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Last updated: 31 August 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:	Advice Needed
Sent:	Friday, August 31, 2012 15:56:34
From:	Joe Oliveri (
I was needing some advice on my Meade ETX 125. Last night here in
Melbourne Australia we had a full moon and I did the usual alignment set
on easy. I noticed where it stopped there was no really bright starts,
only a very faint one. I pressed ok and it proceeded to the next star
and once again only found another very faint star. When I did a Goto
Moon it stated on the hand piece that the moon was not due to come out
until the early hours of the morning. I have just purchased this second
hand telescope recently and have followed all the instructions and
entered all my details as required also included my GPS co-ordinates
from google earth.
Any advice would be greatly appreciated
Mike here: Your message was originally DELETED UNREAD as SPAM due to the SPAM-like Subject line. PLEASE read the Email Etiquette page on the ETX Site Home Page to learn how to avoid this in the future. Thanks for understanding.
Just to confirm, have you done a CALIBRATE MOTOR and TRAIN DRIVES? Have you set the proper Time Zone and DST setting? When you centered the first star, was actually the named star? How far off was the star initially?

Subject:	[none]
Sent:	Thursday, August 30, 2012 08:37:57
From:	Horan, Patrick - Patrick (
I emailed you a couple times re problems w/brand new etx90 as You asked I keep you posted. After extensive trial and
error testing I've concluded that it's the high levels of humidity in my
area that are wreaking havoc with the electronics. It worked perfectly
inside my home on a simulated guided tour three times; twice for one
hour and once for 2.5 hours straight.

Between these 3 tests I used either batteries or a/c power. Both worked
well. After the 2.5 hour test, I turned it off, it sat for 2 hours
inside. Then I took it outside and set it up with  a/c power & turned it
on. The controller came on and immediately went black. Twice. Then I
tried different outlets and extension cords, after which it would turn
it on then immediately slew straight up or straight down. Not good. Then
I switched it back to batteries with the same results, slewing by itself
immediately after booting up.

A look at the atmospheric conditions at that time revealed a temp of 59,
dew point of 54, and a humidity level of 83%. I'm in Connecticut. I will
include all this info when I send it back (I've been given an RGA).

What, in your experience or opinion, do you think they can possibly due
to repair my scope? If it can't handle high humidity, what exactly do
you think they intend to do about that? Waterproof it? I don't think so.

If the scope can't handle my climate on any given night of the year, of
what use is this scope to me? I foresee an unbelievably hard-time
getting a refund after 30 days also. It's a tall order determining a
scope has this type of issue without having owned it longer than a
month, agreed?

Advice? Comments? Questions?

If possible, can you please reply to


Patrick Horan
Mike here: PLEASE see the Email Etiquette item on the ETX Site home page. Your message was deleted UNREAD as SPAM due to the blank subject line. Also, note the email address item. Thanks for understanding.
In my previous reply, I had a typo. The site should have been for AC adapters. Apologies for any confusion. As to high humidity, by itself that should not have caused electrical problems (although it can cause lousy seeing and dewing up of the optics). If moisture is getting on some exposed electrical wire or component, that could cause a short or change in electrical resistance. But I've never seen such a problem reported before. So, I would suspect that something is exposed that is normally not exposed.

Subject:	etx 90 ec focus issue
Sent:	Wednesday, August 29, 2012 14:44:23
From:	Bill Fullerton (
Trying to resolve poor focus on neighbour`s scope. My initial attempts
at startesting have left me unsure and reluctant at this stage to meddle
with the collimation.

The poor focus applies to both near and far objects. On checking I can
however focus sharply on an object say 20 ft away  viewing directly
through the back access (camera connection) and also with the eyepiece
removed I get the image good and sharp on the flip mirror. If I now
replace the eyepiece (super plossl 26mm) the image is well out of focus
and  vertical adjustment of eyepiece does not help. I assume that this
eyepiece and indeed any eyepiece inserted should focus on the flip
mirror image, is this correct or have I got lots to learn. The eyepiece
on its own looks ok and as viewed independently magnifies whatever is in
Hope I have provided enough information to determine a way forward, any
help will be much appreciated.
Best regards     Bill Fullerton (Lancaster UK)  
Mike here: When using an eyepiece in the normal (top) eyepiece position, does rotating the focus knob on the rear of the ETX change the focus at all?


From the state I described, on replacing the eyepiece there is no
recognisable image but it can readily be brought in to reasonable focus with
the focus knob, but it is certainly not sharp. A regular pair of binoculars
provides a much better result. A further observation  with "best available
focus" I found that by slight side movement of my eye over the eyepiece
seemed to momentarily bring the edge of the image into better focus.
Hope this helps.       Bill Fullerton 
Mike here: Try a test tonight on the moon. Can you achieve a good focus on it using the standard supplied 26mm eyepiece?


