Last updated: 31 May 2001

This page is for user comments and information specific to the Meade ETX-90RA (originally known as the "ETX Astro") and the ETX-90EC. Comments on accessories and feedback items appropriate to other ETX 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 and I'll post them. Please use an appropriate Subject Line on your message. Thanks.

Subject:	Horizontal slewing
Sent:	Wednesday, May 30, 2001 4:53:53
From:	payrolls@ix.netcom.com (Kyle)
I am having the same problem as John Luciano (see May 7 posting) where
the motor is working but the horizontal movement is sluggish or
non-existent for a while before I get a quick, catch-up, movement which
usually overshoots the point I am trying to reach.

My question, how far clockwise should the hortizontal lock be swung in
order to lock?  It seems to tighten at about the 6 o'clock position but
I think maybe it should be tightened all the way.  But after reading
some of the posts and the manuals warning regarding the vertical lock, I
am hesitant out of fear of breaking something.

A P.S. - when I click on email or on your address, 36 windows pop up
saying "page not available" - clicking STOP has no effect.

Thanks for the great site.
          Kyle Bonney
Mike here: The horizontal lock lever is not meant to move all the way to the side of the triangular cutout it sits in. However, if it does go all the way to side and you feel like the lock is not fully engaged, you need to reposition it so that it reaches a locked position before reaching the full movement. If your scope is new you might try just moving the scope horizontally back and forth through full rotations (hard stop to hard stop; if you have an ETX-90EC or ETX-125EC); that might loosen up the grease and improvement the movement. As to the pop-up windows, that is nothing that my site causes. Clicking on my email address at the bottom of a page should only do what your browser has been configured to do with a "mailto:" command.


Thanks Mike for your prompt reply......

Yes, I do have a new ETX 90-EC (sorry for not being clear).  I thought
that since the horizontal movement is so erratic and the motor sounds
like it is running pretty hard for the little movement I see, that
either I have the horizontal lock too tight (preventing movement) or too
loose (not fully engaging the clutch).  If I tighten further (past the
halfway point) do I risk any damage?  Tightening less didn't seem to
make much difference (worse, if anything).
        Kyle Bonney
Mike here: You should not overtighten the lock (as that can cause damage) but that is a hard to define concept. Move the lever until it is difficult to move more. It _could_ still move more but this last movement requires more effort.


Thank you again, Mike.  I'll try it!

Subject:	Re: ETX 90 Motor problem
Sent:	Saturday, May 26, 2001 20:09:10
From:	JPit@Prodigy.net (Jeff)

Thanks for your help.  I reset and retrained the scope and it seems to
be working okay now.


Subject:	etx90ec
Sent:	Saturday, May 26, 2001 15:39:51
From:	lawler@cybertrails.com (richard lawler)
Is it possible to separate all the stars on the Astronomical Society's
Double Star list using the etx90ec w/auto star?
Thank you.
H Lawler
Mike here: I don't know what all the double stars they have listed are but the theorectical resolving power of the ETX-90 models is 1.3 arc secs.

Subject:	ETX 90 Motor problem
Sent:	Saturday, May 26, 2001 2:50:01
From:	JPit@Prodigy.net (Jeff)
I recently purchased an ETX 90 EC.  It wasn't tracking properly but I
was able to determine what the problem was.  If I set the AZ to 0 and
moved the scope clockwise with the autostar the degree readings were
fine.  When I moved the scope counter clockwise the number degrees given
in the read-out was way off.  The scope was moving 180 degrees but was
only registering about 70 or 80 on autostar.  Is there some type of
sensor that may need replacing?

Thanks for your site and all your help!
Mike here: This does sound like an encoder problem on the drive. I suggest you contact the dealer for an exchange (depending upon how recent is "recently purchased"). Alternatively, contact Meade.

Mike here again: In thinking more about your email I began to wonder if you have TRAINED your Autostar. If not, do that. TRAINING is a necessary step in matching an Autostar to its telescope. Also, before you TRAIN be certain that the right telescope model is selected in the Autostar setup menu.

Subject:	 ETX 90 vertical lock problem
Sent:	Wednesday, May 23, 2001 16:38:33
From:	dbjarnas@toronto.cbc.ca
My optical tube on my ETX 90 EC is not held securely in place. I tighten
the vertical lock but it doesn't tighten the OTA and it sags downward.
Any thoughts?
Many thanks
Mike here: It sounds like your Right Tube Adapter has failed. Contact Meade for a replacement. I detail the replacement at the bottom of the page of my initial ETX-90EC comments. It is easy.


