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Last updated: 30 June 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.

Subject:	Help with wiring for ETX-90
Sent:	Thursday, June 30, 2011 05:07:44
From:	Yoh, Michael (
I emailed you a number of months ago when the hand controller stopped
working with my ETX-90.  I've tried everything else with no luck.

I'm finally getting around to opening up my ETX-90 to see why motor
stopped responding.  Do you have a wiring schematic for the ETX-90 you
could email me?  My electronics engineer who is helping me today said
that a schematic would help greatly.

Mike Yoh
Mike here: No schematics available. Howwver, several of the articles on the Helpful Information: Telescope Tech Tips page will show wiring photos.
Subject:	Early and later ETX fork
Sent:	Tuesday, June 28, 2011 09:35:51
From:	John Lovda (
Can you please tell me the link that includes a picture comparing the
earlier and later forks (with a metal core)?  I cannot find it or know
what search words to use.
Mike here: I am not aware of any comparison photos.


The picture that I saw showed the surface under the large side knob (on
the side with the gearing) on each of the two versions.  They did look
Mike here: Meade has made many changes in the ETX models since 1996.
Subject:	Meade archives
Sent:	Saturday, June 25, 2011 18:01:44
From:	Erik H (
I wanted to say THANKS A TON for your documents, software, archives, and
help you keep on your Meade archives.

I just upgraded my AS 495 to a 497 with resources that you made readily

I hope you have to wade through hip-deep piles of "THANKS A TON" emails
every day.
A very appreciative jackass,

Subject:	Azimuth Motor Problem Meade ETX 80AT-TC
Sent:	Tuesday, June 21, 2011 14:00:30
From:	Ryan Goodman (
About a year ago, I purchased a Meade ETX 80AT-TC (with the standard
AutoStar).  The telescope has served me very well over the years, but
recently, the Azimuth motor will either fail to engage or slip. If I
nudge the telescope, it will continue moving, but this significantly
decreases the accuracy of the Go To capabilities. Has anyone experienced
this problem before? I'd be willing to do some manual repair work, but I
would really like a protocol so I don't screw things up worse than their
current state. I called Meade, and the guy seemed pretty clueless. (I'm
sorry if someone already posted this question, but I couldn't find it.)

Mike here: First, you need to determine whether it is physical restriction causing the problem or a loose gear or something else. Have you done a CALIBRATE MOTOR and TRAIN DRIVES recently? If not, do those. If that doesn't solve the problem, unlock the azimuth axis and slowly rotate the telescope back and forth several times around by hand. Do you feel any restriction in the movement? (By the way, this can also cure some problems by redistributing the lubrication.) Lastly, with the axis unlocked, run the motor. Does it sound normal?


Thanks for your help!

I had already calibrated the motor and all, but it seems like rotating
the telescope back and forth on problem areas really did the trick! I
guess that indicated a lubrication problem.

Thanks, again.


Subject:	etx-125 spare parts
Sent:	Monday, June 20, 2011 06:04:26
From:	Konstantinos Tsintarakis (
Hello from Greece,
I bought an ETX 125 PE two years ago.
Yesterday I try to replace the batteries and I got one contact lead
broken, also some more leads will be in the same condition soon.
Are those batteries contacts leads available as spare parts? Were can I
find some (3-4)?
 Thanks in advance.
Konstantinos Tsintarakis 


Mike here: Try Telescope Warehouse, link on the Astronomy Links page.
Subject:	RE: ETX-125AT electrical power issue
Sent:	Saturday, June 18, 2011 14:27:51
From:	Alan Boniface (
Thanks so much for your prompt reply. I am somewhat shocked at the
adapter sensitivities of this scope. I will try Telescope Warehouse as
you suggest.

I'll keep you posted.

Thanks again.

Mike here: Some people have added devices to protect the circuitry. See the articles "Circuit Polarity Protection" and "ETX-90EC Wiring Protection" on the Helpful Information: Telescope Tech Tips page.


