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Last updated: 30 November 2011

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.

Sent:	Tuesday, November 29, 2011 01:41:04
From:	Farhod Azarbaydjani (
I have an autostar ETX-60.  When I turn the power on the autostar
computer lights up for about a second and a half and abruptly shuts off.
 Any suggestions?
Mike here: First, PLEASE read the Electronic Mail Etiquette and Submittal Guidelines on the ETX Site Home Page. Your message was originally DELETED UNREAD as SPAM due to the ambiguous subject line. The Email Etiquette has suggestions on how to avoid that in the future. Thanks for understanding.
As to the problem, have you checked the obvious things like the batteries, cable connection, HBX jack? Look for bent or dirty pins on the connector and jack. Is this display just off? That is, can you still control the ETX from the AutoStar with the slew arrow keys?

Subject:	Using the photo port for a herschel wedge
Sent:	Sunday, November 27, 2011 14:52:07
From:	Bellinda Mall (
How do I use the rear port for a herschel wedge, and what adapters might
I need? Thanks, Bob
Mike here: Depending on the wedge design, you will need either a SCT-ETX adapter, ETX visual back, or ETX-specific accessory adapter.


The Lunt 1.25 wedge fits in any standard scope that uses 1.25 eyepieces;
so whatever adapter that would allow me to focus a 1.5 eyepiece would be
what I want. Thanks, Bob
Mike here: You can use either the top eyepiece hole or you can use the rear port with an ETX visual back. You can see an example (now discontinued) here:
Keep in mind that you will need a full aperture solar filter when viewing the sun with an ETX.


I found a visual back, but they warned that it might focus when used
with a 70 because of limited "back focus". The wedge I plan to use is a
diagonal and I think that increases the back focus. Do you think I will
be able to focus?
Mike here: Yes, there could be a focus issue. Whether that will be a problem will depend on the optical path and eyepiece used. If your plan is to do solar observing, a full-aperture solar filter for the ETX will be a better solution.


I've been using a full lens filter for years and everyone on my solar
observation web sight says a herschel beats them hands down.
Mike here: Only if it works! And you still need a full-aperture solar filter. Otherwise you can seriously damage an ETX.


The reason you use a herschel wedge is they transmit full spectrum light
unlike filters. The lunt has a fully intregrate heat trap and that is no
longer a danger. Any reefractor can use one, not so reflectors.
Mike here: There is a lot of plastic and glue in the ETX models, including the refractors. If you decide to try yours without a full aperture solar filter, let me know how it goes.

Subject:	Re:ETX 105 PE version problem - F/B 11/26/11
Sent:	Sunday, November 27, 2011 08:23:51
From: (
Did you change the internal battery of the LNT? That's the battery that
powers the LNT clock and when it dies, the Autostar doesn't see the
clock and assumes no LNT.
"I have been told to change the internal battery ..."
Mike Hogan

Subject:	re: Etx setting stops or limits
Sent:	Saturday, November 26, 2011 21:04:29
From:	richard seymour (
Just remember that the Setup/Telescope/Max Elevation
only affects *GoTo* operations...
it won't stop you from manually hitting the stops by leaning on the slew keys.

have fun


From:	john (
Thank you for the help! Happy holidays, john yezek 

Subject:	Etx setting stops or limits
Sent:	Friday, November 25, 2011 06:27:26
From:	john (
Hello mike, Happy Holidays!, John Yezek here, I have a etx 125, and a
few times now I have had the alt go close to 90 degrees and catch a
cord, or the electric focuser get jammed. Almost every time I panic then
hear the dreaded gear grind. I would ask you If you know how to set the
altitude stop so it will go to say 80 degrees alt and stop, In this way
I wont have to worry about anything hitting or getting caught and
ruining my gears,  thank you,,, John Yezek
MIke here: First, if you mean that the telescope slews to 90 degrees on its own, check the batteries. Also, do a CALIBRATE MOTOR; that will usually cure that problem. If not, do a RESET, CALIBRATE MOTOR, and TRAIN DRIVES. If you mean that you are slewing to objects and are concerned about the maximum altitude, you can set that a limit in the AutoStar. Use Setup: Telescope: Max Elevation.