I've contacted Meade as you suggested. The replacement is on its way.
Many thanks, Mike.

Subject:	first time telescope question?
Sent:	Saturday, May 19, 2001 16:21:40
From:	jdclagle@earthlink.net (Joe Lagle)
Your web site is really informative, but I just wanted to ask for your
opinion.  I'm looking at purchasing a etx 70, and wonder if it would be
better to go with a 90 instead, but am leary of spending that much money
on a first telescope.

Thank you
Mike here: First you have to decide just WHAT you want a telescope to do. If you want to see planets and the Moon and brighter galaxies and nebulae then a small telescope will do fine. If you want to see details on planets or fainter objects then you will have to consider a telescope with a longer focal length and larger aperture than the ETX-70AT. See my report on the ETX-70AT on the Helpful Information: Buyer/New User Tips page.

Subject:	ETX Astro Question
Sent:	Friday, May 18, 2001 16:33:10
From:	reinehr@sprynet.com (Bill Reinehr)
Hope you can help me out or point in the right direction for some
additional information.

I have recently acquired an ETX Astro Telescope (actually, my brother
bought it but when anything ever goes wrong, it mystically becomes my

I do believe the motor drive was in working condition when he purchased
it. I have followed the Meade instructions (locked down both axis) but
the motor drive does not engage when I turn it on. I've let it run for
about 5 minutes with no results. I can hear it whirring away quite
quietly in there. Also tried fresh batteries but no luck. The manual
slo-mo controls work just fine.

Any help appreciated.
Thank you.

Bill Reinehr
Mike here: If the model is the "EC" model and not the "Astro M" model (and since you say you have slo-mo controls I assume you have the EC model), then its startup default is set for terrestrial use. You can change this from the handcontroller for each session or "permanently" by removing the appropriate screw from the back of the handcontroller. See the ETX-90EC manual for details on changing the startup to polar mode.

Subject:	Binding focus on the ETX90 EC
Sent:	Wednesday, May 16, 2001 12:49:30
From:	Gene_Rozea@Rollsys.com (Rozea, Gene)
Thanks to the wealth of info and links I decided to approach the binding
problem. I loosened the three screws holding the OTA to the housing and
the four on the housing. Then gently "wiggled" the OTA while rotating
the focus control back and forth. I easily found a point where it
rotated smoothly. At that point I re-tightened the three rear screws,
slowly going around the clock. Then the four on the sides and the focus
is smooth form one end to the other. I don't understand how the binding
got built into the scope to start with, but all the hardware was tight,
the box was sealed. Anyway, all appears to be well - now if this drizzle
would let up.....

Subject:	Spontaneous Action
Sent:	Monday, May 14, 2001 7:11:44
From:	peter.a.giordano@mail.sprint.com
Please help if you can....

I have been having problems with my ETX 90 when I am tracking something
the scope will just randomly point up or down for now reason. It did
this on occasion earlier this year but I thought it was the cold
weather. It seems like now it does it every time I try to use it. Any

Pete Giordano 
Mike here: Is this occurring with the standard controller or the Autostar or both? If with the Autostar, can you update to the current version? Also, how is the battery level? If the problem still occurs after installing the newest Autostar software (and a RESET and RETRAIN) and the battery level is OK, then you may need to return it to Meade; see the Meade Announcement on my Site Home Page.


I have used brand new batteries and I am using the AutoStar. I will
update to the latest version of the firmware and see if that helps.
Thanks for the fast reply.

Subject:	ETX 90 Optics Catastrophy
Sent:	Wednesday, May 9, 2001 11:23:41
From:	Lang.Michael@Orbital.COM (Michael Lang)
Oh Mighty Weasner:

I have a very old ETX-90-RA.

I bought it from a nut who back-packed it into a desert, got caught up
in a sandstorm, and well, you can imagine the results.

I have rebuilt and modified this unit until it barely resembles the
stock-ETX 90 RA that it was before the sandblasting.

And I have more mods in the works.

The post-desert trip optics "were" fine until:

1. The previous owner attempted to remove the front meniscus lens from
it's cell and scratched it,

2. The front lens baffle decided to snail-walk it's way toward the
earths core (i.e., it fell off) for the current owner.