Thanks again Mike. I really appreciate your help and suggestions, not to
mention the quick responses.

I have emailed Bill Vorce at Telescope Warehouse and await his reply.


And this:

From:	richard seymour (
You asked:
> 2. Is it likely to be more than just the one circuit board that
>  has gone faulty, ie has anyone had a similar fault experience with an ETX?

You should ask the repair person whether and *traces* on the power panel
card have been burned.
If they have, then most likely one of the motor cards has a damaged
component, and the power panel damage was due to the power panel acting
as a "fuse" due to the excessive current.

But if it's only the switch that's damaged, you could simply bridge the
switch points with wire, and control the "on/off" by disconnecting the
power cord (or removing a AA battery from the base).

> 3.  Is the repairer right that I need a whole new circuit board or
> should he be able to effect a repair on the current board, ie is the
> repairer not doing his job properly?

The approximate schematic diagram for the power panel is the same as the
LX-90's, which is shown here:

Without knowing a *lot* more about what you asked the repairer to do
(did you allow him the leeway to cut the switch out of the circuit, as i
suggested above?) i cannot guess if he's doing his job "properly". 
Meade does *not* make it easy to remove the power panel
(i believe they melt the telescope base's body plastic to hold it in
place... so simple removal is *not* "simple".
You might give Don Whiteman at BinTel (Binocular And Telescope) in
Melbourne a call or email:    ... he may be able to
supply the parts needed.

good luck


Thanks so much for your insights and the link to the LX-90 schematics.
I'll pass them onto the repairer to see if he can work with the info.

I really appreciate your feedback.


Subject:	ETX-125AT electrical power issue
Sent:	Saturday, June 18, 2011 05:16:14
From:	Alan Boniface (
I have a 3-year-old ETX-125AT which has developed a fault that I am
struggling to get help with. I hope this forum can assist.

When I last used the ETX about 6 months ago it initially powered up via
the normal AC adaptor (12v 2.5A) but during alignment the scope tube
suddenly started going down and bottomed out on the horizontal base.
Before I was able to get the power switch turned off there was a slight
electrical burning smell and then no power at all and hasn't been ever
since. I guess that there has been a short inside the ETX.

The New Zealand Meade distributor is unable to assist me so on their
advice I took the ETX to a local electronics repair shop and he
confirmed that there is no power getting from the first circuit board,
ie the one that has the AC power running into it and the switch attached
is burned out as no power is being passed out of it to the rest of the
circuitry inside the ETX. The repairer has asked me to get a new board
and he will install it for me. I do recall from the conversation with
the NZ distributor that the ETX scopes have 3 fairly simple circuit
boards in them so I hope the feedback from my repairer can help isolate
the correct board.

As I don't know what part I should be asking for I was hoping someone in
this forum might know. I will need to try to source the right circuit
board from a dealer outside New Zealand so I'll most likely try in
California directly.
So I have three questions:
1.       Does anyone know what part number(s) I need to be asking for?
2.       Is it likely to be more than just the one circuit board that
has gone faulty, ie has anyone had a similar fault experience with an
3.       Is the repairer right that I need a whole new circuit board or
should he be able to effect a repair on the current board, ie is the
repairer not doing his job properly?
Any help or guidance would be gratefully received.
Thank you.
Alan Boniface
Auckland, New Zealand
Mike here: I suspect the AC Adapter was at fault. If it was an older Meade #541 AC Adapter, I posted a warning about that a few years ago on the Announcements: Warnings! page. As to getting a board replacement, try Telescope Warehouse (link on the Astronomy Links page).
Subject:	ETX-90 Polar alignment
Sent:	Tuesday, June 14, 2011 11:08:11
From:	Jake Putz (
I was reviewing your ETX comments page and took note of the alignment
for the polar home position.  Is this the recommended position for the
deluxe field tripod?  I have also seen the alignment with the aperature
pointed toward Polaris and the fork arms parallel to the OTA while
mounted on a tripod.  Which is the correct alignment?