Subject:	Quick question about a camera adapter
Sent:	Thursday, November 24, 2011 16:32:10
From:	zoran perovanovich (
Just wondering if you know what this adapter is called & what it does?


Mike here: Looks like a mirror that attaches to a SLR and then something else screws on. Beyond that, hard to determine. Almost looks like a prototype Lensbaby design (


Thanks Mike - Happy T-Day!

Sent:	Thursday, November 24, 2011 02:51:40
From:	frisky901 (
I am a first time buyer with telescopes and Meade had a MEADE
STARNAVIGATOR 102 WITH AUDIOSTAR and I am trying to find out some
reviews and information about from someone evaluates telescopes.
I can but one new and a refurbished one for little more than half price.
I was also looking at the ETX80AT TC confused about the AT TC series and
the BB series
Can you give any advise which might be better for a first time buyer
with telescopes.
Any thing would help.
Mike here: I have no experience with the Starnavigator model. You can check out the current (that is, new) ETX specifications page on the Meade web site ( You'll see that the ETX-80 Backpack (BB) model has a lightweight tripod, which may or may not be suitable for you. The non-BB model has the field tripod. The StarNavigator 102 does have a larger aperture than the ETX-80. Fainter objects will normally appear brighter in a larger aperture telescope, all other factors being equal. But since I don't have any experience with the StarNavigator, I can't confirm that is true.

Subject:	ETX 105 PE version problem
Sent:	Wednesday, November 23, 2011 05:16:45
I have a ETX 105 PE that keeps on thinking it is one of the earlier
versions (i.e. verion 43)  and will not go into automatic alignment.

I have been told to change the internal battery but this only seems to
work for a very short period,so I took the scope back to the dealer who
changed the handset and that seemed to work for a while, but now it's up
to the same old tricks.

Hopefully you or an associate may have come across this problem before
and will have some idea of how to resolve the problem.


Richard Webster
Mike here: Are you trying to update the AutoStar to something newer than 4.3Eg? If so, don't. 4.3Eg is the best version for the older AutoStar #497.


Thanks for your response. No I am not trying to update the version, the
problem is that the Autostar 497 will not go into automatic alignment as
it should on the 105 PE version. But keeps asking to be put into alt/az
alignment as you would on previous versions.

Hope my query is now clearer.
Mike here: Ah ha! It sounds like the AutoStar is not seeing the LNT. You can check for that by using the MODE display and seeing if the Finder options are shown. If not, then the AutoStar thinks there is no LNT connected. There are some LNT troubleshooting tips on the Helpful Information: Telescope Tech Tips page.


I shall look for advice on the Telescope Tech Tips page, in the meantime
the scope has decided to go into automatic mode, obviously has a mind of
its own.

Many thanks

Richard Webster
Mike here: Sounds like a loose connection somewhere.


It's a puzzler.



Subject:	Fw: Other: intrepid71a57 sent a message about 
Meade deluxe economy 90 1.25" telescope star diagonal #230614965712
Sent: Sunday, November 20, 2011 22:31:19 From: STEVEN C. FOSTER ( Hi Mike! Thanks again for all your help. Do you know if this would fit the etx 80 and work like the #933? Sent from my Verizon Wireless BlackBerry -----Original Message----- From: "eBay Member: scopehed1" Date: Mon, 21 Nov 2011 02:45:03 To: Subject: Re: Other: intrepid71a57 sent a message about Meade deluxe economy 90 1.25" telescope star diagonal #230614965712 Dear intrepid71a57, yes. it fits. i am not sure if the 80 needs the special 933 diagonal though to focus. you might check your owners manual. - scopehed1 From: intrepid71a57 To: scopehed1 Subject: Other: intrepid71a57 sent a message about Meade deluxe economy 90 1.25" telescope star diagonal #230614965712 Sent Date: Nov-20-11 15:36:29 PST Dear scopehed1, will it fit a etx 80? - intrepid71a57
Mike here: I couldn't determine what product you are interested in. The embedded links in your original email didn't show it to me. But the ETX-80 may require the special one since it is slightly different from the ETX-70 in that it has the built-in 2X Barlow Lens.

