan
ps It's a bit cloudy here in Miami
Mike here: Oops, my bad. I read "CELESTRIAL" as "Celestron". See, reading ALL CAPS is difficult! Glad you got the axis unlocked. If you want to try a fix the AutoStar via software, there are some things you'll need (hardware and software). So let me know if you want to try that.


Thanks again!! I am going to try that most ingenious, brilliant thing
first, changing out all 8 batteries!! If that fails I'll contact you to
see if it pays to try the software fix. (Do the things really "go bad"?
They sure seem sealed/solid state) Take care, Bryan
ps Hope the clouds move on soon!!
Mike here: Normally, the AutoStar won't fail. But it can happen.
Subject:	[none]
Sent:	Saturday, April 3, 2010 18:18:09
From:	Bill (
Well, I am totally lost.  Having read the manual backwards and forwards,
I am totally lost on how to align my scope.

Here is what I do, step by step:

I rotate the scope until it stops and then back so that the fork arm is
over the control panel.

Then I point it North and try to align.

It takes me nowhere..dark sky.  So I have searched with is manually.

So far I have been able to see the moon.  I have used a variety of
lenses but overall, it seems as if it just magnifies the brightest

I purchased a binoviewer and have two 28mm plossl's in there but to no
avail, just magnified dots of light.

I tried a 9mm plossl and a 15, Kellener and I could not focus in on
anything.  The 42 mm Kellener was pretty clear and had good eye relief
but overall I have seen nothing?

The other issue is that the tripod is very shaky.  Totally frustrated on
these beautiful starry nights before black fly season in the Northeast,
Does anyone have any suggestions?
Mike here: First, I was not ignoring your email. I just discovered that it had been rejected two days ago as SPAM and deleted unread due to the missing Subject line. As mentioned on the ETX Site Home Page, please read the "Submittal Guidelines" (Email Etiquette") item on the ETX Home Page. Thanks for understanding. As to alignment, are you using True North or Magnetic North when you point the tube to the north? Is the telescope and mount base level? Oh yeah, it might help to know what model ETX telescope you have. Stars are very distant. So, they appear as "point sources". Most telescopes, even the largest ones when viewing the largest stars, still only show "points of light". However, stars have different colors, which you can see. And of course, the planets (most of them, anyway) will show disks. And there is the Rings of Saturn. And of course, the moon. Many of the brighter nebulae and galaxies will look nice, especially if you have very dark skies. Regarding the tripod, there are some tips on the Helpful Information: Telescope Tech Tips page to reduce vibration or make the tripod a little more steady.


Etx-125 and I am taking it outside and following the set up and turning
it to the north
Mike here: Please re-read my email. Which "north"? Which model ETX-125? AT or PE?


Sorry, magnetic north using the compass.  The model is the AT
Mike here: That could be a source of the pointing error. You need to use True North, which, depending on your location can vary up to about 20 degrees from Magnetic North. If you can see the star Polaris, use it to indicate the position of True North on your northern horizon. Also, be certain you have your location and Daylight Saving settings correct.
Subject:	ETX-60 eyepiece holder not fitting in hole
Sent:	Monday, April 5, 2010 14:25:39
From:	Timothy J. Davis (
I recently purchased a used ETX-60 and am having trouble getting the
eyepiece holder to fit snugly into the telescope body.  It was out when
I purchased it, and not knowing enough about them, didn't think anything
of it.  I called MEADE customer care and they said the eyepiece holder
was not supposed to be removed.  Does anyone know of a way to repair it?
It doesn't appear that anything was broken off inside, but the eyepiece
holder looks more like a barlow lens, as it has MEADE 2X on the side of
it, thumbscrew and a silver tube with a lense attached to the bottom of
it.  Any help would be appreciated.

I was able to view Saturn last night, although I couldn't use anything
smaller than the 25mm lense because of the lense holder problems.  I
could see lines that make the rings, but given photos of other ETX-60
views of Saturn, I wanted to see a greater magnification of it.

BTW: Meade says they will take my ETX-60 and $150.00 and give me a new
ETX-80.  Should I just do that instead?  I paid $60.00 for the ETX-60 on
Mike here: Meade is correct; the eyepiece holder is not designed to be removed. It would seem to have been broken off somehow. If you can not get in re-inserted, you have two choices: take Meade up on their offer or get an ETX "visual back" accessory that allows eyepieces to be used at the rear port on the ETX.
Subject:	re: ETX-125EC won't slew right or left
Sent:	Sunday, April 4, 2010 21:29:57
From:	richard seymour (
D1 on that card is the infrared light-emitting diode used to -sense- the
motor rotation.

