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Last updated: 31 March 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:	Should the azimuth lever be locked when at home position for autostar alignment?
Sent:	Monday, March 28, 2011 17:37:52
From:	Stephen Daiboch (
Once you have rotated the ETX OTA clockwise to North for home position,
should you relock the azimuth lever, before executing autostar
Mike here: If you don't lock the axes (both), the motors will run but the telescope won't move to the alignment stars. Once the alignment is completed, you should not normally unlock either axis to manually move the telescopes; always use the slew arrow keys or the GOTO functions.
Subject:	Meade ETX 90ra threaded lens cap is stuck tight
Sent:	Sunday, March 27, 2011 21:46:23
From:	Michael Rollo (
I have been trying for the last 5 days to remove this cap.

I first started with rubber good

then I used a rubber mallet and taped the the sides near the cap and the
cap itself to see if I could possibly loosen whatever is holding it in
place like this.

I still cant budge idea how long this cap has been like this,
since I bought this used... $20.00..looks great..but!!!

I had thought maybe using an adhesive on the lid with possibly a large
bolt then I'd have something to grip, this cap is so thin.

I am at my wits end here with this. Can't think of anything else I can
do to get this cap off.

Hope you have a suggestion, the only thing the techs at meade said was
to use a rubber mallet, which I already said I tried.

Hope you have a better suggestion than they did.

If not, thanks anyway.


Mike here: Try the tips in the "Q. I can not remove the aperture or rear port cover or loosen the Declination/Altitude scale knob. How do I loosen it?" on the ETX FAQ page.


I had already tried all those suggestions I found on your amazing site.

Unfortunately, they didn't work for me.

I had seen someone mention they were successful with a strap wrench, but
I don't see how a strap wrench would work on a cap so thin and snug to
the ota

I tried with a home made strap wrench, and it just wouldn't stay put.


looking for a miracle

There has got to be a way..I mean, without destroying the ota I mean :)

Thank you for the quick response


Mike here: Try alternating cold and hot then. Try to not get the objective lens housing cold or hot, just the lens cover. A challenge, yes. But something should loosen it. If all all fails, mark the position of the lens housing on the OTA and then remove the housing. Maybe that will allow for a better grip on things.

And more:

I have already messed things up.

I took the lens housing off without thinking to mark wondering
how much I have messed things up for myself even if I get the cap off.

guess I've really done it this time.

I had thought I'd damage the mechanics if I started banging away with
the rubber mallet.

I'm going to do as you suggested, hope it works.

Know anyone with a 90mm OTA for sale?

Thankyou very much for your help. I'll let you know how all comes out.


Mike here: You probably didn't mess things up (too badly, if at all) by removing the housing. Once you get the cover loosened and put the housing back on the OTA, just turn it until it is tight. Then do a "star test". You can find details on star testing and collimation on the Helpful Information: Telescope Tech Tips page.

And more:

Just wished to say thank you for the help.

I still havn't gotten the cap off, I tried for hours with the hot and
cold. Still wont budge.

Havn't decided what to try next, maybe gluing an over sized bolt on top,
and the using a wrench, pretty sure that wont work either, probably just
make a mess,

I have lost almost all optimism, kind of like locking ones self out of
their running car.

I am not a quiter though, and I'll keep you informed when and if I ever
get this cap off.

Thanks again, and hope all is good with you.


Mike here: Strange. Just to confirm, you are turning the cover in the correct direction? When looking directly at the cover (the cover is closest to you, housing away from you), the cover should rotate counterclockwise to be removed.


Yes, I'm turning it counter clock wise, It's like nothing I've come
across before.

I just don't get it, I have twisted so often and hard I split my thumb
in several spots.

I'm thinking maybe using a vise grip, the type used to hold wood
together while gluing, and see if I can get some purchase on the cover,

Then maybe using a strap wrench on the bottom ..If I can get the vise to
hold firm on the cap, it may just give me enough leverage to get it to
turn, from what I see in pictures, the threads don't seem to go very

I have both the  ETX 70 and 80, and both have plastic caps, I always
thought cheap. but it works.. I'd much prefer those in exchange
right now.

