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Last updated: 20 September 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:	I have broken my red dot finder and can't find a new one that fits! ETX125
Sent:	Thursday, September 20, 2012 03:28:32
From:	Christopher Mancrief (
Hello, this is my first time here, having recently acquired an ETX125AT
but I will be doing a lot of reading I think. Due some clumsiness by me
the dovetail clamp on the red dot finder of my ETX125 has broken. The
mounting for it is undamaged. I have tried to get a replacement but the
dovetail at the top of the mount seems to be a lot narrower than the
norm and all the finders I have tried have been way too loose and I
don't fancy the idea of packing it out, I want something that fits
properly. The broken finder is the same as the one shown in my 2009
manual.  I have tried using the clamps off other finders but the spacing
of the bolts is always wrong. I am getting nowhere fast and would
appreciate suggestions on what to do next. Thanks.
Mike here: Have you tried to get a replacement LNT/SmartFinder module? Try Telescope Warehouse (link on the Astronomy Links page). As to an alternative finderscope, you would have to use one of the techniques mentioned on the Accessory Reviews: Finderscopes page or on the Helpful Information: Telescope Tech Tips page.

Subject:	ETX-105
Sent:	Saturday, September 15, 2012 13:39:31
From:	dorothy yoh (
Okay, I'm hoping you can help with this.  My wife tripped on the tripod
leg of my ETX-105 and it fell over.  Knocked loose the eyepiece tube but
I was able to press it back in firmly.  However, when I focus on a star
and turn the focusing knob the star wanders about a bit in the finder,
from center to off to the side a bit then back to center when you turn
the know.
I figured to disassemble the scope and clean the mirror while looking
for anything loose that would cause this.  I downloaded Doc G's article
from your site and have the barrel out of the mount.  However, his
article is not clear on how to remove the back plate with mirror.  There
are three flat head hex screws with loctite on the back, and three
non-headed allen screws, but I don't think any of these actually are for
removing the back.  It almost looks like it should unscrew, but I'm not
sure.   Doc G's shows the back off, but doesn't tell how to get it off. 
I see no screws into the side of the barrel to hold it.
Before I just put it back together and use it as is, any help would be
Mike Yoh


Mike here: Why do you want to clean the mirror, and possibly damaging it in the process? I suspect the image shift is due to the optics being out of collimation from the fall. I'd suggest reassembling everything and do a star test. If collimation is the issue, that will become very apparent. For more on star testing and collimation, see the Helpful Information: Telescope Tech Tips page.

Subject:	ETX 125 decision
Sent:	Friday, September 14, 2012 20:56:27
From:	Max Byerly (
I bought a ETX 125 last week for $250, and I had some problems with it.
The RA motor would not work, and there was a lot of backlash in the RA
gear. So, I fixed all the problems, but now the declination drive
doesn't work because the little wires that go down through the bottom,
got torn off around the top of the bolt somehow. So I have a decision to
make and I'm looking for some help or suggestions of what you guys think
I should do with it.

First of all, I should start out by saying that this scope was intended
to be used as a quick grab and go, for casual lunar and planetary
viewing and occasionally deep sky or double stars.

I can have it sent back to Meade for $150 plus shipping, but with all
the issues with tracking and goto accuracy, I don't know if that's the
right move.

I could just sell the OTA separate and sell the mount for the parts. 

Or I could keep the OTA and put it on another mount. I'd prefer it to be
a goto and track, and I was thinking an iOptron cube or tower of some
sort but I've heard mixed things there too. 

So, in this situation, if it were you, what would probably do?

Mike here: Hi from my observatory.
Have you tried to repair the wires? Seems like it could be an easy fix to splice in some extra wires. As to AutoStar problems, don't forget the CALIBRATE MOTOR and TRAIN DRIVES steps.


I have, but they won't go back in right and the plastic casing on the
top is not going back. A zip tie would be perfect. You think I should
try and fix it?


Sent from my white iPad 2
Mike here: Yep.


Ok, I took the OTA off and I need to get the plastic top that the bolt
comes through off. You know the one in the top of the base. Do you know
how to get this off. The minute I do, I can fix it easily

Mike here: I'm not certain what part you mean but there are many disassembly articles on the Helpful Information: Telescope Tech Tips page.

