Last updated: 28 November 2000

This page is for user comments and information specific to the Meade ETX-90EC. Comments on accessories and feedback items appropriate to other ETX 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:	 ETX90EC Electronic Focus
Sent:	Sunday, November 26, 2000 18:47:23
From:	art621@earthlink.net (Art & Paula Morales)
I received a Mead Electronic Focus #1244 with the purchase of my
ETX90EC.  It works great when I start it up, but while tracking in polar
mode, it does not respond.  I use the standard controller only. I
noticed it with battery only and then purchased a 1 amp 12v power supply
from Scopetronix.  The problem is still there.  With those little motors
running I can slew ok, but cannot focus.

What's wrong?  Is the power demand greater than 1 amp?


Subject:	 Can I ask you a quick question?
Sent:	Tuesday, November 21, 2000 19:03:41
From:	rschlack@optonline.net (Robert Schlackman)
Sorry to bother you.  I am wondering if you can answer a quick question
for me. I have a fair amount of slop in my RA slewing.  I've followed
the directions from Jordon Blessing, but do not have a grasp on what the
potential is for tighting up the drives.  Evertything seems tight inside
my scope.  At speed 5 it takes about 2 seconds for my scope, ETX90ec, to
start slewing.  At speed 3 it takes a good 9 seconds to start slewing. 
After the slewing starts, it's smooth.  When switching to the opposite
direction, I need to wait again.

How much slop is exceptable for the ETX90ec?

Mike here: This is backlash. It does take some time for the gears to mesh and start moving the scope. Yours does seem excessive however. Certainly much worse than I recall seeing when I had an ETX-90EC and worse than the ETX-125EC I have.

Subject:	 solar filter for ETX-90EC
Sent:	Tuesday, November 21, 2000 11:54:27
From:	bernie.j.verreau@intel.com (Verreau, Bernie J)
Hi, I've read some of discussion about solar filters for ETX - and seen
photos in the gallery - and am persuaded to give one a try for general
observing and eclipse photography.  Have a couple questions for anyone
who might know...

I prefer the orange-tint optical glass filters to the blue mylar
variety. Thousand Oaks Optical is a suggested source.  Their ad says:

"WHAT SIZE DO I ORDER? The sizes are listed by aperture (size of the
lens or mirror). The filter is mounted in a polished aluminum cell
designed to fit over the end of the tube. Specify the brand, model and
outside diameter (OD) measurement of telescope tube. Most filters are
lined with felt and/or have extra felt included for a custom fit.
Telescope manufacturers often make changes to the tube size, so the OD
measurement is important. All filters including reduced aperture are
ready to use."

I was wondering if anyone has ordered such a filter based on Meade's OD
measurement of 4.1" for the ETX-90, and with what result?  Fits or
doesn't? Satisfied with the filter or not?

I also wondered if tracking the sun with Autostar is a problem.  As I
recall, the goto function refuses to point directly at the sun - or am I
imagining things?   Thanks in advance,

Bernie Verreau, Redwood City, CA
Mike here: See my review of the Thousand Oaks filter at:
When I ordered I just asked for the ETX model. So ask for the ETX-90 model. You can track the sun reasonably well by using the same technique I mentioned I used this week at OPT's Meade Day. Just do a "blind align" by accepting the alignment stars as centered. Then slew manually to the Sun. Be certain to cover the finderscope before pointing the ETX at the Sun.

Subject:	ETX90EC - slewing problem
Sent:	Sunday, November 19, 2000 20:15:41
From:	CCohen4391@aol.com
I'm new to astronomy and grateful for your site. I just purchased a new
EXT90EC and set it up as soon as I could.  I also purchased the autostar
controller, but so far have only played around with the eletronic
controller that comes with the unit.  Question:  The controller works
the horizontal directions fine, but only down with the vertical arrow. 
When the up arrow is pressed the motor just hums, but the telescope
doesn't move up.  Any suggestions?  I've been using it with the
controller for horizontal movements, and manually for vertical by
unscrewing the vertical lock.  I searched for info. in your search files
but couldn't find anything except to references that Meade sometimes has
problems with their gears.  I'm otherwise thrilled with the ETX90 - it's
just very cold at night in CT this time of year. Thanks, Zach
Mike here: With the Declination axis locked can you move the tube in declination? If so, then you may have a problem. If not, then when you reposition the tube at any angle you can move down but not up? If there is a DEC axis problem, contact Meade; they will probably send you a free Right Tube Adapter repair kit. It is an easy fix.

Subject:	 Using the very portable ETX for taking QTVR!
Sent:	Sunday, November 19, 2000 14:08:04
From:	goran.thisell@sentec.se (Gran Thisell)
I really like my ETX90EC!! (Have also a somewhat cumbersome G9,25)
Brought it to my summer place this weekend - its so simple to set up!
Had nice wiews of Jupiter and Saturn and very late the Moon!