Very clear sky tonight and very bright moon nearly fills eyepiece. I can
make out large dark areas either side of centre but focus is much poorer
compared to 16x50 binoculars. With binoculars I can see what looks like a
very large crater low and left of centre between and below the dark areas
and lighter lines radiating from this area. Back to etx and whilst the
circumference of the moon looks quite sharp the general surface is not as
clear as described above. However circumference from about 3 o`clock to 5
o`clock shows what looks like craters almost in profile right on the
circumference. This detail between 3 & 5 looks quite sharp but confined to a
very narrow annulus.     Bill Fullerton
Mike here: Since the moon is not quite full this night, you will see some shadowing along the terminator. Since the limb of the moon is sharp, I suspect the telescope is reaching focus OK. Due to the moon's brightness, see sharp details on the surface will be difficult. Using a "moon filter" (or even sunglasses) will help the viewing by reducing the brightness. Once you focus on the moon, slew to a bright star. It should be in focus as well without needing to change the focus knob. If you go out shortly after sunset, you can also view Saturn, low in the southwestern sky (near the star Spica). With the telescope focused on the moon, Saturn should be in focus as well. However, due to its low altitude in the sky, viewing Saturn will be hampered by atmospheric distortion and so may not appear as crisp as when it was higher in the sky.

Subject:	Re: My Letter to Congress on Light Pollution
Sent:	Tuesday, August 28, 2012 18:47:08
From:	jose rua (
Thanks for doing that!  We will do so also to our reps. Mr. & Mrs. Rua

Subject:	ETX 105 RA sticking
Sent:	Sunday, August 26, 2012 17:34:20
From:	Max Byerly (
I repaired my ETX 105, I had to repair and swap out the motor. After
putting everything back in place where it should be and putting in all
the screws, and closing it back up.

When I went out the next night, and when I turned it to left, it hit the
stop and I put the left arm over the control panel. I started it up and
proceeded to do the alignment and when I went to Arcturus it had to
rotate almost one full turn to get to Arcturus. The only problem is what
it could go that far over to the right when slweing around to around.
About 70 percent of the turn it just stopped. You can hear the motors
keep going but the scope doesn't move any further. The clutch was locked
and engaged. If you loosen and try to turn it to the right it gets
really stiff and hard to turn. If you force it, it will move but then it
will not go the whole way back to the left stop without it getting hard.
I checked inside to make sure nothing was binding or tight and nothing
was. Have you ever heard of this or seen this?

Thanks and clear skies,


Sent from my white iPad 2
Mike here: It could be that the mount is not quite "square" on the axis bolt and so does not freely rotate. Check the mounting. Also, use caution when rotating by hand (or motor). If there is an obstruction, you don't want to break something. If the obstruction is a wire, you could cut it by forcing the movement.

Subject:	AC problems, ETX90
Sent:	Saturday, August 25, 2012 23:26:35
From:	Patrick Horan (
I just finished typing up my letter to Meade in preparation for sending
it back for repair. I've had it a grand total of 6 weeks and the last
few sessions I've had resulted in the scope slewing all over the place
by itself! I don't know if it's strictly due to the AC power (#546
adaptor due to design change) or not but the initial 6 pack of batteries
I started off with came and went and it seemed fine.

Now that it's been erratic I've switched back to batteries but it's
doing the same thing. I was hoping it wouldn't because I would've
ditched the adaptor alltogether but now I have no choice but to send it
back . I wonder if AC  power damages the electronics? They did not offer
to pay shipping, so that will be at my expense. Nice eh?  
Mike here: When switching power sources (ie, internal batteries to external AC or DC, or the reverse), you need to select CALIBRATE MOTOR on the AutoStar. That "tunes" the AutoStar for the power output level. You should also do that when internal batteries are low and no replacement is readily available. Next, be certain you have done a TRAIN DRIVES (on both axes). Both of these steps will normally cure erratic movement. You didn't say you had done those steps, so doing them would be worth the effort vs returning the adapter.


I described the problem I was having to Meade, they asked me to send the
telescope back for repair, after 6 weeks and only about a 8 sessions.
Things go smoothly for about an hour, then the scope literally begins
slewing all on its own, left/up/left/up/left/up, or straight up, or
straight down, wherever, with no input from the controller. The 'motor
default' warning came up a couple times and everything. It did it's own
'calibrate' after that but then immediately started slewing on it's own
again without touching the controller. The first few times it happened
was with the AC adaptor, the last two were with new batteries. 
I was reading some input on your forum, it seems like AC adaptors
bring out the worst in these telescopes. Do you happen to know why
someone couldn't just use a 9V battery instead of 6 AA's? The connector
is the same. 
Also, do you know how someone could make their own dew shield?
Mike here: You need 12VDC and 1.5A for the ETX-90. So, a 9V battery will not work reliably. And yes, some AC adapters have problems. You might check out the ones from I use one of theirs on my LX200-ACF. As to dewshields, lots of DIY tips on the Helpful Information: Telescope Tech Tips page.


