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Last updated: 29 February 2012

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:	ETX 125 rebuild.
Sent:	Monday, February 27, 2012 11:51:25
From:	Mike Morrison-Smith (
You kindly emailed me a few weeks ago about a ETX 125 that I was trying
to repair after a electric fault damaged it.
I thought I would finish the story for your interest.
I purchased from the UK the three circuit boards, motors, gearboxes and
worms. Of course I now know Meade changed their internals and I got the
pre six wired dec circuit board. After much work I am almost there with
a successful outcome. I will not bore you with the full story, but the
original scope parts have been used except the following:

RA circuit board, motor, gearbox. Dec circuit board and motor. Power Circuit board.
I have had both gear boxes apart and the only two things left to do is
get the allen bolt out of the dec worm to move the plastic cog onto the
brass shaft as there is ply in it. And wire up the LNT device to work of
the aux socket. 
This repair has taken a long time, but it has kept me amused. 
I have also put two weights on the end of the OTA to try and balance it
out a bit.
If you wish, I can expand on any area.
Kind regards,

Subject:	70 vs 90
Sent:	Monday, February 27, 2012 10:30:24
From:	Mike Carriere (
Great site.  I have choice between a used ETX70 with Autostar and used
ETX90 without Autostar.  Same price.  Which would you recommend?
-       Mike
Mike here: See my ETX-90 and ETX-70 comments on the Helpful Information: Buyer/New User Tips page. That would help you decide.


I did review that and I'm still not sure.  The Autostar seems pretty
helpful but I'm not sure the images will be very good.  I'm new to this
so would the 90 without Autostar be too difficult or is the clarity
worth it?
Mike here: The AutoStar is useful but not required IF you are willing to learn how to navigate around the night sky. Remember, observers didn't have GOTO telescopes hundreds of years ago and they did pretty good things in astronomy. But if you live where there are light polluted skies, the AutoStar will help you locate faint objects.
As to aperture and focal length differences, yes, the ETX-90 will provide higher magnification. The ETX-70 is more a wide field instrument. But as I always say, the best telescope is the one that gets used. So, if finding your own way around the sky is not for you, then a GOTO telescope will likely get used more. On the other hand, if the views are disappointing to you, then you'll want a larger telescope at some point.


Thank you for the information it is very helpful.  Getting a little lazy
in the "computer does everything for you" world.

Subject:	should i clean or leave as it is
Sent:	Wednesday, February 22, 2012 23:56:47
From:	edward von delelis (
I could see molds growing on the sides of my etx, should clean it or
leave it there ?

Btw, this scope was with "super charge" when I bought It (probably third
hand) , can I still know what were improvements made to this and how old
my telescope is? 






Mike here: Egads. Mold is not good for the coating. It needs to be cleaned. See the article "Cleaning Optics" on the Helpful Information: Buyer/New User Tips page. Before removing the corrector lens, be certain to mark its position so that when you screw it back on you will get it back in the proper position. You may still want to do a "star test" to check it for collimation; see the Helpful Information: Telescope Tech Tips page for more on collimation. As to Dr. Clay Sherrod's Supercharge service, see the "Supercharge Service" link on the ETX Site home page. While the page shows his current service, it will give you an idea of what he does. As to the age of the telescope, it is probably originally bought in 1999 or 2000. You could contact Dr. Clay; he probably has a record of his work on it.