If you can think of anything else that may work. please. please let me

I'll keep you posted also.




Subject:	how do we get on your mailing list
Sent:	Saturday, March 26, 2011 02:18:43
From:	jo3777 (
Please advise us as to how to get on your mailing list.  Thanks.
Mike here: See the "Site Update Notifications" section on the Site Guide on the ETX Site home page.
Subject:	RE: ETX125PE Dec lock 'flop' problem.
Sent:	Thursday, March 24, 2011 12:28:29
From:	Brian (
I have been using the ETX with no problems and a much better clutch

However, I have been puzzling about what could possibly have cause the
damage to the original plastic stub axle.
The damage looked as if it was caused by something repeatedly moving the
tube upward against the top hard stop, thus moving the tanged lock stop
washer against the softer plastic axle. This definitely did not look as
though it was caused by mere pressure in an upward direction; more like
constant banging of the tube up against the stop.

I was sure that it was down to the way that I put the scope in the case
and took it out again. But I always handle the scope like eggs, so I
doubted it could be down to me.

I have been playing with the scope, putting it in and out of the case
and I am now convinced that the damage was caused by the construction of
the foam liner in the case. I use the Meade alumin(i)um case and put the
scope into the case with the top of the tube uppermost as demanded by
the LNT unit being on top. I always leave the clutch/lock unlocked and
this may be exacerbating the problem.

I discovered that when the scope is resting on the foam base of the
case, the weight of the scope base and fork arms pushes the pivot points
downward into the foam and the foam under the front of the tube pushes
it upward. This means that all the time the scope is in the case, and
this includes being shipped across Europe on holiday and out to dark sky
sites in my car, the foam is banging the tube upward into the lock stop.
All of this force is transferred via the lock stop washer into the
plastic stub axle, thus causing the damage shown in the photos.

I have now sculpted the foam from the front of the scope area and added
more under the pivot points to obviate the problem, so that the scope is
now lying in the case with the tube at an angle of about ten degrees
away from the lock stop, rather than banging against it.

Others who use this case might want to check that it isn't causing the
same damage to their scopes.

Regards, Brian

Subject:	ETX-90EC Update
Sent:	Thursday, March 24, 2011 12:23:54
From:	David Ritchey (
In one of your pages you describe a failure of the Right Tube Adapter
and how to fix it. At the close of the article it states:

"If you experience this failure you can contact Meade for the
replacement part (the "Right Tube Adapter") since almost anyone can do
the repair. There is no need to return your scope (with all the shipping
charges) to Meade."

I'm afraid to have to report that this is no longer true. I had an
ETX-90 donated here and it had a broken Right Tube Adapter. I called
Meade customer service and was told that part is no longer available and
that they would not be getting anymore in. For what ever reason they
have adapters for the left side (they even sent me one!) but you can't
get one for the right side. Meade insists I have to send the telescope
to them for repair.

This is horribly frustrating as I now have a nice $500 telescope
rendered virtually useless for want of a $7.00 piece of plastic.

If anyone knows how I might be able to locate a replacement Right Tube
Adapter, please let me know.

Thanks much,

David Ritchey
Associate Director
James S. McDonnell Planetarium
Saint Louis Science Center
Mike here: Yes, they stopped that policy several years ago. You must have seen an older page on the ETX Site. You might be able to do the repair yourself, see the article "ETX-90EC DEC fix (Right Tube Adapter repair" on the Helpful Information: Telescope Tech Tips page.


Wow - - - that's a quick response. Thanks!

Yes, I've seen that article and I'm actually saving that for a last
resort. Yesterday I talked with Bill Vorce at Telescope Warehouse who
said he might have some of these parts laying around. Fingers are

You have an excellent and very helpful site. I own a Celestron 6"
reflector and was not familiar with the ETX-90. What you have assembled
has been extremely helpful. Keep up the good work.