If the motor was -operating-, the grease covering it would have caused
the 497 Autostar to report a "Motor Unit Fault". But having grease on it
should not have stopped the smaller hand controller (maybe).

I'm attaching a schematic from Meade's patent which gives a fair
approximation of how the ETX-125 card works, too.

There are -no- fuses on the Meade cards.  It's very easy to fry bits if
you don't know electronics.

have fun
(Click image for full-size version)


Subject:	Regarding "D1" on "ETX-125EC won't slew right or left"
Sent:	Monday, April 5, 2010 20:07:49
From: (
D1 looks like an LED that shines on Q7 on the other side of the slot.
Together they form an optical interrupter circuit - probably used to
detect when one of the drives is in the init position.


From:	Cruz & Nelson Moore (
Hi and thanks, Dick,

I've got a sneaking suspicion that it's already fried, but (!) it isn't
on fire.  Yet! - But I'm persistent so there's hope for fireworks!  :)

Seriously, you are absolutely right; I'm not up to the task.  I was
hoping to find a loose wire or something obvious to me.   If I can find
local electronics whiz then I would take your schematic to them with the
card and see if perhaps they could diagnose it.  I'm not having much
luck finding such a person.

I called Meade Customer Support and they said they had to have the whole
scope to guarantee that it would work, which is understandable.  I'm not
sure how to ship this but I've read "not in peanuts" someplace.

From what I've read on this site, it may not be worth the $$$ to get the
scope repaired to a point that I have to start practicing Voodoo magic
just to keep it operational.

I just want to look at the moon, the sun, and maybe a planet or two.  I
have an interest in photography, but a glance through this scope tells
me I don't have that much patience.  What a wobbly mount!

At this point, after checking ebay and craigslist, these used scopes
seem to be dropping in price.  Then perhaps I can find a cheap
replacement for parts.

I have to wonder (fire-good) if it would be possible to hook the motor
to a switch so it will work on command.  That is, bypass this card
without messing up the other motor. (I assume there's a card for the
other motor)

Thanks again for your help!  
Mike here: Try Telescope Warehouse (link on the Astronomy Links page) for parts. Alternatively, you can mount the ETX OTA on a different tripod; see the Helpful Information: Telescope Tech Tips page for some ideas.
Subject:	can't slew ccw!
Sent:	Sunday, April 4, 2010 18:00:50
From:	Andy & Leah Lancour (
I am messing with the 125 I bought used yesterday in the living room and
I am getting MUF displays. It seems the scope will not slew
counterclockwise, even if I try it manually (via Autostar). I know it
did yesterday as we spent alot of time getting it set to run well before
I bought it. I am not against the hardstop. Any ideas, Mike?
Mike here: Check the batteries are inserted correctly. Check the AutoStar cable connections; unplug and reconnect the ends, or ever reversing the cable can solve the problem. Also, do a CALIBRATE MOTOR (if you can get past the MUF) and then do a TRAIN DRIVES.


Not using batteries. Connections seem ok. Did a calibrate motor, and
scope raised up, slewed clockwise, and stopped. The Autostar reads
Testing motors through this, then reads Calibrate Motors again. That's
it. I can't do a Train drives without slewing.

No apparent problems with gears or broken wires. I also tried to switch
to a both a different Autostar unit and a different cord form my 90, but
it still won't slew CCW.

It almost seems like it thinks it is up against the hardstop.

One other thing I noticed is that the Autostar has "cord wrap" set to
on, which is supposed to be off by default. However I cannot seem to
make it switch off, no matter what buttons I try. That probably means
nothing, though.
Mike here: Cord wrap is just a way for the AutoStar to not rotate too far. Of course, the physical hard stops also prevent this. With the axis unlocked, can you feel any resistance to moving the telescope by hand past where the AutoStar stops slewing? Go slowly and carefully; you don't want to cut a wire if that's the cause of the resistance.


I had opened up the bottom a couple times and everything seems to rotate
fine - no obstructions or wires seem damaged or binding. I wonder if the
LNT is the culprit here. I really don't want it anyway. Is it possible
to pull the entire module and replace it with a standard finder? Or will
Autostar still think I have it and go nuts. The problem with that
theory, though, is that the left arrow (ccw slew) still didn't work when
I tried a different Autostar unit.