Came to think of.. You can use the ETX in daylight as well to create
fantastic panorama-photos. Got this idea today - and have already
programmed my ETX for it (it seems to accept a lot of "landmarks" so no
problem there..)

You know QTVR? Its Quick time virtual reality.
A good starting point might be www.kaidan.com/

However you have the means already with your ETX CE.

1. Mount a wery wide field camera piggy back (15-35mm.)(I am using the
upward-pointing hole, and some 1 1/4" part fitted to the camera..)
2. Create "landmarks" in your ETX CE - equally divided for 360 degs and
for your cameras angle (10-20 shots..) Best is to mount the camera for
3. Shoot your pan.
4. Develop, scan and let some of those fantastic sofwares "stich" it all
together. (vrtoolbox, photovista, corel photo paint 9...
5. Publish it on your site or print out a nice 360 deg of your wiew..


Subject:	 Question ETX
Sent:	Sunday, November 19, 2000 05:11:50
From:	rparsons@thedomain.md (Rick Parsons)
I have a ETX90 and the RA drive motors aren't turning the unit even
though the RA Lever is locked. Twice I've seen it move about 1/4" but
that is it. I've tried the train, reset, and calibrate functions to no
avail. Do you think it's broken?

Thanks for any info.

Rick Parsons
Director Technical Services
dotMD, Inc.
678-524-9043 cell
Mike here: Do you mean you can't slew the ETX in RA using the handcontroller or Autostar or do you mean that the scope doesn't automatically track in Right Ascension? In either case one possibility is that the RA lock is not fully engaging. A tip that others have suggested is to remove the RA lock lever (when the lever is about midway in the groove) and reposition closer to the fully unlocked side. This will give more travel on the locked side. Let me know if that helps.

Added later:

Yes, I mean that it won't slew either with my handcontroller, or with
the autostar. I can't get it to polar align because it won't move.
Either manually or using go to doesn't work.

I've tried unlocking the RA lever and turning the scope in 1/2 inch
intervals and relocking the lever and trying to get it to move but even
after going all the way around from both stoppers it won't budge.

Your note below, is that what you were saying I should do- or do you
mean somehow adjust the RA lock lever does that involve taking this

Thanks for your help, I'd really like to see something other than the
moon, as I bought the barlow 2x and also a 6mm lens - and some mountain
property in n. georgia. ha :)
Mike here again: I gather that when you try to slew you hear the motor drive running but the scope doesn't rotate. Lets try one more thing: when you lock the RA can you still rotate the ETX by hand (not with the controller)? Don't force it; just see if it moves easily. If so, then adjusting the position of the lever is possibly all that is required. There is a setscrew on the side of the lever. Loosen that, lift the lever up off the shaft, and then put it back onto the shaft with the lever pointing more to the unlock side, then retighten the setscrew. Then move the lever to the locked position and see if you can still move the tube by hand; if so, you might have to repeat this operation of repositioning the lever. If the RA finally locks then try the controller.


Right, I can hear both motors running, but when locked it won't move at
all. With the lever locked I can't move it. Thanks - I guess it's going
to have to be sent to Meade for repair.
Mike here: bummer.

Subject:	 ETX 90
Sent:	Tuesday, November 14, 2000 06:18:13
From:	MREYNOLDS@expl.com (Mike Reynolds)
I received an EXT 90 from Scope City today.  My first impression is that
it is larger and heavier than I expected.  Now on to the adventure in
unpacking it and getting it ready for first light..

Mike Reynolds.

Subject:	 ETX motor problem response
Sent:	Monday, November 13, 2000 21:43:52
From:	rabuffy@peoplepc.com (R Arroyo)
This is the first time I've written in to your site, I have to say it's
great and well appreciated. This is in response to someone having a
problem with the RA drive starting after they turn on the scope. The
message was about the ETX90, but I've had the same problem with my
ETX125EC with the electronic focuser.  I just use the standard hand
controller, I hope to purchase an Autostar in the future. There doesn't
seem to be a direct cause for the problem, but mine starts doing it when
I change the batteries, after they wear down, it hardly happens at all.
It sounds like the scope goes into polar mode even when the screws on
the controller are firmly in place. Other times this has happened is
when I turn the scope on outside in the cold weather, but not always,
like I said, it seems to happen at random. However, what I tried one
time was to disconnect the hand controller from the base of the
telescope whenever this happens, after about two or three seconds
everything stops. I then reconnect the hand controller and everything
seems to work fine. The RA motor stops running, the buttons for the DEC,
and RA motors work when you push them, and the electronic focuser which
is plugged into the base works as well (it works even with the RA
problem). I've done this several times, and it doesn't seem to affect
the scope any. Maybe it's voltage surge, maybe it's the cold, I don't
know but hopefully this will be of some help.

Subject:	 Tips
Sent:	Monday, November 13, 2000 15:49:49
From:	wbowens@att.net (Bill Owens)
Although I've only just started in Astronomy (3 days now) with my
ETX-90EC I've come up with a couple of hints that might be useful.