Subject:	Re: Removing the epoxy glue on the primary mirror on the ETX 125TB OTA
Sent:	Sunday, November 20, 2011 09:06:55
From:	Rich (
I have been lurking and exploring your outstanding site for the better
of a year. I first want to thank you for your work.

After a bit of hunting and patience I finally got a used ETX-125 mount
an Autostar  #497 off e-bay last few weeks to guide my old ETX-125 TB
from the Terabeam days. Now doing a 505 cable adaptor for computer
also with the info on this site.

From the picture you can see how I machined a camera adaptor tube for
Scope/camera both work well in this arrangement. 


Several postings on the site mentioned using an adjustable focus for the
ocular and getting the back end from a broken ETX125 for the flip mirror
couple that with a focus adjuster, since the primary mirror is epoxied
place on these units. Unfortunately the camera is a bit heavy and for
stability reasons I would like to be able to track camera focus using
original ETX system.

A few postings here
"  " mentioned
removing the glue on the primary mirror, assuming the original focusing
mechanism is still in place and functional. However, no one I could find
here or on the Web discussed how they actually did it. The three holes
the glue was injected are accessible from the outside and there is
sufficient spacing between the tube and the mirror edge to saw off or
the glue away. I could dremel away from the holes and saw off the excess
after removing the front plate and optics. I do not want to risk
the back since the primary is glued to the tube and might come with the
whole rear focus assembly. The grinding and sawing would create quite a
inside the tube of course. 

I am willing to risk having to re-collimate after the surgery and

Has anyone tried this or has a suggestion before I go in there!

Cheers and thanks.


Subject:	Meade's 5000 Series HD-60 Eyepieces on an ETX 125 PE
Sent:	Saturday, November 19, 2011 18:02:40
From:	Jerry (
I had a ETX 90 before and sold it to get the ETX 125 PE.  I consider
myself as a beginner star gazer.  I think that everyone is always trying
to improve what they have to view the skies.  Well I thought I would
upgrade my eyepieces by purchasing a Meade's 5000 Series HD-60 Eyepiece
to see how big of an improvement it makes.  Through ignorance I most
likely purchased too much eyepiece for that small telescope.  Well, to
my dismay I found that the HD-60 eyepiece will not seat completely down
on my ETX 125.  I have used your web site to find solutions to other
questions and problems throughout the years but this is the first time
asking a question.  I even pondered grinding about an 1/8" from the ETX
to allow the eyepiece the clearance it needs but I don't know how thick
it is at that location of the ETX 125.  Even if the eyepiece can't work
on the ETX 125, I hope in the future if the economy gets better I might
be able to purchase a larger telescope that this eyepiece can function
with.  Is there something I can do to make it work on the ETX 125?
Jerry from Florida
Mike here: Hadn't heard that there was a problem with the Series 5000 eyepieces. Even though it doesn't fully insert, can you still focus?

Subject:	adapter
Sent:	Saturday, November 19, 2011 08:25:32
From:	Brian Digiovine (
I'm looking to put a 1.25 diagonal on the rear cell of the ETX-125. Can
you tell me which adapters I will need to accomplish this?
sincere thanks,
Brian DiGiovine
Mike here: You need a "visual back" designed for the ETX. Apogee used to have one but it has been discontinued. But I believe there are still some ETX visual backs available online. To give you an idea of what this is, see the Shutan Visual Back comments I posted in 1998.


Thank you very much!

Subject:	what is better? Meade ETX-80AT-TC or Meade ETX-80BB to start off
Sent:	Tuesday, November 15, 2011 15:05:25
From:	Ramon Pastor (
Hello, I want to buy my wife a telescope but not sure what model I want
to get I like both of these but want to know the difference between them
and was wondering if you can help with that I am leaning more to the
Meade ETX-80BB.
Mike here: Check out the current (that is, new) ETX specifications page on the Meade web site ( You'll see that the Backpack (BB) model has a lightweight tripod, which may or may not be suitable for you. The non-BB model has the field tripod.

Subject:	re: mounting bolts
Sent:	Tuesday, November 15, 2011 09:53:02
From:	richard seymour (
(preamble: the scope has 1/4x20 holes in its base.  I'd recommend going
to a hardware store and getting *nylon* "quarter twenty" hex-head (or
wing-nut-headed) bolts "of adequate length" (the distance needed to pass
through the tripod head, plus another 5/8th inch).  The nylon will
prevent damage to the threaded inserts in the telescope base)

Why i'm writing:
Mike wrote: "the AutoStar #494 is not user upgradable."