Mike here: You didn't specify which model ETX-90 you have nor exactly which article you mean (there are many "comments" pages). However, you will find many polar alignment articles in the "Alignment Tips" section on the Helpful Information: AutoStar Info page.


The old model ETX-90EC,  the same one you reviewed and had problems
aligning properly until firmware rev 1.2.  This is also the article I am
refering to, in concert with the performace enhancement part 5 article.
Mike here: Polar alignment is done with the fork arms pointed at Polaris and the OTA rotated the same as with Alt/Az mounting.


Thank you for helpiong me clarify that.

Happy observing.

Mike here: Don't forget to see those articles I mentioned.
Subject:	Compliments on your great Astronomy Links page :)
Sent:	Tuesday, June 14, 2011 06:44:26
From:	Lucy Nelson (
I enjoy astronomy very much, & I am frequently looking online for new &
interesting information. I stumbled on your Astronomy Links page in one of my searches, &
thoroughly enjoyed it, so I really wanted to say great job, & thanks!

Secondly, & I hope this doesn't seem rude, but I also wanted to make a
suggestion for your page. I thought you might be interested in another
helpful astronomy resource that I found recently:
I think it has some great information, so I thought it might be a really
helpful/useful addition to your page above!

Thanks again, & take care,

Subject:	Your review of MX-1
Sent:	Saturday, June 11, 2011 03:19:11
From:	Miguel Calejo (
THANKS! That's one of the best technical reviews I read anywhere about
any product! And I've read a few.

Best Regards,
Miguel Calejo

Subject:	Re: Dec Locking Knob:: Fixed
Sent:	Thursday, June 9, 2011 13:15:09
From:	Betty L Myers (
Thank you Mike;  I got it done, and its working fine.  It tock me awhile
but when I went to the Hardware store and found the peaces I needed it
all fell together...   Thanks...    Betty

Subject:	question on harness
Sent:	Wednesday, June 8, 2011 19:10:06
From:	David Shina (
I've got a question on your 11/28 blog at:

You stated you got a shoulder strap harness for lugging your heavy
equipment.  I need to do the same thing.  I am an environmental chemist
and I have to lug equipment, etc all over the place and I've been
searching for a good rig.  One that collapses and folds compactly for
taking up little space in my luggage.   How did it work out?  I will
have to carry equipment weighing around 20 lbs in a container that is
shaped like a messenger bag.  What was the make and model number?

I've tried a rig that just had the shoulder straps, but this was too
painful after a while.  I want to try the waistbelt/shoulder harness
combo.  I think it will distribute the weight better.  Thanks for any
Mike here: I'm not certain which case you are referring to on that page. But see my report on my 1999 trip to Australia with the ETX-90:
Unfortunately, the dealer who provided the case is no longer in business. But maybe the photo will give you some ideas. The case worked great.

And later:

Now that I'm back from the observatory, I see which case you are referring to. That is the case I used on the trip to Australia.
Subject:	Re: eyepieces
Sent:	Wednesday, June 8, 2011 17:25:53
From: (
First of all thanks for your reply.
Could you please clarify; could I possibly be limited by my hardware, ETX-125?

Mike here: The ETX-125 has very high optical quality, so using a low quality eyepiece will hurt the views. So, yes, the Meade series 5000 eyepieces can provide excellent views. However, two things to keep in mind: the ETX uses 1.25" diameter eyepieces, and the ETX is not very happy with a lot of weight added. As long as you use the smaller eyepieces, weight should not be a problem.
Subject:	ETX 125 PE Red Dot Finder Problem
Sent:	Tuesday, June 7, 2011 12:09:37
From:	Language Quest (
I have had an ETX125 PE for a couple of years now. When the telescope
arrived, the only thing wrong was the mounting of the red dot finder.  I
couldn't adjust the red dot to come anywhere near high vertically to
align with the telescope. As a 'short time' solution, I pushed a small
piece of wedge shaped wood under the front of the U-shaped holder that
clamps onto the OTA  to elevate it slightly and that worked OK. But over
the years the finder housing became increasingly unstable. Just touching
the finder slightly would move it out of alignment.