Subject:	CG5 +ETX 90
Sent:	Sunday, February 19, 2012 14:23:11
From:	Steve (
I am looking to attach my ETX 90 to a Celestron CG5, not sure what type
of plate/mount/dovetail I would need.
Any info would be great.
Mike here: Losmandy and ScopeStuff have tube rings and mounting brackets to piggyback the ETX on other telescopes. Links on the Astronomy Links page. Or you can purchase them from your favorite telescope dealer. Alternatively, you could make your own piggyback adapter. There are several articles about that on the Helpful Information: Astrophotography page. If you have a camera piggyback adapter for your Celestron telescope, you can piggyback the ETX-90 OTA using that. I have piggybacked my ETX-90 OTA on an 8" as seen here:

Subject:	ETX-90AT
Sent:	Saturday, February 18, 2012 17:41:22
From:	Angel Ortiz (
I recently purchased the Meade EXT-90AT.  I am new to astronomy and
after much research I decided for cost and features this was the best
fit for me. I have a question, I'm sure the first of many.  The
telescope comes with a 26mm super plossyl eyepiece and a 9.7mm super
plossyl eyepiece.  Are there any other eyepieces that I might want to
add right away?  Also, Should I purchase a dew shield, and if so which
one?  Ray Bassford - Plainfield, NJ. 
Mike here: Welcome to the ETX universe!
See the Helpful Information: Buyer/New User Tips page and the Accessory Reviews: Eyepieces page for some guidance on eyepieces. Keep in mind that every telescope has a theoretical maximum magnification. If you are unsure how to calculate that, see the ETX FAQ page.
As to a dew shield, they can be useful depending on conditions where you live. You can easily make one. See the Helpful Information: Telescope Tech Tips page for several articles on them.

Subject:	Great Job !!!
Sent:	Friday, February 17, 2012 08:29:32
From:	Walter (
Good morning Mr. Weasner,
I just wanted to write and say thanks for taking time to make the page
below available on the internet.
Great job !!!
	Copyright ©2010-11 Michael L. Weasner /
	URL =

Subject:	Lenses & eyepieces
Sent:	Thursday, February 16, 2012 05:40:29
From:	Christian R. Larsen (
Can you recommend any lenses / eyepieces for my ETX-70 which could
provide a better view of the planets?
I have the default set of eyepieces and a 3x Barlow lense.
Mike here: Due to the small aperture and short focal length of the ETX-70, viewing planets will be disappointing to many users. The maximum magnification is going to be limited. For any telescope, the maximum is going to be about twice the aperture in millimeters; 140X for the ETX-70. (See the ETX FAQ page for more on magnification.) Getting close to the maximum will require bright objects and excellent seeing. The eyepieces you have, combined with the 3X Barlow Lens, gets you close to the maximum. You could get a shorter focal length eyepiece but if you really want to do detailed planetary observing, you will need a larger telescope. The ETX-70 makes an excellent wide-field instrument, so it can be a handy telescope to use, as long as you understand its limitations.

Subject:	etx-60 base to etx-80 base
Sent:	Saturday, February 11, 2012 17:00:31
From:	Don Bishop (
Is it possible to switch a Etx-60 base with a Etx-80 base ? 
Gears on 60 work 
gears on 80 don,t
                                   Thanks Don
Mike here: I don't have an ETX-80 to compare but it is likely the tube adapters won't match. It may be easier to replace the gears. There are several articles on ETX gear repair and replacements on the Helpful Information: Telescope Tech Tips page. Can you clarify what's wrong with the ETX-80?


The etx-80 horizontal drive gears are not moving, vertical  works great,
 I have a etx-60 that the motor & gears work great  using the Autostar
controll but the optical tube is damaged, I measured the  distant
between forks and they are exact as the 80 also the base is exact, as
far as taking both apart [60&80] I have the mechanical ability[ and
tools]  but I need instructions or pictures to help me take either
apart, I really want to fix the Etx-80 so any help would be appreciated
                                                                                    Thanks Don
Mike here: See the article "ETX-70AT Repair Guide" on the Helpful Information: Telescope Techs Tips page. That should get you going. I also recommend you read and follow the "Disassembly Procedure" article on the Telescope Tech Tips page.

