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Last updated: 30 November 2010
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:	I wanted to provide a resource on space for your page.
Sent:	Tuesday, November 30, 2010 15:04:43
From:	Courtney Goodman (
My name is Courtney Goodman, I am a science teacher, and I am working on
my syllabus for the spring semester.  I have been using your page
( for several semesters now, It
has a lot of great stuff on it!! Thanks so much

While looking for new resources on astronomy I found a great new page: . It
provides a lot of information on space objects, including: planets,
stars, galaxies, moons, etc....  It might be a good addition to your
page as well. Let me know what you think

Have a wonderful day 


Subject:	Weasner Site:ETX-90 eyepiece + filter fit
Sent:	Friday, November 26, 2010 11:25:48
From:	Nohr Tillman (
Hello Herb,
I hope you don't mind that I reply to your e-mail to Mike Weasner
regarding ETX-90 eyepieces and filters.

I own both an ETX-90 and ETX-125. I use Meade eyepieces in both of them.
With the ETX-90, I find that adding any filter causes the assembly to
sit high (bottoming out on the EP tube) and not shoulder on the tube
itself. With the ETX-125, I do not experience this. I think it just a
matter of the compactness of the ETX-90 that the EP tube can handle only
an eyepiece without a filter. If you're getting focus, you should be ok.
Just my experience,
Nohr Tillman
Troy, MI, USA, Earth


From:	Herb Yeates (HY) (
Thanks, Nohr.  Good to hear.  I might try a shim, from a small bit of
plastic or the like, to reduce the wobbliness a tad, but await a clear
night to judge results.   Appreciate your guidance.


- h

Subject:	Book
Sent:	Friday, November 26, 2010 11:12:46
From:	Nohr Tillman (
Hello Sandra,

I hope you don't mind that I responded directly to your e-mail to Mike
Weasner. I have an idea for your Christmas present book.

I am an engineer, interested in astronomy and space travel. I have been
collecting the Apogee Books series of the Apollo missions, edited by
Robert Godwin. Any of these books are great for an engineer's brain
since they provide the NASA reports of how they actually went to the
moon. Also included is a CD-ROM or DVD with pictures and video of the
missions. Personally, I have enjoyed the material for many hours, and it
may be just what you are looking for.
My 0.02,
Nohr Tillman
Troy, MI, USA Earth
Mike here: Good tip! I have several of the Apogee books. Excellent resources and great reading.


I find the Apogee books a good read, even though you'd think they'd be
very dry. I really like the pilot debriefings, brings the human element
into the whole flight.


From:	Sandra Gulla (
Thank you all!

Subject:	ETX-125 Declination Auto Tracking Issue
Sent:	Thursday, November 25, 2010 15:18:52
From:	Martyn Goodwin (
I have recently aquired an ETX-125 PE scope which was in need of a
little TLC. I have rectified a couple of mechanical faults which it had 
sheared DEC travel limit lug on clutch plate  slipping dec clutch  etc.
The scope now seems very smooth in manual commanded slewing. However in
auto tracking the dec axis appears to jump. e.g. when tracking Jupiter,
the planet can be seen moving slowly down the FOV and then jumps back up
(very regular pattern - every 3 secs or so) as though the drive is
sticky  but it isn't - because when I use the autostar up/down buttons
on a speed of "1" this jumping behavior stops. Any suggestions as to
what could be causing this problem? The sound of the drive smooths out
when I manually select the slowest dec slew in either direction (up/dn)
Any links to a fix would be greatly appreciated.
Many Thanks in anticipation
Martyn G (a newbie astronomer!)
Mike here: First, have you done a CALIBRATE MOTOR and TRAIN DRIVES? If not, do those. Second, try redistributing the lubrication by unlocking the axis and slowly move the telescope up and down by hand, from stop to stop. If these don't cure the problem, it could be that the gear mount is slightly loose or the gear is loose on the shaft. You will have to open up the fork arm to check those.


That was quick  thankyou! I've done a train drives but not calibrate
motor. I will check the gearbox mount, but when you say the gear is
loose on the shaft to which shaft in particular do you refer?
I'm in the UK so I'm off to bed now (2100L) cloudy skies and -2C  sheesh!!
Mike here: The gear mount is attached to the board. There have been reports of the gear mount breaking loose. Should be clear here tonight but the low will be -5C (and this is southern Arizona). I plan to be out in the observatory, at least part of the night!