A couple of days ago I decided to see if I could fix it. I removed the
horizontal and vertical adjustment screws and removed the cover from the
finder. There was a piece of plastic with a nut encased in the middle
that had come loose and broken off.  I bought some epoxy and glued the
piece onto the place where I believe that it should go (where the
vertical adjustment screw comes up from the bottom of the finder
holder). That piece is now firmly attached again.

In the process, I accidentally pulled the LED from the top of the finder
housing so that the LED and its wires are now free and elevated by the
stiff wires above the circuit board. I was about to put it back into the
top of the finder when I thought I should check to be sure that the LED
lit properly. Alas, it doesn't light. I have tried setting the finder
blink on/off, tried pushing the "0" key, etc.  But at no time does the
LED show any light.

Everything else seems to work OK. The scope adjusts with the "Level
North" technology. I am using an external battery source; the Autostar
seems to be working fine; the scope moves in Azimuth and Altitude
without any problems.  I can do a false align (indoors) and it seems to
align OK. The only thing is that the LED on the finder doesn't light.

I don't think I did any damage while disassembling the finder - apart
from accidentally pulling it from its housing. The connections to the
LED appear to be solid and also to the circuit board.

The top  housing is all plastic - so I don't think there is an
electrical connection that needs to be made (a ground for example). The
time and date appear OK on the Autostar - so I assume that the battery
is OK.  That is a question I have though - does the LNT battery power
the LED?

Any suggestions on what I may have done wrong? The red dot appeared
without fail before I "fixed" it!


Mike here: See the Helpful Information: Telescope Tech Tips page for LNT/Smartfinder troubleshooting information. I don't recall which article mightg have the LED info.
Subject:	Barlow lense
Sent:	Tuesday, June 7, 2011 07:36:30
From:	Lawrence Ward (
I have recently purchased an etx-70 which I intend to use primarily for
terrestrial use.  I am, however, slowly purchasing accessories to make
it a complete and total unit.  My questions are: 1. What is a "Barlow"
lense.  2. What are the limitations on using a "Barlow" with the etx-70.
3. What size do you suggest, I've even seen one that varies from a 2 to
a 3.
Thank you for your assistance
Lawrence A. Ward
Oakhurst, TX
Mike here: A Barlow Lens is an optical magnifier that extends the focal length of the telescope, which increases the magnification provided by eyepieces. Typically, they come in 2X, 3X, or zoomable ones up to 5X. See the Accessory Reviews: Eyepieces page for some reviews. Two things to keep in mind: the ETX needs a "shorty" style Barlow Lens (otherwise you may not be able to focus with all your eyepieces) and you don't want to exceed the theoretical maximum magnification for your telescope. If you don't know what that is or how to calculate magnification, see the "ETX FAQ" page.
Subject:	eyepieces
Sent:	Sunday, June 5, 2011 18:16:04
From: (
Is the difference between the Meade 4000 and 5000 series worth the price
I have an ETX125 and only use it for stargazzing.

Thank You.
Mike here: Yes, there is a significant difference but depending on your observational experience, the Series 5000 may or may not be overkill for you and your ETX.
Subject:	Question on Selling ETX telescope
Sent:	Saturday, June 4, 2011 20:06:18
From:	Ron Leadbeater (
Hello, found your site while doing a google search. I have a Meade ETX
Telescope Product id 3514-030-01. I am looking to sell and would like
your advice on where to sell and value. Its all in the original box and
in great shape. Looks hardly used. Appreciate your response.