Which is precisely correct, *but*...
the User Object (Comet, Asteroid, Satellites, Tours) data *is* "updatable".

So you can't change the operating firmware, but you can give the 494
newer orbiting body information.
You can also enter new, or edit old, objects on the 494 itself, but
eventually you will fill the 31KB of memory that the 494 uses for such
(available free space can be seen under the menu item Setup/Statistics )
Deleting an object via the keypad will *not* free up any of that space,
due to the physical limitations of the hardware involved.
The only way to "garbage collect", or compact, or shrink, the amount of
memory in use is via Meade's AutostarUpdate Utility (ASU) in connection
with a Meade 506 rs232 conversion cable (which contains an active
electronic lump mid-stream).

have fun


Thanks, so much. Bought the scope monday when it was raining so I know
things will work out LOL, clear sky's all- Steven- NH

Subject:	mounting bolts
Sent:	Monday, November 14, 2011 15:50:37
From:	Steven Foster (
Where can I get the bolts to mount my etx-80 at-tc to the tripod. I lost
them somewhere?
Mike here: First, try Meade Customer Support. They may send you some replacements (possibly free). Alternatively, see the article "#884 Tripod Replacement Bolts" on the Helpful Information: Telescope Tech Tips page.


Thanks Mike, having a problem getting into bag(see picture) and tripod
seems different, has a wing nut accessory tray don't know where the dew
shield is. Little confused here but scope works great and only paid $90.
The owners manual was still in plastic. Is the 494 upgradable? Think
this one says 2005 when I turn on. Sorry for all the
questions-Steven-Nashua, NH
Sent from my Verizon Wireless BlackBerry


Mike here: Try turning the focus knob to retract the objective lens housing further down the tube. That may shorten the length to allow the telescope to fit the bag. And no, the AutoStar #494 is not user upgradable.

Subject:	Deforking ETX 60
Sent:	Sunday, November 13, 2011 14:42:21
From:	Max Byerly (
I have a tabletop mount that I love so much that I want to put my ETX 60
on it. How do,you de-fork these 60s. I couldn't find anything on your
site. I know the 90s and 125s are easy, but I cannot figure out how to
do it.



Sent from my white iPad 2
Mike here: See the article "ETX-70AT Repair Guide" on the Helpful Information: Telescope Tech Tips page.

Subject:	Re: ETX105 problem with azimuth slewing
Sent:	Wednesday, November 9, 2011 12:26:36
From:	Tina Paramore (
Thanks for your reply. Having tried new batteries and done the calibrate
motors, the problem still persists. The scope will slew up and then
start turning and just carries on over the 360 degree mark turning full
circle without locating the star.

I checked the cables and jacks and all seems well to me. Tried
lubrication and even completely discharged and recharged the power tank
and went through the whole process again, still the problem persists.

Any more thoughts appreciated, otherwise it will be back to Green Witch
next week, hoping they can help...

Thanks, Tina

Sent from my iPad
Mike here: It is possible that a corrupted AutoStar ROM could cause the problem. You can try reloading the software. I suggest using version 4.3Eg.

Subject:	Love your website..
Sent:	Tuesday, November 8, 2011 19:44:57
From:	Daniel Towslee (
Ran across your website looking for information on the Meade ETX.  I
have had an ETX for years and love it.  Recently I began using it again
and became interested in having a live video camera attached to the
telescope so my daughter could see what I am looking at..  My dad is an
electrical engineer and has a full machine shop and said he would make
me a video camera from a high quality image processor and an adapter so
I can use it in place of the stock camera adapter for the ETX.  Problem
is that I do not have the focal length from the rear mount, focal plane,
image size, focus range, etc.. data my dad is asking for to make the
camera.  Are you aware of any resource for this kind of data?

Mike here: You can easily determine the values for your telescope. Remove the rear port cover and point the telescope at a bright day time distant scene (but not at the sun). Hold a pice of tracing paper at the rear port where you want the camera focal plane. Adjust the telescope focus and the distance of the paper until you get the scene in focus. Then measure the distance from the rear of the ETX to the paper. Also, measure the diameter of the circle of light on the paper.