David Ritchey

Subject:	Focuser: ETX125PE - Focus 'falls' in and out when scope elevated on the declination axis
Sent:	Thursday, March 24, 2011 03:46:38
From:	John Wills (
I have recently bought an ex-demo ETX 125PE. I believe there is
something wrong with the focuser: At present, twisting the focus knob
does not focus the image - instead the focus knob and attached rod must
be pushed or pulled to achieve focus (very hard to fine focus with this
approach). When the telescope is elevated on its mount, the focus rod
falls in or out by gravity making it impossible to focus on distant
objects without holding the focuser in the correct place (which of
course makes it shake...) The grub screw in the knob is tight, and the
shaft rotates when the focus knob is turned, but at present this doesn't
adjust the focus. The rod must be pulled or pushed to achieve focus, and
then slides back on its own when the scope is elevated.

I was not keen to disassemble until checking this out further! Thanks
for the fantastic site - learnt so much from browsing it over the last

Best Wishes from the UK,

John Wills
Mike here: It sounds like the focus shaft has become disconnected from the main mirror. See the article "Focus Shaft Fix" on the Helpful Information: Telescope Tech Tips page.
Subject:	ETX-90 Broken right support arm follow up.
Sent:	Tuesday, March 22, 2011 18:44:27
From:	p f (
I'm not sure if you'll remember me, but I emailed you last month about a
broken ETX-90 right support arm.  I contacted Meade and they said they
don't supply the parts anymore and it would cost me $150 to repair.  I
decided that wasn't an option and that I would either try and buy a used
one for parts, or I would buy a CG-4 mount and just put the ETX ota on
that.  Well I ended up doing neither.  I took the fork arm apart and
managed to repair it so that the dec knob would lock again. 
Unfortunately, the scope won't move electronically in declination
anymore.  The motor runs but the tube stays put.  I'll have to take it
apart again and see if I can find out what the issue is.  But, at least
I can use the scope manually now.

Although I didn't make either of the purchases I was considering, I did
end up getting a pretty good deal on eBay.  While looking for a used
ETX, I came across an ad for a Celestron C6 refractor on a CG-5 mount. 
The seller was only offering local pickup, but as luck would have it he
was located about an hour away from me right here in New Jersey.  I got
the scope and mount for $400!  He even through in a box of accessories
at no extra cost.  The extras included a minus violet filter, a solar
filter, a cheshire collimator, a barlow and a couple of Celestron
plossls.  Not bad at all.  The scope, of course, is gigantic.  It's
pretty much the opposite of the compact little ETX.  I'd say the two
scopes complement each other well.

Now I'm looking for a mounting plate to see if I can mount the ETX on
the CG-5.  I'm fairly sure the mount can handle the ETX ota.  :-)  It
should be rock solid when I use my new Orion binoviewer with it.  The
binoviewer works quite well with the ETX.  There's no problem coming to
focus.  I've never had a German equatorial mount before, so I'm pretty
much in uncharted territory here.  Any suggestions on a mounting plate
that will work with the ETX on a CG-5 "vixen" style dovetail mount?
Mike here: There are many rings and dovetail adapters that will work. Check Losmandy and ScopeStuff (links on the Astronomy Links page).
Subject:	FW: Finderscope Sky Surfer III para el etx 80
Sent:	Tuesday, March 22, 2011 08:40:33
From:	miguel angel marin sala (
Te mando fotos de como he instalado el finderscope Sky Surfer III de
Baader Planetarium en mi ETX 80.
He pegado la montura del finderscope con cinta adhesiva dos caras al
telescopio y le he pasado un cincha de plastico para que est todo ms
Es un finderscope muy practico, no pesa nada, es muy comodo de utilizar
ya que se puede mirar con los dos ojos abiertos. Y va perfecto para el
ETX 80.



Mike here: Please read the Submittal Guidelines on the ETX Site. Thanks for understanding.
Subject:	Meade Electronic Focuser on ETX 105
Sent:	Saturday, March 19, 2011 15:15:02
From:	Anthony Moretti (
Just to start I would like to introduce myself. My name is Anthony
Moretti I am a Chief Petty Officer in the United States Navy and an
amateur astronomer. I must tell you that I really appreciate your site.