Subject:	Re: ETX Bracket for 8x25 Rt angle Finder
Sent:	Friday, September 14, 2012 10:02:14
From: (
I am still messing with  this ETX125 I  forgot what you said about
sending Dr. Clay photos I sent some but they were to large. How do I get
them smaller he just needs  2 photos but do no no how to re size them 
on my computer ???  Thanks Jim
Mike here: You need to use an application on your computer to edit the file size (JPEG compression and/or image dimensions). I use the excellent GraphicConverter on my Mac. You can also use Preview (standard with OS X). I'm sure there are useful programs on Windows that can do resizing but I have no experience with any.


Hewres my ablum at Photo bucket with the pics for Clay.
Mike here: Let me know what he has to say. I haven't disassembled my ETX but in looking at the Tube Adapters in your photos, the left one appears to be different than the right one. Could they have been reversed on the forks?


They are different Mike . But they are exactly how the OTA came out.
They were snapped in and I pyned  to pull the OTA out . All worked fine
till the terrible day the little screw fell below the fip mirror.    Jim
Mike here: Hi from my observatory.
Hopefully, Dr Clay will be able resolve it.

And this:

From:	P. Clay Sherrod (
Please understand that I am not going to argue about this; both Mike and
I attempted to assist you; I do not think that Mr. Weasner intended for
you to "pry" with a screwdriver or tool as it appears you have done.  I
have told you what I think the problem may be but it was not what you
wanted to hear.
You need to refrain from "shooting the messenger" when people are trying
to help you.
By prying with a tool you have slightly warped the OTA adapter(s) out of
square to the pegs on the OTA and it is going to take just the right
position for it to lock back in....not brute force, not any tool and not
excessive pressure.  At one place, and one place only, will the OTA find
all three of the guideposts that are required for it to lock into place;
as I have said it is very important to set the RIGHT side first and
leave the clutch unlocked with NO screws in place and then gently work
on the left side to get it to find position.
Dr. Clay
Arkansas Sky Observatories
MPC H45 - Petit Jean Mountain South
MPC H41 - Petit Jean Mountain
MPC H43 - Conway West

Subject:	Re: Fiesty ETX90
Sent:	Thursday, September 13, 2012 14:49:01
From:	Patrick Horan (

Subject:	Re: Fiesty ETX90
Sent:	Monday, September 10, 2012 06:20:01
From:	Patrick Horan (
I did remember your calibrate advice, I've done that. Should I do that
every time I take it out, even if I will only be using batteries from
now on?

My next investment is a dew shield, thanks so much for the leads on how
to make one, I appreciate it.

Last night it didn't clear up till 2:00am, humidity 93%. The scope
lasted about 5 minutes before it started whizzing around on it's own,
and that was the end of that. Without exaggeration, the minute I brought
it inside, it did not do that anymore.

You're right, humidity levels that high are bound to be a nuisance in
more ways than one.

Y'know, as if the clouds don't limit this hobby enough as it is, now on
a clear night, I have to check humidity levels too!



Do you own, or have you ever owned an ETX125? Is it worth upgrading to?
Mike here: See my ETX-125 comments on the Helpful Information: Buyer/New User Tips page. I still use it, as reported on my Cassiopeia Observatory reports.


Of course.

Btw, Cassiopeia is quickly becoming one of my favorite constellations.
There's alot going on in that region!

Ok, have a great day, and thanks again.  

One more thing - you've been up, you've probably seen alot of strange
things at night. In your experience, have you ever seen what looked like
a typical satellite, perhaps slightly larger, glowing on and off in aprx
3 second intervals (gradually illuminate and gradually dim again)? This
one rose in the northern horizon and rode along the milky way all the
way to the southern horizon. Directly overhead was the only time it
stopped 'glowing'. The whole process took about 3-5 minutes.

We've all seen satellites, but have you ever seen one illuminate in this
Mike here: Tumbling satellites, typically rocket boosters, can show that behavior.


That makes perfect sense. When it went out overhead it was because there
was little or no surface to reflect the light.
Speaking of which, what source of light created this illumination? It
was directly overhead. Could it have been the sun at 3am?
Mike here: Depending on the satellite altitude, it can be illuminated by the sun for much of its orbit or for only a portion of its orbit.

Subject:	ETX 125
Sent:	Saturday, September 8, 2012 22:33:43
From:	Max Byerly (
I picked up a ETX 125 PE for $270 today and I have to admit, not bad for
$270, but its got a lot of issues that maybe you can help. 