Thanks for the info.. I will do the measurement first thing tomorrow. I
know if I can get my father very accurate data he will build me a great
camera; his hobby is amateur television  and he has built many cameras
but is unfamiliar with astronomy... Your comments are very helpful in
helping me relay the details to him.  I will post what we come up with
to your website..

Thanks again,

Sent from my iPhone

Subject:	Power cord question
Sent:	Monday, November 7, 2011 11:23:04
From:	Chad Jewell (
A month or so I was looking around the site and had read (and unable to
relocate the post) that the center post to the ETX-125's are positive. 
Thinking that I could manufacture one of these seemed pretty logical to
a point but I found a cord for my kids portable DVD player for the car
accessory plug-ins.  Not being mechanically inclined my any means I
attached a diagram of  the label from the side of the player below (and
attached in case it didn't come forward), I assume that it is showing
that the center pin is positive.  My second question would be that the
diagram shows it as 9.5V. To the best of your knowledge would that work
with the telescope?  It I would try it what damage would/could it cause?

Chad Jewell


Mike here: You likely read it on the ETX FAQ page. As to voltage, you will want closer to 12VDC, with 1500mA.

Subject:	ETX105 problem with azimuth slewing
Sent:	Sunday, November 6, 2011 14:42:53
From:	Tina Paramore (
When trying to easy align the telescope using the autostar in the alt/az
mode, the scope will first slew vertically and stop and then begin
slewing horizontally, but continues to turn without seemingly being able
to find the star it is searching for. On occassion it will continue
slewing until it reaches the hardstop. On a few occassions the handset
then displayed the message motor drive fault.
I have tried a reset, but this did not make any difference.

Everything appears to work fine, but the scope appears to be unable to
find the star. Any advice would be greatly appreciated.

Thanks a lot, Tinar

Sent from my iPad
Mike here: Have you done a CALIBRATE MOTOR and then TRAIN DRIVES? If not, do those. Also, replacing with fresh batteries can help. Do the CALIBRATE MOTOR anytime batteries are changed.


Thanks for the prompt reply. I am using a fully charged powerpack, I
have calibrated and trained the drives and performed a reset, and
trained and calibrated again. Problem still the same, does not seem able
to find the star. 
Any further thoughts would be welcome. 
Mike here: I would suggest trying internal batteries to rule out the external power source as the problem. Remember to do a CALIBRATE MOTOR when switching power sources. If that doesn't solve it, the next thing to check would be the HBX cord and jacks; look for dirty or bent pins, or pins that are depressed too much. If all's well with the cord and jacks, try redistributing the lubrication. Unlock both axis locks and slowly move the OTA by hand, hard stop to hard stop, back and forth, up and down, several times. If that doesn't cure the problem, the next thing to check would be the encoders; perhaps they are dirty. But you'll have to open up the base and fork arm to check that.

Subject:	Clearance on DEC movement ETX 125PE
Sent:	Wednesday, November 2, 2011 12:14:32
From:	Wim Lammerschaag (
I noticed some clearance on my Dec movement, it is possible with a
clutched drive to move the tube a few milimeter.
I dont know if its normal or a sign of something wrong in the drive?
You have any idea what the normal tolerance is?
Hope you can help me out!

Best regards from a clear skies Netherlands!

Wim Lammerschaag
Mike here: Not certain what you mean by "clearance". But if you mean that the OTA moves when you push on the tube, some movement is normal. But normally you don't push on the tube.


Thanks for the quick responce
Sorry, clearance could be ships language (i work on a ship as electrical engineer).
Yep i ment the movement when you push the tube up with a clutched drive.
Having some problems with the accuracy of the alignment so busy ruling
things out and bumped into this.
So if its normal, i can look futher.
Thanks for the answer, one thing less to worry.

Mike here: If having alignment problems, see the Alignment Tips on the Helpful Information: AutoStar Info page.


busy with now, thank, thanks !!

And more:

Slowly making progress.
All objects after alignment are more a less in the middle of the smartfinder visor..
Now the eyepiece.
Nice on the site are very helpfull
regards Wim

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