Hmm.. The dec gearbox/motor unit on my model, as far as I can tell, is
mounted with 3 screws direct to the aluminium yoke casting (with small
rubber O rings either side of g'box). I've tried adjusting the tightness
of these, but the only thing that changes is the amount of "slop" going
from up to down. I've also adjusted the worm gear "force" screw and the
end play all to no avail. What I'm trying to do is to get the dec travel
as smooth as the RA (there's MUCH more slop in the RA but at least it's
very smooth). The dec drive sounds OK, it's just that the image is ever
so slightly unstable. Is the dec drive inherently less smooth? I
wouldn't have thought so, but I may be trying to achieve the
unachievable!? I've done all the other things you suggested Mike,
possibly the dec gearbox needs replacing..
Best Regards
PS when I said 2100 I meant 2300L !!  just in case you were wondering 
which you probably weren't !!! It went down to -5C here too  maybe snow
on the way.
Mike here: Did you check that the gear was tight on its shaft and that there were no broken teeth? Yes, the movement should be smooth. If not, there is something catching or not driving properly. Be certain you are not overtightening the axis lock.


The more I think about it, it has to be the gearbox that's at fault.
When I first stripped the dec assy down, I should have known that I
should expect problems. Because I found the dec end stop was free to
engage wherever it wished  with the gear grinding that ensued as a
result  how can I expect there NOT to be problems? The previous owner of
the scope spoke of these "grinding" occurences. Any gear grinding has to
have it's consequences let alone multiple instances. So I think I should
order a replacement gearbox and have done with it
Mike here: Probably a good idea. See the articles "Replacement Gears source" and "Gearbox Replacement" on the Helpful Information: Telescope Tech Tips page.


Yep  "it's the only way to be sure"  quote Sigourney Weaver "Aliens"
(1986 I believe  "Nuke 'em from orbit")

Subject:	Meade etx 125 alignment
Sent:	Wednesday, November 24, 2010 06:26:09
From:	martin gauckwin (
I have a standard etx 125 and I am having great difficulty aligning it.
Do you know of any devices I may purchase that will help me achieve this
before I just go out and buy a gps scope?

Mike here: I assume you mean you have the ETX-125AT model with the AutoStar. I need more information on what you are doing so that I can see where you are having difficulty. What exactly are you doing to set up and align the telescope? As to a GPS telescope, you would still need to align it. The GPS only gets the local date/time/location information. The only telescope that "auto aligns" without the user doing anything is the Meade LS models.


Yes I have an ETX-125AT with Autostar. I use the alignment mate, which
has compass on one side and bubble on the other. Firstly I get the etx
pointed north and then place the level on the tripod top, then, place
the level in the eyepiece socket....and choose easy align. I think I am
choosing the correct two stars. when skewing has finished and the
alignment successful message appears I then click goto an object I can
never see anything?. Thanks for the advice about the LS being GPS, out
of my price range though so I am going to have to soldier on, hopefully
using any advice you can give me. thanks.
Mike here: First, are you using Magnetic North or True North? You need to use True North for the Home Position. Second, if you are getting Alignment Successful, then that means the AutoStar knows the current geometry of the sky for your input date/time/location. So, check that you have them correct, including the Daylight Saving setting for your location. Lastly, have you done a CALIBRATE MOTOR and TRAIN DRIVES? if not, do them. The AutoStar WILL put objects within the field-of-view of the 26mm eyepiece but only if everything is set up correctly. That's true of all GOTO telescopes. For more on doing alignments, see the Helpful Information: AutoStar Info page on the ETX Site.
Subject:	movement / loosiness in optical tube of Meade ETX-70AT
Sent:	Wednesday, November 24, 2010 05:43:27
From:	Erik (
About 2 years ago, I bought a Meade ETX-70AT as a "bargain" in a local
LIDL supermarket. As a youngster, I was an enthousiatic amateur
astronomer and I thougt it might be fun to do some observations with my
kids. At low magnification (like 14 x with the 25 mm occulair) the
images are quite nice, but with stronger magnifications (with the 12 (
30x) or 4 mm (88x) eyepiece) the images blurred. stars show abnormal
colours and show stripes, and planets are not circular anymore. I
thought this just proved that this telescope was just too cheap and had
bad optical parts, but recently I noticed that there is some movement
possible (loosiness) between the two pieces of the telescope tube with
respect to one another, perpendicular to the optical axis if I put some
light pressure on one of the parts.  I think this might cause the
problems with the images, because the lens is not well aligned and not
parralell with the eyepiece. Can you tell me if this problem occurs more
often with this telescope, is it normal that there is movement between
the smaller and the wider tubes with respect to one another and is this
something I can  fix myself or should I send it for repair to Meade (I
still have 3 years of waranty).
Thanks for your Help!
Erik Badings (from the Netherlands)
MIke here: The objective lens housing at the end of the telescope tube does move. That is how objects are focused in the eyepiece. So, are you turning the focus knob after changing the eyepiece? It does take a LOT of full turns to change the focus with some eyepieces.
Subject:	Hyperion EP + filter -- too long?
Sent:	Tuesday, November 23, 2010 08:09:26
From:	Herb Yeates (HY) (
Recently I came upon an old ETX90 EC, and shortly after your marvelous
website.  I've upgraded my EP's to include a nice Baader Hyperion 13mm,
and want to use it with a Baader 'moon and skyglo' neodymium filter.