1. Rubber banding from the Autostar (version 4.3Ea)
2. 2 degrees of declination flip (this is a big issue, you can't focus without it bouncing)
3. RA drive doesn't engage immediately when the gears move

Hopefully you can help me with these problems. 

Sent from my white iPad 2
Mike here: Since the telescope is used (I assume), I'd suggest first doing a RESET. Then do a CALIBRATE MOTOR and then TRAIN DRIVES (on both axes). That should solve #1 and perhaps #3. You might also consider updating to 4.3Eg (best version for the old #497 AutoStar). You may be able to tighten up the DEC axis (#2); there are several articles on DEC mods on the Helpful Information: Telescope Tech Tips page.

Subject:	Re: ETX Bracket for 8x25 Rt angle Finder
Sent:	Thursday, September 6, 2012 16:58:31
From: (
Well Mike this is now the 3rd maybe fourth week and hours of
of messing with this. I sould have left to screw in the bottom of the
black plactic deal below the lift mirror. I have tried and tried to
aignthis tube so l the right acesion arm fits   snapps into the  slot.
Left arm no pobblem. I am doing this by myself so its easy!    Jim
Mike here: Unless something is damaged, it should have just worked.


It came off just fine? I dont know what could have changed ? Why is the
left arm going on so easy?  
Mike here: Have you tried reversing the re-mounting? Don't let the left side snap in until the right side does (if it does).


Good idea! I will try it! Thanks!   Jim

Subject:	Fiesty ETX90
Sent:	Tuesday, September 4, 2012 21:38:59
From:	Patrick Horan (
I don't know if you recall but I was/am having electrical issues with my
ETX90 which seem to be related to high levels of humidity/moisture (80%+
@ dew point).  Which power source I use isn't making a difference. It
slews on its own in all directions.  
It seems to me the only way they can fix this is to practically
waterproof it which I don't see happening. I've only had this scope
about two months. I already had to repair a broken wire inside the
spotter scope to re-light the failed LED as well.   

Meade has issued me a return for repair auth which is active for 60
days but I am hesitant to send it back. Should I return it and assume
the risks of all that, or just use it when I know it will work? It's a
sensitive intrument, maybe things like this should be expected? 

What would you do? I'm trying to enjoy it, not get it lost in the mail.
I know there's insurance but it's still a hassle. Being able to afford
one was a long time in the making, I don't want to give it back!  lol 
Mike here: As I said last month, I haven't seen such a humidity related problem reported in the past. That's not to say that it can't happen, as you seem to be experiencing. As I said then, some exposed wire or connection could be the culprit. Of course, determining where that problem is might be difficult, for you OR Meade. Since lots of moisture causes observing problems (dew, corrosion, poor seeing), perhaps you would be better off (and save some money) by using it when the humidity is lower. You have 60 days to decide. Use the telescope when the humidity is lower (assuming it does get lower as the season changes). One problem that does come to mind is the handcontroller. If a contact inside the controller is flakey, high levels of moisture MIGHT cause problems by creating a contact or lack of a proper contact. Trying another handcontroller (if you can borrow one from a local astronomy club or dealer) might indicate whether or not that is the problem. Same with the HBX cable.


Thank you. I thought about a damp controller also, given its fragility.
The 9v power terminal might get damp as well, as it is relatively
exposed. If the moisture levels were any higher it would be the
equivalent of using it in the rain. I don't think that would work out
too well for anyone's 'scope!

This one is for the books. Warm summer evening moisture levels seem ok,
but cooler, dewey autumn evening moisture so far has wreaked havoc. I'm
still learning what conditions it can handle by trial and error. Maybe
when it gets colder, clearer, and drier it will return to normal.

It performed wonderfully on 'blue moon' night, so it's not exactly
broken. I took my first picture, let me know if you'd like to see it.
For an amateur and a hand held sanyo camera it came out really good.   

I like your point here; "Since lots of moisture causes observing
problems (dew, corrosion, poor seeing), perhaps you would be better off
(and save some money) by using it when the humidity is lower".
They can't have it back, hehe.  I'm still in 'wait and see' mode, I
can't help it. Still experimenting...  
Mike here: If you want to try cleaning the AutoStar, see the article "Keypad Cleaning/Repair" on the Helpful Information: AutoStar Info page. BUT, one thing you said bothers me: "The 9v power terminal..." The ETX requires 12VDC and 1500mA for reliable operation.