The Autostar seems to stop moving no matter where the scope is
place/started from. It will not slew ccw - no matter where the scope is
on the circumference of the base.
Mike here: I doubt that the LNT module is at fault but if you want to disconnect and remove it, you can. Since two AutoStar units have the same problem, I suspect a bad connection, motor, or circuit board problem. But I would suggest disconnecting the external power source and using fresh batteries just to confirm it is not the power supply.


looks like it is headed to Meade for repair - crap
Mike here: Sorry to hear that swapping to internal batteries didn't help.
Subject:	Hi Mike
Sent:	Saturday, April 3, 2010 20:07:40
From:	Ross Elkins (
We spoke 6 months ago about our golden nature guides! I was looking for
a nice 8-10" scope but lost my job last October 1. Patience paid off and
after 6 months of perusing the local Craigslist, I brought home a very
nice ETX 90 EC for $100!!! It came with the additional autostar computer
and the one 26mm eyepiece. Unfortunately, no tripod. I have a couple of
bids on an 883 or 884 on ebay and I've seen a few on craigslist so
something will turn up. I cleaned the eyepiece, mirror and the outside
of the front lens carefully of fingerprints and dust with Dr. Clays
brew. Now for the exciting (for me) news.

On my first night of viewing I perched the 90 on a wooden rail and also
tried holding the whole thing in my hands. Finally I stacked several
full 5gallon paint pails and noticed what looked like a bright star.
When I focused in I noticed rings and voila, it was as you can suspect
the one and only planet Saturn. I was so excited, I called my best
friend, got my wife out to see too and had a lot of fun. I owned some
cheap kids toys telescopes since the day I got that Golden nature guide
and gave up hope that I would ever really see something like Jupiter or
Saturn as more than a bright dot. After that I kind of knew where the
Orion nebula should be and I'm pretty sure I saw it. 4-6 stars and a
faint amount of dust/gas as a backdrop. I put my equipment away feeling
very satisfied and I'm hooked.

My priorities are a couple of additional lenses, a 2x barlow and a/c
adapter or battery pack.

Update, just heard from someone on craigslist with a used 883 for $25! I
think I'll be leaving now to buy it.

I'm back! Got a really nice 883 tripod for $25. Picked up Meade barlow,
12.4, 9.7 and an Orion variable polarizer for $15 each. I'm in business!

Gotta setup the tripod for tonight. Later!

Mike here: Reminder: see the Email Etiquette item on the ETX Site Home Page; your subject wasn't too descriptive. Ah, yes, that first view of Saturn through a telescope. That's something you will never forget! Welcome to a wider universe!!!
Subject:	used scope checks
Sent:	Saturday, April 3, 2010 07:01:27
From:	Andy & Leah Lancour (
Today I am looking at a used 125 and am wondering if there is a way to
check for optical problems during the daytime. It's a long drive and I
want to be efficient in analyzing the scope. However it will not be dark
out (but it's raining anyway) The 125 I had purchased new didn't work
out, so I am hoping this one will. Thanks again
Mike here: Use a low power eyepiece and look at distant objects. Buildings should have straight lines on the sides and windows. If you have a shiny Christmas tree ornament or can find a shiny yard ornament, you can do a "star test". See the article "Star Test in Daylight" on the Helpful Information: Telescope Tech Tips page. Of course, also look at the optical surfaces for evidence of coating damage (ie, smears, scratches, etc.).


Good tips, Thanks Mike.
Mike here: There's more info in the article "Purchasing a Used Telescope" on the Helpful Information: Buyer/New User Tips page.
Subject:	When did UHTC become standard?
Sent:	Friday, April 2, 2010 06:46:03
From:	Andy Lancour (
I know UHTC is standard now, but do you know what year this happened? On
the 125s -Thanks
Andy Lancour
Mike here: I'll have to get back to you. To answer your question will require that I go back through all my Meade catalogs and see which one shows that.


As long as you are doing that, ol' buddy ol' pal, when did they get rid
of the finderscope and replace it with a red dot finder? Thanks, Mike
Mike here: The catalogs I have (through 2007) don't show the changeover of the finderscope nor when UHTC became standard. So, as a guess, I'd say they both occurred in 2008, +/- 1yr.


thanks for your time, Mike

Subject:	ETX-125EC won't slew right or left
Sent:	Thursday, April 1, 2010 11:02:19
From:	Cruz & Nelson Moore (
Recently I was given a Meade ETX-125EC.  Actually, my brother-in-law
gave it to my kids, ages 9 & 11, and I am attempting to figure it out.

I've been taking photos of the moon the past couple of nights using a
controller that has "35-4702-00" written/stamped on the back side. 
Today the left and right slew motors do not function. The up&down slew
functions properly.   I tried a different controller, #497 (I think),
and the left/right slew did not function with it either.