I had a few comments on the electronic focuser I recently purchased this
year in Jan 2011. First, my instructions did inform me to ensure the
telescope remained level during the installation procedure. I Use my
scope about 8 hours a week. I believe the installation was extremely
easy. I even had my 3 year old son help me install it. I agree there is
a little lag but the gain of the focusing time greatly out weighs the
scope shake. Also another great investment was the Meade anti-vibration
pads. the two of the accessories together had made the ease of viewing
and experience that much more exhilarating. The two products together
have been the two best accessories I have purchased yet with the
exception of my 4k series eye pieces. I have a new piece of equipment I
found that I was actually looking for a review on your site for. That is
how I came across the electronic focuser reviews. It is made by
AstroZap. The specs are listed below. I have ordered it and I will
inform you of how well it works.

ETX Eyepiece Tray
Fits ETX 90, 105 & 125
Holds seven 1-1/4-inch eyepieces, standard or Autostar hand controllers.
Built in Bulls Eye bubble level.

Thank You for your time!

Respectfully, ETC(SS) Anthony Moretti Pearl Harbor, HI




Subject:	A question about your site.
Sent:	Wednesday, March 16, 2011 16:16:25
From:	John Lovda (
Does your site have a message board where individuals can ask questions
and other members randomly reply if they know the answer?
Mike here: See the Site Guide on the ETX Site home page. Also, there is the ETXAstro Yahoo Group.
Subject:	884 Delux Tripod
Sent:	Tuesday, March 15, 2011 18:16:07
From:	Ron Harries (
I am looking for a telescope in the $800 area with a equatorial mount.
Will you give me your opinion of the Meade 884 tripod mount with an ETX
125 mounted and say a Meade 6" f/5 N-6AT LXD75. For AP do the German
Equatorial work better than the EXTs mounted on a 884 in the equatorial
mode. I am attracted to the ETX due to its longer focal length but if
the equatorial tracking is not that good I may have to go for the
shorter Meade or Celestron.

Ron Harries
Mike here: The telescopes you mention are totally different designs, not just in the mounts, but in the optical design as well. You need to decide which OTA meets your requirements and go with that. I had a LXD75 8"SC (until it was stolen); the mount is excellent. The #884 tripod is a little less sturdy than the LXD75 but is suitable for most purposes with the ETX-125, even in polar mode (except at very low latitudes). For astrophotography, either can work depending on the nature of the astrophotography and your equipment. For visual purposes, either mount will work fine.
Subject:	Flexible focuser for Meade ETX-90EC
Sent:	Sunday, March 13, 2011 19:08:03
From: (
First off, let me say I REALLY appreciate your Mighty ETX site!  Thanks.

A quick question.  In your opinion, where is the best place to purchase
one of those flexible focusers for the ETX90?

Jim Koerth
Rockport, Ma. 01960
Mike here: Actually, check out the Helpful Information: Telescope Tech Tips page for tips on how to easily make one.
Subject:	Storing etx125 in hard case
Sent:	Sunday, March 13, 2011 12:23:52
From: (
Love your website!  

My question -- is it OK to store my ETX 125 for several days or months
in the hard case that I bought for transporting the scope.  I don't have
the original box it came in.  I have been keeping it assembled on the
tripod in a closet in my temp controlled condo in Florida since June
2005 with no issues.  Since I just removed the batteries and don't know
when I will be able to take it out again, I don't want to put it back on
the tripod until I'm ready to use it again.  And I don't want to risk
knocking it over in the closet.

Should I just put it back on the tripod instead?

Thank You
Mike here: Keeping it in the case should be fine. Just be certain you unlock the axis locks.
Subject:	Keeping the batteries in my ETX-125EC
Sent:	Sunday, March 13, 2011 10:26:58
From:	Andrew Harris (
Yesterday I picked up a 12 Auto jumpstarter from WalMart, and the
correct cig lighter cable from Radio Shack, and now my question is,
should the AA's be left in the scope?

Instinct tells me that it is a bad practice to leave batteries in
anything for a long time, and risk leakage, any advice?