The adaptor is 12 vdc/1000mA. I had the rep at Meade read me the output
data on the back of their 546 adaptor which my scope requires. I read my
aftermarket version and they matched. But what if it is 500mA short?
What happens? 
The thing runs almost twice as fast when plugged in and pretty loud but
at this point I don't mind if I never use AC power again.
A few moments ago I was viewing the ring nebula, the scope is working
great. Humidity 93%, temp 67, dew point 65. 
Mike here: The Meade Universal Power Supply is 2500mA (I believe) and works with all their telescopes. The original power adapter (#541) for the ETX-90/105/125 was 1500mA. I'd suggest 1500mA for reliable operation.


I don't even want to deal with AC power at all. It's gets loud and quiet
mode is too slow. Plus I feel someone will go flying over the black wire
in the dark sooner or later.

Last night the conditions were worse than during the nights it had
failed but there were a couple of barely noticeable hiccups. It held
it's own for an hour and a half until the glass became too wet. 

That's ok, I'll just remain terrified that every time I boot it up it
could either go horribly wrong or delightfully well, especially if I
have someone over!  

By the way, am I the only genius that figured out that if you'e already
aligned and disorient the scope by hitting enter at the wrong time, one
can manually slew to a known object and synchronize which will re-orient
the scope.

Do I get a 'helpful hint of the week' award for that one or has that
ground been well-covered? :  }
Mike here: Actually, there should be no speed or noise difference in AC vs batteries. Be certain you have done a CALIBRATE MOTOR when changing the power source. Letting the telescope dew up is not a good idea. But let it air dry inside. To avoid dew, add a dew shield. You can easily make one. See the Helpful Information: Telescope Tech Tips page. As to SYNCing on an object, that is a standard technique to align the AutoStar to improve the alignment IN THAT AREA of the sky. But use only fixed objects and not the moon or planets.

Subject:	Re   ETX 105 RA Sticking
Sent:	Tuesday, September 4, 2012 06:44:27
From:	Ron (
I don't know if this will help but my ETX 125 PE motor board and gear
train has some very small O-Rings under the board where the screws
attach the board to the aluminum casting.  They are mentioned in the
article in Tech Tips under Analysis of ETX 125 PE.  While not a PE,  the
105 may have had the O-rings at one time too.  They are very small and
can get lost vey easily.  They give some spacing and allow the board and
gear train to flex as needed.  I tightened the screw just enough to seat
the board against the O-Rings but not squash them.

One other thing is when I had my ETX125PE apart I found the worm gear
was tight in its carrier from the factory.  I loosened it (they used
loc-tite substance at the factory) then reset it to what I felt was a
good fit but not as tight.



From:	Max Byerly (
How do I loosen the worm gear. That is extremely tight, like you were
saying about yours Ron. All the tension comes from when you put the worm
gear in its holder and tightened the screws. And yes those rubber
washers are in place 


Sent from my iPhone

And an update:

So, I think I fixed it. The problem was resolved when I adjusted the two
allen screws that are behind the worm gear on the side of the mounting
bracket. Once I adjusted this, the tension went away and the motor
quoted up. I adjusted it enough that there wasn't any slop, but doesn't
strain the motor and gears. Everything is smooth moving now and seems to
work good. I'll have to try it out under the sky later this week when it
clears. Thanks again for all the help. I saw those screws last night,
but I didn't think I should adjust them, and sure enough that was the
problem. Thanks for contacting your fellow ETXer. He really helped a

Thanks again


Sent from my white iPad 2

Subject:	Re: ETX 105 RA sticking
Sent:	Sunday, September 2, 2012 13:43:22
From:	Max Byerly (
Well I was able to fix it and try it out under the starry night. I
noticed though the accuracy is not nearly as good as it used to be.
Every object was in the field of my 26mm eyepiece, but not now. It will
sometimes out it in the corner, or not in the field at all. I also
noticed the motor sounds a lot noise than before and at certain spots
sounds like it strains more, maybe I put the gears or something in a
little to tight. Any ideas why my accuracy is compromised since I fixed

Thanks again


Sent from my white iPad 2
Mike here: Have you redone the CALIBRATE MOTOR and TRAIN DRIVES?


Mike here: If the gears sound like they are straining, they probably are. Check their alignment and bracket tightness.