I called Meade customer service, and was told that I would need to send
this in for a $160 repair.  Considering that the scope, tripod, case and
several eyepieces were gifts, I think I can afford the repair.

However, I am curious if I may have done something to disengage the
left/right slew motor, or otherwise damaged the scope out of ignorance. 
Would you be able to advise/comment on this and/or give direction?

Is there another repair service you would recommend over or beside
Thank you,
Mike here: Lets do some Q&A first. Since you indicate that the slewing problem occurs with both handcontrollers, we'll assume the AutoStar (the one with the number keys) isn't at fault at this point. When you slide the azimuth (horizontal) locking lever, does it actually lock the telescope position? That is, if you try to move the telescope tube sideways by hand (gentlely), it doesn't want to move. With the axis unlocked, can you hear the motors in the base running when you press the slew arrow keys? Have you replaced the batteries in the telescope base? (If you have replaced the batteries, be certain to do a CALIBRATE MOTOR from the AutoStar. Also, if you have never done one, you should do a TRAIN DRIVES with the AutoStar, once slewing works.)


Hi, thanks for your response.

When you slide the azimuth (horizontal) locking lever, does it actually
lock the telescope position? Yes.

With the axis unlocked, can you hear the motors in the base running when
you press the slew arrow keys? No.  This motor (horizontal/right/left)
makes no sound when I press the left or right arrow keys.  The
declination/verticle motor and movement/sound appear to work fine.

Have you replaced the batteries in the telescope base? Yes.  However, I
took them out and tried operations with AC converted power, with the
same results.  I performed these tests on AC power.

If you have replaced the batteries, be certain to do a CALIBRATE MOTOR
from the AutoStar. I aligned the tripod and scope, while initializing
Autostar.  This resulted in an error message saying there was a motor

Additionally, when I turn the power switch on the scope's base on with
the controller detached, the vertical motor fires every so often for a
second or two, raising the tube until the viewfinder bracket hits the
fork arm.

I have had the base plate off and could not see any loose wires.
Thanks again for your advice,
Mike here: Did you attach the AC adapter before or after the problem started? Some slight movement is normal with the handcontroller not attached BUT powering on without a handcontroller is NOT recommended. If you can not hear any sound from the motors when slewing in the horizontal direction, then it is likely there is some problem. Either the motor has failed or the circuit board has failed. Just to be certain, have you tried running the motor at different speeds using either handcontroller (with the axis UNLOCKED)?


Did you attach the AC adapter before or after the problem started? 
Just to be certain, have you tried running the motor at different speeds
using either handcontroller (with the axis UNLOCKED)?
Yes. The motor still does not fire.
Mike here: OK, time for a repair. Your choices: Meade or Dr. Clay Sherrod's "Supercharge" Service. Info on the Supercharge is on the ETX Site Home Page.


Ok, thanks a lot, Mike.  

And more:

Took off the cover plate - again.  :)

Vertical motor runs when 4 wire set switched to horizontal switch.  So
the controller ok, and that first card/board inside the case must be ok
(the circuit board you plug the controller, ac power into).  

Then checked resistance in 4 wires going to circuit board below
horizontal gears.  Seems ok.

Then remove circuit board - ETX 125 15-4506-00 REV C.

There weas a gob of grease over "D1". This looks like a fuse? Top had
some black stuff on it - hot grease?  Wiped it off. This "D1" is a
little clear plastic thing that has two little inverted golf clubs
inside.  Are they supposed to be fused together?  These don't appear to

Can I jumper the bottom of the golf clubs and try?  Zzzzzttttt!  Ha ha.
You can tell I didn't pay for this, eh?  And, I've been off work for 9
months - work comp, still getting paid, but that is probably going to
end soon along with the job so I'm looking to save money.  Hence, the
screwdriver approach.

Do you know where I could purchase this card/circuit board.  I read a
similar post on your site and on this one:
sort=& cat=all&page=1

I've attached photos of the board and the "D1" dohinky that was covered
in grease.  Under magnification there is a hint of a gold thread going
between the two "golf clubs".  Hope my terminology isn't too technical
for ya. :)

Thanks again for your advice.




Mike here: Can't answer your electronics questions but you can try Telescope Warehouse (link on the Astronomy Links page) for a replacement board.

And more:

OK, thanks.  I'm only getting .315 volts to the RC drive motor after the
board, and it has 11.97vt to it (black/red).  I plan to call meade
(closed today, Friday April 2) and see if perhaps I can send this board
in for repair other than the entire scope.  In the meantime I will look
for a local eletronics whiz as you suggested earlier.
Thanks again.
Mike here: I doubt that Meade will agree to that.

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