Back to Astronomy after 35 years! 
Meade ETX 125 EC Telescope 
Nikon D5000 
2010 MacBook Pro 
Ipad, I-everything 
Mike here: Generally, it is a bad idea to leave removable batteries in any device when they are not likely to be used for a long time. Leakage is always possible. That said, I'm quilty of leaving batteries in my ETX telescope for years and so far, no problems.


Thanks for your speedy reply!  I'm really happy with my Telescope, your
website is an absolute godsend for us ETX users!  Many thanks!

I live in Springfield, MO, and would love to come down some time and see
your Observatory.  1 question, how long does your suercharge service
generally take?  Cost??

Mike here: The "Supercharge" in not MY service, but is done by Dr. Clay Sherrod. The link on the ETX Site Home Page has all the details.


Righto!  Sorry, but thanks again for the great info!

Subject:	re: ETX 80 - Battery problem
Sent:	Saturday, March 12, 2011 21:35:29
From:	richard seymour (
Here's what i'd try:   load in the Kodak Zinc batteries.

Now replace them ONE AT A TIME with the Alkalines.
If/when it stops working, pull *that* Alkaline out, and put another
Alkaline in its place.
Eventually one of the Alkalines will be "left out", and *that* battery's
internal failure will be revealed.

I run my ETX 90 on Alkaline batteries, and have since i bought it in
(well, usually i run on an external mains adapter, but it always has
Alkaline (various brands) inside for portable trips.

good luck

Subject:	ETX 80 - Battery problem
Sent:	Thursday, March 10, 2011 04:53:48
From:	DEMOL Maarten (
Congratulations with your helpful website!
About a year ago I bought an ETX 80 telescope and it worked fine until
my first batch of batteries ran out.

I was using Kodak Extra Heavy Duty Zinc Chloride batteries, AA, 1,5V,
UM3 and they worked fine. Now I have been trying to find those UM3
batteries, but I haven't managed to do so.

I tried different other AA batteries, mostly Alkaline of the type LR6
and none of them seem to work.

According to the European Meade support branch ALL AA-type batteries
should work  L 
But when you look at the battery compartment it clearly says UM 3x6.
Funny enough the German guy claimed this isn't the case (that only
specific batteries work) that all AA batteries have to work and that is
it is a problem with the telescope.

My question to you would be if you can confirm this or if you have any
knowledge of what batteries should work and what AA batteries won't
work. And do you have any knowledge or experience concerning using
rechargeable AA batteries being sold everywhere nowadays?

I thank you very much for reading this email and my gratitude will be of
astronomical quantities if you could solve my problem.

Best regards, Maarten Demol

PS: I am also on the lookout for the power adapter, but that still
doesn't solve my battery-issue.
Mike here: You can find several articles on "batteries", including rechargeable batteries, on the Helpful Information: Telescope Tech Tips page. Any AA battery, at least, for awhile. You don't say what the problem is that you are having. When swapping in fresh batteries, have you done a CALIBRATE MOTOR? That solves many problems.


Thanks for your reply!

In fact my problem is that when replacing the "Kodak Extra Heavy Duty
Zinc Chloride batteries, AA, 1,5V, UM3" batteries with "normal" Alkaline
AA batteries the power doesn't even come on... when placing back the as
good as empty kodaks the power does come on.

the MEADE support guy said I could not use rechargeable AA's because
they could/would damage the ETX electronics... I read different things
on your website in relation to batteries... in that sense that I got

For instance one article by Michael Morris on your website, he claimed
to be using the rechargeables with success.
But I also read something from Michael Lang "I would advise against use
of NiCad's or NiMH batteries in the telescope internal 8-cell holders.
To do so will power the scope at much less than the desired 12 volts,
in fact, the scope will be powered at only 10.4 volts - best case. "

So basically I was wondering, if my ETX does not work with "any" regular
alkaline battery,  does this mean I need to send it in for repair?

Best regards, Maarten
Mike here: If the power on the ETX does not come in then I would suspect either bad batteries OR a bad connection in the battery compartment OR one or more batteries being inserted the wrong way. Rechargeable batteries SHOULD work but they may not last as long (or require a more frequent CALIBRATE MOTOR).