Even though I may be an unlucky owner, I still love my scope.  : ) it
has always been 'on point' otherwise. Very accurate and great optics.  
Thanks for the tips.
Clear skies

Subject:	Super charging the etx
Sent:	Thursday, August 23, 2012 20:30:01
From:	Glocke, Tony Michael (
I have an ETX that needs supercharging do you still do this service?
Let me know.
Tony Glocke
Mike here: Dr. Clay Sherrod is the one who does that. See the Supercharge Service web page for further information and his contact info.

Subject:	125 Ports
Sent:	Thursday, August 23, 2012 17:46:24
From: (
I've had an ETX125 for about 2 years but have never used the rear port
with a diagonal. I've always used the top built in eyepiece adapter.
Question: If I buy a diagonal for the rear eyepiece port will I get
better views? If so which one would you recommend.

Mike Amonett
Mike here: Using the rear port takes the flip mirror out of the light path. That results in a slight improvement. But if you then add a star diagonal you re-introduce another mirror into the light path. If course, the higher the quality of the diagonal the better. Alternatively you could use a visual back on the rear port with an eyepiece to provide a straight through view. As to recommendations, I've only used adapters from Shutan (Apogee) and they are no longer available.


I guess what I'm asking is ;
Would the use of a quality diagonal be an improvement over the internal
flip mirror?

Thank you
Mike here: Yes, but the cost may not be worth the improvement. It will depend on how you use the ETX and with what eyepieces (also part of the optical quality equation).


Thank you.

And this:

I'm sorry, one more question: 
I have a good assortment of the RECENT Meade 4000 eyepieces. Should I
invest in in a quality diagonal with these EP's?
Mike here: Are you finding the views through the top port unsatisfactory? If not, then you may or may not see a difference at the rear port. I use a visual back and wide-field adapter on the rear port of my ETX-90RA. That gives me two magnifications at the flip of the mirror. But other than that, I rarely use the rear port on the ETX telescopes.


No,  I'm satisfied with what I see, but I thought I might be wasting the
ability of what I have seen called "superb optics" of the 125 if the
rear port is preferable. 
Mike here: As I said earlier, eliminating the mirror from the optical path will provide the best view.

Subject:	Re: ETX Bracket for 8x25 Rt angle Finder
Sent:	Tuesday, August 21, 2012 14:28:33
From: (
I went back today to see if it would go. No go! The leftside snapped in
perfeclty but right NOT ???? I and going to send pics in my next e mail.

The guy who did the photos of the tube lide out . Is he available via e
mail so I can figure this out. Or what I am doing wrong? Anain your help
is apprecated!

Jim Franey
Mike here: Not certain who you mean about photos and email. But you can contact Dr. Clay Sherrod; he's the guy who does the Supercharge telescope service and is good with answering questions. Just don't send him any photos; he's on a slow Internet connection.

Subject:	ETX 90 base question
Sent:	Tuesday, August 14, 2012 21:26:22
From:	Epiplayer3 (
Just a quick question. I have a etx 70 with autostar I just bought a etx
90 on ebay can I mount the 90 on the 70 base so I can use the autostar
and how hard would this be.  Thank you
Jimmie Dunn
Mike here: See the article "Putting ETX-90 on ETX-70 forks" on the Helpful Information: Telescope Tech Tips page.

Subject:	Tripod for ETX 125
Sent:	Tuesday, August 14, 2012 11:24:24
From:	Mike Startkey (
I am looking for a tripod for my ETX 125, and have found that both Meade
and JMI no longer make a unit for these scopes.
Do you have any suggestions for a decent tripod that is currently
Hopefully under $200 or less.
Thanks in advance,
Mike Starkey
Mike here: Have you contacted any of the ETX dealers. Someone may still have a #884. I checked OPT and they don't, but others might have one. Try Telescope Warehouse (link on the Astronomy Links page). Or you could consider making one. There are several homemade ETX tripod articles on the Helpful Information: Telescope Tech Tips page.


Mike, thanks for the info, I did find a guy with a Celestron unit very
similar to the Meade 884, will be very easy to adapt. Photos attached.

Do you have any input on the JMI Megapod?? I have found one at the same
price as the above Celestron, although probably a lot more shipping cost.

Really appreciate your input, just discovered your website today, will
provide hours of reading.





Mike here: Yep, that's very similar to the ETX #884 tripod. Search the ETX Site for "Megapod"; there are many comments on it.