Subject:	Re: etx spares
Sent:	Saturday, February 11, 2012 12:14:29
hi, the plastic lens onthe LNT module  is it important, what can you not
do without it?
                                                                        sorry to disturb your evening
                                                                          THANKS MICHAEL K..  
Mike here: Good afternoon. The LNT lens is what the red LED dot is projected on to. So it is important if you will be using the SmartFinder to aim the telescope. With the LNT telescope models, the SmartFinder is used during the initial star alignment steps if you plan to use the GOTO capabilities of the AutoStar. HOWEVER, it is not absolutely required to do the star alignments or aim the telescope. You can visually sight along the telescope tube to get in the general area of the selected star (or object) and then slew the telescope using the AutoStar until the star (or object) is centered in the telescope eyepiece. Some people don't like the "1X red dot" style finders (me included) and prefer a magnifying finderscope.

Subject:	ETX 125
Sent:	Monday, February 6, 2012 10:35:00
From:	thomas hutchins (
Hi All , I purchased a ETX 125  recently that had not been taken well
care of . So far Ive cleaned it up and have been able to get the motors
back to working. It is missing the degree band around the bottom so i
don't know where O degree  is  It there and way to mark it with a new
band or even manually creating one ? Umm also the first day i had it on
the tripod it fell over and caused a lil crack in the bottom of the
front lens so also looking for one of those.

Thanks Mike ... Was in AZ last week and the view of the sky was amazing !!!

Sent from my iPad
Mike here: The Right Ascension setting circle tape is not really required unless you plan on using the setting circles to locate objects. If you have the AutoStar, then there is no need for a RA tape. As to replacement corrector lens, that will be more difficult (and costly). But you can try Telescope Warehouse (link on the Astronomy Links page) for both.


Thanks For the info Mike .. I was thinking i needed the RA to first
setup the Autostar. Or do i just point it north ?  It seems that i can
still see things ok with the crack (Only about an 1/4 of and inch and
not all the way thru) I looked at the moon just to check . ill just keep
my eye out to see if anyone pops up with one.. .. I did see the site but
the don't have any lens in stock //
Mike here: Yes, just use True (not Magnetic) North to set up the ETX in the proper Home Position.

Subject:	etx spares
Sent:	Sunday, February 5, 2012 13:25:41
hi, i wonder if you can help me, i need to know how i can get a new
prism i think it is called to aline the autostar of the etx90 i have as
the arm that clips into the ???? on tpo of the scope is not there
"snaped off"  i am totally new to this pass time and am clutching at
straws  i live in the UK.  please advise
                                   thanks michael k.. 
Mike here: Do you mean the finderscope that is on the telescope tube? If so, you can add a finderscope. See the Accessory Reviews: Finderscopes page. If you mean the plastic lens on the LNT module, you might be able to get a replacement from either Meade directly or from Telescope Warehouse (link on the Astronomy Links page).


thanks for responding ust bought scope i think it is plastic piece i
will get back to you later on if thats ok with the exact part ect ok?
                                                 thanks michael k..

And an update:

hi, this is the address for meade spares if you are asked again,  and
thanks for your help
         michael k..

	From: Sales Telescope House (
	Subject: RE: ltn lens
	Date: Monday, 6 February, 2012, 9:48
	Thanks for the email, these are available by phone order,8.50 plus VAT.
	Pete Gallon Sales Manager    BCF Ltd
	Telescope House - Telescope Specialists Since 1785
	2 New Buildings
	Newchapel Road
	RH7 6BA
	01342 837610 
	Please consider the environment - only print this e-mail if absolutely necessary
	-----Original Message-----
		To: Sales Telescope House
		Subject: ltn lens
		hello, i am after a replacement LNT LENS for my etx 90 telescope  please advise 
							thanks michael k..

Subject:	Right Angle Finder for ETX-90EC
Sent:	Wednesday, February 1, 2012 15:50:15
From:	Ted Kowalczyk (
I have been out of the astronomy loop for a few years but have returned
and have decided its time to put a right angle finder on my scope. After
searching the internet it seems the Meade scope #825 is not available
anywhere. Do you know of a right-angle finder scope that would fit
without modification on the EXT-90EC?
Ted Kowalczyk
Mike here: JMI used to sell one but I don't see it listed on their website anymore ( You might email them and see if they still have one.