I have two sets of batteries, the old kodak's and brand new duracell's

When I place the old kodak's the ETX works, when I replace them with
the, different new kodaks (not the extra heavy duty ones) or brand new
duracells the etx doesn't work...
When I place back the old ones the etx works again...

Which made me assume there's nothing wrong with the batteries itself (2
different brands, new batteries,...)
Nor with the connection  between the compartment (as the ETX still works
with the old batteries, though they are as good as finished (empty))
And I am really really sure they are not inserted the wrong way...

So in fact the MEADE guy was telling my nonsense when saying
rechargeables would do damage to the electronics of the scope?

Thank you for replying!
Mike here: ANY battery can do damage to ANY electronic components IF there is a problem. Rechargeable batteries used to be prone to more problems than non-rechargeables. Sometime rechargeables will work fine and sometimes they won't. Different brands and different types of batteries can have different results on the same equipment. Your mileage may vary. Have you measured the power output from the batteries you have?
Subject:	Meade 07077 #1244 Electric Focuser
Sent:	Wednesday, March 9, 2011 13:44:57
From:	Biggs, Steffan (
I wanted to know if the Meade 07077 #1244 Electric Focuser can be
modified for the EXT 125?

Thank you, your website is invaluable for all EXT users.
Mike here: See the article "Meade #1244 Focuser Mod for ETX-125" on the Helpful Information: Telescope Tech Tips page.


Thank you!

Subject:	re: ETX70/80
Sent:	Tuesday, March 8, 2011 18:18:19
From:	richard seymour (
IF memory serves (from reading old articles), the OTAs are exactly the same...
except for the front lens and carrier (the ETX70 has a ring around the
lens to hold it in the 80mm holder).
If so, you may be able to simply remove the front lens assemblies
(including carrier) and swap them.

There's an article somewhere on Mike's site about someone adding a
larger lens on, too.

good luck
Mike here: I didn't remember that.

And an update:


My statements about them being interchangable was based upon the 60 and 70
(sixty and seventy), not the 70 and 80.
(but there is an old posting on Mike's site about someone putting an 80mm lens
(but not from Meade) on the front of an ETX70 (or 60).

my apologies for any confusion

Subject:	ETX70/80
Sent:	Sunday, March 6, 2011 22:59:35
From:	Steve (
I have a EXT 70 working great, have an opportunity to pick up an 80, but
motors don't work, is it possible to take the 70 out of the mount and
drop in the 80?
Mike here: I don't have an article on the ETX Site specifically about that but see the article "ETX-70 Disassembly Instructions" on the Helpful Information: Telescope Tech Tips page. It should help with removal of the OTA. As to whether the ETX-80 OTA will fit, it should BUT since the focal length is longer than the ETX-70, I'm not certain whether the OTA will clear the base when pointed towards the zenith.
Subject:	ETX 90 Motor Failure
Sent:	Sunday, March 6, 2011 05:51:45
From:	bren (
My ETX 90 motor drive has stopped working.
I think its the motor [SD 19 72 15] but could be the battery board
[15-1200-00 rev b ?]
Can it be replaced, otherwise the scope is still great !!!!!!!!!!!!
Thank you Phil        UK
Mike here: See the articles "Fixing a Motor Unit Failure" and "Motor Fault fix" on the Helpful Information: Telescope Tech Tips page; they may (or may not) be of assistance. If you need a replace board, Meade is the only source for those. Suitable motors may be found in hobby shops or online. You can try Telescope Warehouse (link on the Astronomy Links page) as well.
Subject:	Alt-Az home position
Sent:	Wednesday, March 2, 2011 11:39:57
From:	Charles Hall (
It's been a while since I used my ETX-70 and I just re-learned something
I read a long time ago. In order to prevent the ETX from bumping into
it's built-in azimuth hard stops when GOTO'ing, you have to start from
the correct orientation. An addendum to my old Meade manual for the #497
says in effect:

1. Release AZ clutch and rotate scope fully anti-clockwise. 2. Now
rotate clockwise until the scope tower is over the control panel. 3. Now
point the scope North; the control panel should be on the left side of
the scope.