Ok, I pulled it apart, looked at all the gear individually. I removed
all the gears from the housing, inspected all of them cleaned them and
put everything back in the way it should. The shaft go certain ways and
I made sure of all that. They all mesh just right. Then I put it back in
the RA drive, everything looks good, so tighten all the screws that hold
everything in and again it sounds like motor or gears are straining.
What I don't understand is if you don't have those 2 screws that hold
the gear box firmly to the base, it sounds fine. I can't seem to see the
Mike here: Can you elaborate on that statement (about the two screws)?


When you put the gearbox in the RA base, you have the two screws that
attach it firmly in there. When you do, that's when you get this
straining sound. If you take them out amid the gearbox is free, but the
worm gear is still attach, that entire gearbox will tilt when the motor
is trying to move the scope. But when you tighten those screws and you
secure the gearbox in the base, that's when I'm getting these sounds.
And you cannot operate the scope without that gearbox being firmly
tightened in there. 

Mike here: Two thoughts: the gearbox is cracked (has been reported occasionally by others), or the mounting angle is somehow incorrect or applying too much pressure on the other gear when tightened down.


Also, if you try to move the gears by hand, the large spur gear, if
you turn it to the right a little and you let go, it will move back to
the left a little bit. It retracts back, and the same if you do it to
the right, it will come back to the right.
Mike here: Tension-created. Lubrication issue?


I don't see any cracks, so how would I fix the angle?
Mike here: If the angle is wrong for some reason, you would have to insert some sort of shim to change that angle. Of course, if that's the problem, determining the "proper" angle could take lots of trial-n-error experimentation.


I'm just trying the think of what could cause tension. Would lubricant help?

Mike here: I'd think if lubrication (is in lack of) the problem would be more prevalent and not just at some points in the rotation. I think we may have done this before, but if not, try it. Unlock the axis and slowly rotate the telescope from hard stop to hard stop (almost twice around), back and forth several times. See if you can detect any resistence. If that test is OK, with the axis still unlocked, run the motor at slow, fast, and fastest speeds; see if you can detect any "straining" in the motor.


What would be the best lubricant to put on it. I don't have any lube, I
used to from my Peterson Upgrades I did on my 7" LX200GPS Mak, but not
now. What would be the best stuff to put on everything in there?
Mike here: Most people have successfully used lithium grease in a VERY VERY small amount. Keep it away from the optical encoders. By the way, how'd the tests go?

And more:

Well I greased all the gears and there is any broken teeth or anything.
If you have the whole assembly out and in your hand, you can run the
motor and it sounds fine. But the minute you put the worm gear in its
slot and tighten it down, that's when it happens. 
So, I wonder why it's doing it, everything is in the way it should. It's
like the tension is coming from the worm gear.

Mike here: Got me stumped.

Subject:	ETX Finder Scope alignment screws
Sent:	Sunday, September 2, 2012 07:07:55
From:	Grebnesi (
I bought a used Meade ETX-105 on eBay. The scope is fine, BUT the
plastic screws that hold and adjust the finder scope are so deformed I
can't use them. The finder was not mounted when this was shipped (very
well packed) but somewhere along the way these screws got badly bent.
Where can I buy identical replacements?

thank you,

Mike Isenberg
Alamogordo, NM
Mike here: Check
Thanks for the link for the screws.

Subject:	884 tripod configuration question?
Sent:	Saturday, September 1, 2012 10:03:25
From:	john (
My question is,I bought a real nice condition 884 tripod on ebay it is
real nice condition,  I bought it because the one on my etx-125AT is not
in the best shape, problem is the mounting screw's on the old one are
inline with the latitude adjustment leg, the new tripod the mounting
holes are horizontal to the north facing adjustment leg. I never saw
this before? Can I still use it on the etx-125?? And how do I align
it??. Got me stumped here. Thanks john
Mike here: I have two #884 tripods and both have the mounting bolts inline with the platform tilt axis. One bolt is between the pivot bolts and the other near the latitude adjustment rod. If yours is different, I'd say it was defective. Or perhaps it was NOT designed for the ETX. Does it have a "Meade" label by the latitude adjustment lock?


I have taken a couple of small size pics of the mounting plate of this
weird tripod config, It is a meade tripod,the hole spacing is right, the
etx-125 mounts up good, the casting show that the bolts are drilled
through the beefed up area of the casting??

I am going to try to contact the seller about this and try to find out
what scope it came with. Seeya john


Mike here: I'd say it is NOT a Meade tripod. See the photos on the Accessory Reviews: Tripods page (low res). They show the "Meade" name by the altitude locking lever.

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