I contacted Meade about replacement optics. They will not sell them to
me as I am (apparently) not empowered with the super-human skills
necessary to replace and re-collimate the optics. (Curious, I've been
pretty good at this for that last 5 years with the old optics set)

They did offer to repair the unit, but after describing it's condition
and modifications, suggested I bury the unit and purchase a new 90 or
125 EC.

Well ! (snort !)

Eventhough I can re-mount the baffle, and the primary didn't get
touched, I would like to take this opportunity to replace the front
lens, because of the scratch. It's not much of a scratch, but I've made
significant mechanical & electronic modifications to this little ETX,
and I love it. I just want "more" perfection in the optics.

So, sir, I come to you as the undisputed expert of ETXdom, do you have
any idea how I can con, cajole, or coerce a replacement front lens from
anyone in the free world ?

Sincere appreciation,

Mike Lang
ETXless in Virginia and weeks from Mars opposition......
Mike here: I can relate to your desire to keep the old ETX. I still tend to use my old ETX-90RA over the other scopes. As to getting a replacement lens, well, you can certainly watch the FOR SALE ads on my site and elsewhere. Maybe you'll get lucky.

Subject:	web-controlled ETX90's
Sent:	Tuesday, May 8, 2001 22:40:18
From:	rseymour@wolfenet.com (richard seymour)
To:	veghead@webmail.co.za
one of the ETX Web-Ring (nav.webring.yahoo.com/hub?ring=etx&list) sites has exactly that
(in theory... i've never seen it online).
An ETX90 controlled by user web resquests.

Prowl through the 40-odd sites (it's one of the early 27) 
and you may find that site.  (i haven't probed it for about a year).
It used to be an obvious link on the left side of their main page.

good luck

Subject:	ETX-90 Motors
Sent:	Monday, May 7, 2001 13:13:20
From:	John.Luciano@cgiusa.com
I recently purchased an ETX-90EC from Natural Wonders. I am new to
Astronomy but I have been resarching these scopes. I would like to know,
when I use the arrow keys on the controller to move the scope
horizontally, the motor hums but seems to hesitate before the scope
moves. I don't have this problem when I move it vertically. Is this the
slop I've heard of or do I have a deffective scope? Any information
would be greatly appreciated and thanks for a great site.

John Luciano
Mike here: There is some slight pause while the gears take up the backlash. It shouldn't be excessive however.

Subject:	Re: flip-mirror control problem
Sent:	Sunday, May 6, 2001 12:37:52
From:	veghead@webmail.co.za (Jaco Beukes)
Thanks for the help Mike ! I took the telescope back to the dealer where
we discovered that the mirror somehow came loose and was falling around
inside the telescope ! I exchanged it for a different one. I thought
that there was a problem with the new one as well until I discovered
that I didn't remove the lense cap :-)

Another question ... I want to write software to hook my ETX 90EC up to
the internet and allow people to take photos via the web. Do you know if
there is a
(1) application programming interface for the Autostar
(2) free downloadable database of astronomical objects ?

Thanks for your time and help once again.

Jaco Beukes (veghead@webmail.co.za)
Mike here: Regarding interfacing to the Autostar, there is some information on the Autostar Information page on databases as well as the LX200 command set.

Subject:	flip-mirror control problem
Sent:	Tuesday, May 1, 2001 05:04:15
From:	veghead@webmail.co.za (Jaco Beukes)
i bought my first telescope (ETX 90EC) a week ago. i set the whole thing
up as soon as i got home, only to discover that i'm unable to switch the
flip-mirror control to the "up" position. i can't move it past
approximately 45 degrees and when i look through the eyepiece only about
25% of the view is light. it would be a bit funny if i hadn't been
dreaming about using my own telescope for so long. i'll only be able to
take it back to the shop next weekend, as i'm working in norwich (2
hours from london by train) during the week.

my question is : am i overlooking something ? is the flip-mirror control
supposed to work like this or is the scope defective ?

thanks for your time, help and the great forum.

jaco beukes

programming : an artform that fights back.
Mike here: I would guess that something is getting in the way and preventing the flip lever from moving through the entire 90 degrees that it needs to move. Exchanging the scope is the best course of action.

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Copyright © 2001 Michael L. Weasner / etx@me.com
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