In trying to figure this out the other night I first looked at the
downloadable PDFs from Meade, and the ones they have don't mention this
at all.

Shouldn't this be mentioned in every "Alt-Azi" and "Polar" home
instruction? Or is this unique to the old ETX-70s?

Maybe I just missed it. I can tell you it's very mysterious to hear the
motor running, and not see the scope turning!

Mike here: I believe the original ETX-70EC had hard stops (the control panel is on the base) but the ETX-70AT (control panel on a fork arm) doesn't have AZ hard stops. So, the OTA is just leveled and pointed towards True North.


Ahhh, that explains the mystery. Looks like I better keep my original
manual around!


Subject:	etx 105 thumb screw
Sent:	Tuesday, March 1, 2011 22:06:30
From:	Kris Parrott (
Aloha- I have inherited an ETX 105 that is missing its eye piece thumb
screw. Any suggestions where to find one. Meade was unable to help. Also
I am upgrading the software that was bundled with the telescope ( Starry
Night pro 4.5) to their pro plus 5.0. Is this or any computer interface
software designed to direct display images from the telescope to the
computer screen in real time? Lastly, what is the fastest cable connect
for that model to Mac OSX.
I look forward to exploring our Hawaiian skies.
Kris Parrott
Mike here: First, please read the Electronic Mail Etiquette item on the ETX Site home page; there are reasons I request that "Message Text" not have mixed questions. Thanks for understanding. For your screw question, see the item "Q. What is the size of the eyepiece holder screw?" on the ETX FAQ page. Planetarium software will not display images from cameras or imagers. You will need software appropriate to your camera or imager to display an image from the telescope on your computer. For more information, see the Helpful Information: Astrophotography page. The RS-232 port on the AutoStar #497 runs at 9600 Baud. However, you will need a USB-serial adapter unless you have a RS-232 card on your Mac. But not all adapters work reliably with the AutoStar. I recommend Keyspan adapters for Mac and Windows.
Subject:	RE: ETX125PE Dec lock 'flop' problem.
Sent:	Tuesday, March 1, 2011 05:37:51
From:	Brian (
Thanks for the response. I used the article you referred me to to
dismantle the mount.

When I 'kicked' the tripod leg it was so minor a bump that I doubt it
would have knocked a star out of the fov had I been looking. The tube
just dropped and when you see the picture you will see why.

I have done some more investigation. The plastic debris was machining
swarf from where the groove was milled out. It wasn't cleared out before
the thing was assembled! Meade, would we expect anything else?

Secondly, the area of 'damage' in the groove is not 'worn', it is
'pressed' as if a force has been applied against the 'upper' stop which
NEVER happens when I use the scope; however, when I lift it out of its
Meade aluminium case, I have found I lift it by the base and by the
tube. As I store it with Dec lock unlocked, I assume this slight
pressure has caused the groove to deform or it was damaged in some way
by the previous owner; the post must be made of cheese. It is strange
that it has only just come to light after three or four years of use.

You can see in the rather badly focussed picture attached, that the
groove has a 'wide' section and the plastic is pushed up into a ridge
where the wider  section is.

It looks as though the groove needs to be enlarged and lined with a
steel U-shaped piece to spread the load and to stop this happening
again. However, I doubt if I can make such a small part and may end up
trying Araldite or plastic metal to effect a repair. There is an old
saying that 'for a ha'porth of tar the ship was lost' and this is the
classic case of that.

Do you know if RTA's are available from Meade?

More anon,

Regards, Brian


Mike here: At one time, for older ETX telescopes, Meade would provide a replacement RTA. But the last I heard, they have stopped that practice.


More. I gave up and took the RTA to the local engineering shop who are
re-making the plastic post in steel to re-use the original worm wheel,
lock piece and bearings. It's going to cost more than 48c but it will be
a one-off, never give any more trouble and lock perfectly solution. The
guy took one look at the 'engineering' of the parts and shook his head,
muttering '******* Chinese workers!' I told him it was made in the good
ol' USofA and he didn't believe me. Pity I don't have one of the older
designs to show him.

I'll send photos of the finished machined part in a few weeks.

Regards, Brian

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