Thanks Mike! I will check with them.



Here is JMI's response. I think I will just install a mount from Orion
and use one of their finders.  Thanks for your help.



	Sorry. It's been years since we had that item.
	Best Regards,
	Tom Johnston
	Production Manager

Subject:	ETX 80 altitude moves too high during alignment
Sent:	Wednesday, February 1, 2012 09:42:20
From:	maes (
Hope you can help. Cannot see this problem elsewhere on the site.

I have a secondhand ETX80AT refractor. With several failed attempts to
get the scope to align and in case previous owner had a strange set up I
reset the Autostar Fitting new Duracell batteries; correctly entered and
double checked all settings for location, time and date, time zone. I
have also trained the drives. Telescope level and pointing north (Home
position) at start

The problem is when going through the alignment process whether using
the"easy" or "two star" method the azimuth moves to the correct position
but altitude goes 20 to 30 degrees too high no matter which star is used
from the database.

If an alignment star is chosen with a high altitude the scope will move
upwards until it would hit it's vertical stop, if I did not stop it.
Moving the scope to the correct altitude and centring the star leads to
"alignment failure" message. Accepting the "wrong" position without
centring give an "alignment successful" message but of course the
scope is hoplessly off actually locating objects.

A possibly connected problem with the altitude motion is that if using
the telescope manually (ie non aligned) through the controller it does
not stay in position once it is pointed at an object but after a few
seconds will move upwards a degree or so in sharp little jumps.

I hope this is a fixable problem with the scope

best regards

Mike Alexander
Whithorn UK 
Mike here: While you might not find your specific problem discussed, I suspect the "Q. My telescope has gone berserk. It slews until it hits the hard stop in either azimuth or altitude. It behaves erratically. What do I do?" on the ETX FAQ page will cure the problem.


I read that FAQ you suggested but the scope is not "berserk" it very
deliberately goes to a position too high on the alignment star - the az
drive is fine.
I had already done the things suggested by the answer, however as it was
a clear night toight I thought to double check  I would  redo it all

Just so you have it
1) Before I changed any settings the scope went too high in alt.
2) Tonight with new batteries, did the reset, calibrating motors and
trained drives. Location time and date, time zone all set correcty.
Result - it still went too high.
By the way it only tries to hit the alt stop if you align on a star like
Capella (near zenith) but is 30 deg too high on Rigel or Regulus.

Watching the scope movements carefully throughout the alignment process :
From the Home positin the alt drives moves first and seems to reach
approx the correct angle for the selected alignment star.
The az drive then moves to approx the right position too. Both are a few
degrees out but about what you would expect for 1st star in alignment
However instead of stopping at that point the alt drive starts again,
moving the scope to a steeper angle thus over shooting the alignment
star by 30 deg.

There seems to be a repeatable error in altitude motion not a random one
which I cannot account for hence e-mailing you

Hope you have alternative solution - many thanks

all the best

Mike here: OK. I assumed you hadn't done a CALIBRATE MOTOR since your first email said you only did a TRAIN DRIVES. So, now that we know that CALIBRATE MOTOR hasn't cured the problem, we can consider an alternative culprit. It is possible that the altitude drive encoder is dirty. Sometimes it can be cleaned by just unlocking the axis and slowly move the telescope tube up and down, full-range, several times. So, try that next. If that doesn't cure it, check the HBX cable and jack. The pins should be clean, not too depressed nor bent sideways.


Thanks will give that I'll give it a try

My apologies I rewrote the e-mail from a first draft that did include
"calibrate motors" but seemed to have missed it in the version sent to

all the best


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Copyright © 2012 Michael L. Weasner /
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