Subject:	ETX Bracket for 8x25 Rt angle Finder
Sent:	Sunday, August 12, 2012 14:28:44
From: (
I  just came upon your site. A couple of questions please? One I screw
up and dropped the eyepiece screw in to my ETX 125 eyepiece holder. It
is now the in scope back ???. I dont know what to do? Will it hurt
anything? (I feel bad)

Do you have any ideas on where I can get a bracket for my ETX 8x25
finder scope. I have the finder just no bracket?

Any help will be appreiated!!!!   Jim Franey
Mike here: Screw inside the tube IS a problem! It could jam the movement of the primary mirror and prevent focusing. It could also scratch the optical surfaces. You will definitely want to get it out. If you can see the screw by looking into the tube from the front, you could unscrew the corrector lens housing (mark its position first to ensure you get it back on correctly). Then tip the tube front end down to let the screw fall out. If you can't see the screw, it would be best to enter from the rear. See the article by Doc G on disassembly at the bottom of the Helpful Information: Telescope Tech Tips page. I also suggest reading my article "Disassembly Procedure" before disassembling anything. In either case, once you get things back together, do a collimation test and if necessary re-collimate (articles on the Telescope Tech Tips page.
As to a finderscope bracket, try Telescope Warehouse (link on the Astronomy Links page).


Hello again ! Its not in the front. I hear it in the back (I think)
below the flip mirror. At the bottom of the plactic flip mirror
housing.( I cannot find the artical by Doc G on taking the back off????)
. How hard is it to ghet off? Mike apreciate the info and help!!!!   Jim
Mike here: It is called "Doc G's ETX OTA Guidescope & Disassembly Photos" and is almost at the bottom of the Helpful Information: Telescope Tech Tips page on my ETX Site. As to difficulty, like anything, easy if you know what you are doing and not so easy if not. Just follow the instructions in the article and you'll be fine. (don't forget to follow the guidance in my Disassembly Procedure article)


I just realised that I also have to get the tube amenbly off the arms
(Looks like 2 screws on each side?) "Then" I can get the back off (3
screws ?)
Then I can get this stuped screw  out ! 
I checked out the Docs pics over and over but he only deals with the OTA
not the arms?    Thanks again Jim
Mike here: Remove the two screws each side on the tube adapters. Then carefully pry the adapters away from the tube. The tube will then slip out.


I did it ! All but  But the  tube adapters ? Tube stop just shy of the
screw holes? Is there a stop in the adapter? Or should it just click in?
Mike here: There are little plastic tabs on the adapters that click into place on the OTA. That's why you have to pry them away from the tube.


The tube goe up to where the tabs sould click in but something it
stopping them?The tube seems level. the screw holes are maybe 1/8 away??
What could be stopping the tube?  Is there a way hold the Tube?   BTW
Thanks for your time and effeort with this !!!   Jim
Mike here: Some twisting and pulling may be required to separate the tabs. They should eventually release.

And this:

Left tab ( stapped in ) but no go on right one ? This should be a peice
of cake, But it is not  :-)    Jim
Mike here: It will work. Keep at it. Use patience and care.


Spent an hour on it today. Still no go ? I have decided to pull the tube
out again to see if somehow I have missed somthing?    Jim
Mike here: Could be that something is not quite aligning right.

Subject:	EP repair
Sent:	Wednesday, August 8, 2012 18:27:42
From:	AstroBob (
have you any advice on how to dry out an EP that was left in the weather?

Meade 18 mm 4000

Sent from my iPad
Mike here: If you have any of those small bags of silica desiccant, place them inside a cloth bag (or sock) along with the eyepiece. Let it sit for a day or several days. Depending on how much moisture got inside the eyepiece (and where), this may (or may not) work.

Subject:	FYI ETX-125 REPAIR
Sent:	Wednesday, August 1, 2012 14:14:30
From:	john (
my etx-125at had a malfunction with the alt motor assembly, it would run
then give a grinding noise the stop.

I took apart the gearbox and found nothing wrong inside, so I cleaned
out the grease mess put it together enough to see if it was any better.
I left the tube off and used my finger to put some pressure on the arm
and it ground like a coffee grinder and stopped moving.

I could see the gearbox and the problem was with one of the gears inside
the little gearbox, so as a last resort not able to locate any new gears
from anywhere including Dr. Clay I took apart my perfectly working
etx-90 pe.

The gear boxes were different but when I took the etx-90 gearbox apart
the gears were a match!, So I switched out the gearing, And my etx-125
works like a dream again! , the etx-90 seems to work ok but I will have
to test it on a clear night. I am hoping that maybe the etx-90 gears
will locate on some areas not worn and it may work too. But I just
wanted to let you know the gearboxes in the etx telescopes are different
but the gears inside are the same. I hope this bit of info may help
someone else. Seeya john

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