Unfortunately however when I attach the filter, the EP no longer drops
fully into the eyepiece tube.  The EP + filter appears to rest instead
on a tube inside the scope, and is prone to not sit squarely and/or
wobbles when the EP set screw is tightened.  In short, it appears the
Hyperion EP + filter is too long for the EP tube in this scope.

Any suggestions?  Workarounds?  Am I doing something dumb?

Many thanks for your kind attention.

Mike here: Does the eyepiece still focus? If so, I'd suggest just adding a small piece of plastic to the eyepiece tube as a wedge to hold the eyepiece more securely.


Thanks, Mike.   Yes it does; focusing appears to be fine.  It's just
that with the filter screwed in, the EP doesn't slide all the way into
the tube, so the set screw to keep the EP in place seems to be pressing
on a part of the EP barrel not ideal for steadiness.  Good idea:  I'll
try a small bit of plastic as a 'shim' and see how that does.

Thanks again!



(Your site was a real gem.  We found Meade's documentation to be pretty
sparse to poor.  Your site helped convince me this old ETX was worth
fussing with, and the wife & I have had great fun in recent nights
gazing as a result.)

Subject:	Searching for a book
Sent:	Monday, November 22, 2010 08:38:25
From:	Sandra Gulla (
I've read throught the book reviews and I am still unsure about a
selection for a Christmas gift.

I'm trying to find a good book for someone who is an engineer and more
than an intermediate astronomy buff. The book needs to be somewhat

Any ideas you may offer would be greatly appreciated.
Thank you so much!
Mike here: Check out the Springer "Practical Astronomer" series. There are many advanced books there that should meet your criteria. Click this link to see what Amazon has and if you purchase using the link, you will benefit the ETX Site. Thanks.
Subject:	ET 105
Sent:	Friday, November 19, 2010 12:45:41
From:	Yoh, Michael (
I wrote to you earlier about my ETX 105 and Dual-Axis controller.  How
it worked when I first turned it on and then quit.  I keep wondering if
I got it into Sideral mode and it is moving too slow to see.  Could I
have done this, and could I get it back into the regular mode where it
will move faster to track non-siderial objects.  It just makes no sense
to me.

Mike here: I don't recall there being any speed other than sidereal for the EC handcontroller when tracking. As you suspect, tracking is a very slow movement; it will take 24 hours to completely go around once. You can change the slewing speed with the SPEED button on the EC handcontroller.
Subject:	etx 70 and barlow lenses
Sent:	Friday, November 19, 2010 04:25:15
From:	jim gauge (
i know you are very busy with your excellent site but i could do with a
little bit of advice.

i have an etx70 and already have a short 2x barlow lens woulld there be
any advantage in me buying a 3 x barlow or would it stretch the limits
of the etx 70 too much?

your advice as always would be very welcome

clear skies
Mike here: As long as you keep the resulting magnification less than the theoretical maximum magnification for the ETX-70, the views will be OK. If you are not certain how to calculate the max magnification for a telescope, see the ETX FAQ. Also, be certain you get a "shorty" style Barlow Lens, otherwise you may not be able to reach a focus with some or all of your eyepieces. One last point; the small aperture of the ETX-70 will mean that as you increase the magnification, objects will become fainter to your eye. At the highest magnifications, this will mean that only the brighter objects will benefit from high magnifications.