I already had a Bogen 3021 tripod with a 3047 head.  However, the quick
release plate on the head interfered with the lip on the bottom of the
ETX. I discovered that a 3.5 inch floppy is almost exactly the thickness
of the lip and makes a good shim.

I also have a Garmin GPS receiver which makes getting both my current
position and the time a snap to determine and enter into the Autostar

Hope these tips are useful.


Subject:	 ETX motor problem
Sent:	Saturday, November 11, 2000 17:01:04
From:	slider2253@msn.com (slider2253)
First off great site, it has really been helpful. I received my ETX 90
about two weeks ago and have been very pleased with it. However tonight
when I turn it on after the scope does it's initial slewing, the motor
continues to whir but the scope is not moving. I am not pushing any
buttons the scope is doing it on it's own. I would say it sounds like
the low speed slew but the scope is not moving at all that I can tell.
What could be causing this? Any info would be appreciated. I also just
put in new batteries. Thanks.
Mike here: You didn't say whether you are using the standard handcontroller or the Autostar. But from your description it sounds like what you are hearing is the Right Ascension drive running normally to compensate for the earth's rotation. In order for any telescope to properly track objects in the sky like the planets and stars, the telescope has to move very slowly. Just like the hour hand on an analog clock, it takes 24 hours to go completely around. Is this what you are seeing?

Added later:

I am using the standard handcontroller. I don't think the telescope is
tracking anything because it starts when I first turn it on. Then if I
slew to something the noise stops for a few seconds then starts again.
It sounds like it gets stuck in the slow slew speed. It doesn't seem to
do it all the time and as of late last night it wasn't doing it. Could
this just be an isolated incident and nothing to worry about?
Mike here: With the standard controller you can set the default mode (tracking ON or Off). If it is ON then you will hear a motor noise whenever the power is ON. If it is OFF then the only time the motors run is when you slew the telescope using the handcontroller. Check the manual for setting the default mode. You can also change it using the handcontroller (see the manual).

Subject:	 Correct power supply
Sent:	Wednesday, November 8, 2000 15:55:24
From:	kardrak@hotmail.com (Eduardo Lopez)
Is very confusing to me understand what kind of power AC adaptor i need
for my ETX 90EC...  I read the feedback but some people says 12volts
with 200ma  other  says  12v with 1000ma   ... others with 1.5A !!

I am using a power adaptor 12v with 300ma and the telescope works except
because the velocity is always the same althought i change it !

It works with the fastest velocity with the adapter but when i return to
use batteries the telescope works perfectly!  so what is the correct
especification for a power AC adapter?

Greetings from Mexico City
Mike here: I agree. What works for some does not work for others. Some even suspect that the Meade adapter has a problem. Of course, some adapters perform differently too under load and no load. Check through the Power Supply topics on the Tech Tips page; also do a search on "power supply".

Subject:	 re: el cheapo ETX90/ec's ... on eBay
Sent:	Friday, November 3, 2000 21:34:37
From:	rseymour@wolfenet.com (richard seymour)
I haven't bought one there, but it appears like there may be a Meade
dealer selling new-in-box ETX90/ec's on eBay.

He usually has two or three running as "no reserve price" autctions, and
there are over 50 extremely-satisfied-customer comments about his
service, promptness and willingness to take back inappropriate items (he
sells other things than ETX's, too). The only "old auction" i bothered
to back-track ended up at $380 as the closing price.  Which is a -great-
price for a new ETX90/ec.

(#497 Autostars seemed to be selling for about $132)

So, the above is sorta hear-say, but a lot of folks mention in their
notes on Mike's site (and elsewhere) that they got their ETX "on

--dick (not low-mileage, needs work, reasonable amount of rust)

Subject:	 ETX 90EC photos
Sent:	Wednesday, November 1, 2000 14:38:16
From:	msp01339@isd.net
I am wondering if you can tell me where to find some photos taken with
the 90EC scope?  I see a lot of photos on your site, but I want to be
sure what scope was used.
Mike here: Most of the images were taken with the ETX-90 models (either RA or EC). Only a few were taken with the ETX-125EC and that should be noted in the description.

Subject:	 ETX 90EC Price
Sent:	Wednesday, November 1, 2000 14:35:21
From:	msp01339@isd.net
I saw an ETX 90EC priced at $356.88 yesterday and I am wondering if that
is an incredible deal that I should jump on, or if that is average.  It
seems pretty good to me, but I really don't know.  I'm not sure what is
included for that price, but what would need to be included for it to be
a good deal?  A quick responce would be appreciated since if this is as
good a deal as it sounds it may not last.
Mike here: Where did you see the deal? Is it a new scope from a reputable dealer or a used system? If new and complete with Meade 26mm, finderscope, and the standard handcontroller, it is a good deal.

Added later:

I went back to check it out again today.  Turns out only the display
model was that cheap, and it was kind of beat up.  Oh well, I'll just
keep looking. thanks for responding so quickly.

Mike here: Sorry to hear that the deal wasn't as good as you hoped.

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