Mike here: I'm in my observatory now. Can't easily look up the model number. Can you be more explicit? Does it have the AutoStar? As to where to sell, there is eBay, Astromart, and of course, I can list it on my ETX Site.
Later: I came in briefly from the observatory. It appears you have the original model ETX Astro circa 1996-99, now known as the ETX-90RA. Depending on what accessories you have, you might try for $150-200, or perhaps more.
Subject:	Dec Locking Nob
Sent:	Thursday, June 2, 2011 12:12:06
From:	Betty L Myers (
I am in trouble..  The Dec locking nob on my ETX 125pe has snapped off. 
The Nob and the setting circle are lose but together and there is a
metal spacer about 1/2"  around the screw that comes off and under that
there is a black hard like plastic that the screw is in. It has snapped
or broken from the arm.  I can not tell if the screw itself has snapped,
but in the arm you can see the rest of the black hard like plastic and
screw in it..   Is there two separate screws here, one from the nob and
one from the arm?  Or is this supposed to be one screw from the nob? 
What do I need to do to fix this?  Thank you very much for keeping up
this site.  I read it often and it has help me many times in the past.. 
Mike here: See the article "ETX-90EC DEC fix (Right Tube Adapter repair)" on the Helpful Information: Telescope Tech Tips page.


I am in trouble..  The Dec locking nob on my ETX 125pe has snapped off. 
The Nob and the setting circle are lose but together and there is a
metal spacer about 1/2"  around the screw that comes off and under that
there is a black hard like plastic that the screw is in. It has snapped
or broken from the arm.  I can not tell if the screw itself has snapped,
but in the arm you can see the rest of the black hard like plastic and
screw in it..   Is there two separate screws here, one from the nob and
one from the arm?  Or is this supposed to be one screw from the nob? 
What do I need to do to fix this?  Thank you very much for keeping up
this site.  I read it often and it has help me on many occasion .
Mike here: I take it you did not see my previous reply, so I will resend it.
Subject:	Meade DSI II Autostar cable.
Sent:	Thursday, June 2, 2011 04:45:42
From:	martin gauckwin (
I have recently purchased a Meade DSI II cam for my MEADE ETX 125 scope.

I can get the camera working fine but when I try to connect the Autotar
handset to my PC for autoguidance I dont have a socket for it? please

Mike here: I assume you mean your computer does not have a RS-232 port. If your computer has only USB, then you will need a USB-serial adapter. Meade has one for Windows. But I recommend Keyspan for Macs and Windows.


much appreciated

Subject:	Re: ETX 125PE "Dead"
Sent:	Wednesday, June 1, 2011 09:39:33
From: (
Ok, so progress so far.  During closer inspection, it came to my notice
that some of the wires on the connector on the circuit board, the one
that connects the front HBX and Aux ports, were decidedly poor
connections, so I remade the connector.  The result was no different in
so much as the scope was still dead with the LNT connected.  However,
with the LNT disconnected, the autostar fired up and the RA motor was
now operative and responding to commands.  The DEC motor is still non

The conclusion I have come to is that there may well be a break in a
power wire that connects the DEC motor and perhaps the LNT.  To get at
this I need to remover the OTA but I am not clear how to go about dong
this.  There are some posts on your web site that indicate that you
simply use brute force to spread the forks apart - can this be true?
Many thanks
Mike here: There are four screws (two each side) that hold the OTA to the tube adapters connected to the fork arms. Once you remove those screws you still do have to gentle pry the fork arms away from the OTA.

And an update:

I now have a working ETX!!  The OTA slid out pretty easily in the end. 
The problem is certainly with the LNT cable it is truely a dreadfull
design, it is very tight and gets pulled about by the tube movement. 
Although I can't be sure exactly where the problem lay, the fault
disappeared when I introduced some slack and push home the connectors on
the DEC motor circuit board.  I stabilised the LNT cable with some glue
so it does not move around.
If it fails again I will re-route the cable, probably externally.
Many thanks for your expert help.


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