many thanks for the quick response and sound advice

Subject:	Meade ETX-90EC
Sent:	Wednesday, November 17, 2010 17:42:48
From: (
I am considering buying a Meade ETX-90EC. Is there more than one full
size tripod that will work with this model? I hate to spend $200 on the
#884 if there is another one for less money that will work with it. Also
what accessories would you recommend for this model?
Thank you very much.
Mike here: I take it you mean a used ETX-90EC since the #884 tripod comes with the ETX-90AT model. You can use some other tripods with the additional of an "ETX adapter plate". You may or may not be able to easily find such an adapter plate. As to accessories, first you need to decide just how you plan to use the telescope, then you can decide on some accessories. However, a good initial accessory is a 2X Barlow Lens ("shorty" style).
Subject:	Newbie question about ETX telescopes
Sent:	Friday, November 12, 2010 15:00:08
From:	n2xwv (
Hello Mike and hope all is well your way,and love the site, I have a
question that may be considered dumb but as a newbie i have to ask, I
have been enjoying a etx-90pe and want to know if i jump up to a etx-125
if it is a worthwhile jump or is there not a big difference between the
two? The wife has offered to buy a new etx-125 for xmas if i want it.
The difference in focal length looks like quite a bit.
Thanks john 
Mike here: There are two big differences. Aperture and focal length. The larger aperture will let you see fainter objects and more details. The longer focal length, combined with the larger aperture, will yield higher effective magnifications. Of course, the downside of a larger telescope is that it is larger and so slightly less portable than the ETX-90.
Subject:	Help with ETX 105
Sent:	Thursday, November 11, 2010 05:58:48
From:	Yoh, Michael (
I just recently purchased a nice used EXT 105 on a Meade tripod for a
really decent price.  Only problem was it did not have a controller with
it, so it was purchased wit the hope that the motors worked.   I
purchased a new Meade Dual-Axis controller on EBAY.

Here's the problem.  I plugged in the controller and it worked. Up,
down,right,left, speed.   However, I changed the batteries and then the
controller did not work.  It lights up but will not move the telescope. 
I thought maybe the mode got changed and read how to set the mode, but
it does not react the way it should.  It says when it first turns on the
four speed leds fast flash and you should push the mode button while
these are flashing.  The top two LEDS should light up.  However, the top
three light up when I do this and then after a short time, the top one
stays on and the others go out.  I can change the speeds, but there is
no movement whatsoever.   I was hoping Meade would tell me there is some
sort of default reset that may get this working again.  HE said this
controller won't work on the ETX105.  Kind of strange it talks about it
in the instruction manual.  I don't hear any motor action, clicking, or
anything.  Am I missing something simple?

The voltage with the new batteries is fine  12.6 volts app.   I did read
about the screws at the bottom of the controller, but it appears that
both of these screws are out, which should give me control.

Any ideas? I'm really frustrated.   I don't really want to return the
controller unless it is defective.  I just keep thinking I am in some
wrong mode that I can't recover from.  I would even buy an Autostar
perhaps, but I need to find out if it is the controller or telescope
that is the problem, or if it is some sort of reset.

Meade does not service the ETX 105 anymore and I can get by without a
controller if need be- still a nice scope, but darn it should work.
Mike here: From your description, it sounds like you purchased the standard EC Handcontroller. What you really want to use is the AutoStar #497, which will provide Alt/Az tracking and GOTO capabilities. The EC controller "should" work so if it doesn't, it is hard to determine whether the ETX or the handcontroller is at fault. When you changed the ETX batteries, did you ensure they were all inserted correctly? It almost sounds like a low power problem.


The instruction manual shows the ETX 105 working with the Dual-Axis
controller and even talks about changing the mode settings.  There were
old batteries in the unit when I bought it, but the unit worked when I
tested the controller I had just purchased.  I tried the horizontal and
vertical control, and the speed setting button.  All worked.  When I
opened the battery housing I saw some battery corrosion, so I removed
the old batteries and cleaned the contacts and put in a new set of
batteries.  Didn't work.  Controller lights up, can change the speed
settings, but no movement.  Battery voltage is about 12.5 volts.  I just
keep thinking I messed up the mode settings or something.  I may have to
have my electronics engineer look at it.

MIke here: As I said, the EC handcontroller SHOULD work. However, now I wonder if you might have damaged something when cleaning out the battery box corrosion. As I indicated earlier, the problem you are having almost sounds like a low power problem. So, check that all the battery compartment leads and connections are OK.
Subject:	ETX-90 vs. ETX-125
Sent:	Tuesday, November 9, 2010 13:35:56
From:	Steve Baker (
I have a question, although I think I may have found the answer on your
site, I simply need verification. After all, it's gonna be a lot of

I currently have an ETX-90, that had the famous problem with the right
fork.  I replaced that from a fellow in Meadview Arizona, (Bill Vorce),
and it's working fine now.  However, I'm interested in
purchasing/upgrading to an ETX 125, and would like to know if it has the
same problem.  I believe if I've read your articles correctly, the 125
(newer model, after about 2002) has aluminum forks, and a much more
stable locking mechanism.  Is this true? Do I have to worry about the
locking mechanism failing on the 125?

Mike here: The ETX-125 has many improvements over earlier models in the ETX line. Of course, it is still possible to overtighten the axis locks (either one) had break or damage the mechanism. But under normal use, you should not have any problem.


Thank you so much for the quick reply. Looks like my wallet is gonna
take another hit, now, to find one of the "new" aluminum models... :-)
Mike here: Use a good dealer.
Subject:	ETX-80 Finder Scope
Sent:	Monday, November 8, 2010 18:57:01
From:	Lora&Andrea (
Just purchased my son his first real telescope from the Meade Factory
Outlet.  It is a ETX-80 but it doesn't have the option of a finder
Is it possible to fit one to the scope with some modifications.
PS  Great web site and will be back.
Mike here: The ETX-80 (and ETX-60 and ETX-70) are such wide field instruments, that Meade decided to not include a finderscope. However, you can add one. See the Accessory Reviews: Finderscopes page for some of the available choices. And there are lots of articles on adding finderscopes to the ETX telescopes on the Helpful Information: Telescope Tech Tips page.
Subject:	Other Eyepieces for the ETX?
Sent:	Thursday, November 4, 2010 13:25:11
From:	Steve Baker (
Hi there! First, thanks for the help on my previous problem, (the
infamous "right fork" thing.

Now, being no stranger to telescopes, I am somewhat of a newbie on the
ETX series, having purchased this ETX90 for a more portable, "take
along" scope when I'm away from my main telescope.

However, having the two scopes, brings up a question.  The ETX is a LOT
smaller, and lighter than my other system, a Celestron C8-SGT, with the
Advanced German Equatorial Mount.  I have a couple of lenses that I use
with that scope, that are not the "normal" small lenses one finds with
the ETX, namely, a Baader Hyperion 26mm, and a Meade 5000 Ultra Wide
Angle 6.? Mm.  As you probably know, these are not small lenses, and
weigh in at a hefty weight.  The question is, is the ETX mount up to
holding these, or should I look at a smaller, lighter lens, while
attempting to maintain the quality of the above lenses?

Any input is welcome, as are opinions, valid or not.. :-)
Mike here: The ETX-90 can probably handle the eyepieces. Just be certain you don't overtighten the axis locks if you do see any slippage. If there is slippage and you want to use the heavier eyepeices, then you can add a counterweight system (lots of tips on that on the Helpful Information: Astrophotography page). Of course, the heavier eyepieces may not be the best eyepieces for a "take along" portable telescope; you might want to consider some lighter eyepieces.


True story, my favorite is the Baader Hyperion, and I plan on purchasing
others.  That leaves several other "older" eyepieces from the Celestron.
One, a 10mm Super Plossel of Meade, I do like.  I think I'll take your
advice, and use the "big" eyepieces on the "big" system.. :-)  That's
what I was thinking, just wanted confirmation I guess.
Thanks again!

Subject:	Plugged my ETX90 w/LNT Hand Controller into another telescope.
Sent:	Wednesday, November 3, 2010 19:07:38
From:	David Iverson (
I was helping a friend with their cheaper Meade telescope, and I plugged
my hand controller into their scope to see if the problem was their hand

Now, when I plug my hand controller into my ETX90 with LNT, the LNT part
seems to be totally missing.  I can manually level it and point it at
north, and get it to allign.  In fact, it actually seems easier to
set-up in this mode. But I am concerned that the LNT module is missing,
and it won't auto-find level and north.  Can I get back the LNT?  Any

Thanks for your help.

Mike here: Have you tried doing a RESET? You will have to re-enter your location, Daylight Saving setting, do a CALIBRATE MOTOR, TRAIN DRIVES, and possibly redo the CALIBRATE SENSOR steps.

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