Last updated: 29 January 2001

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:	 Resolution - ETX90 EC tracking
Sent:	Monday, January 29, 2001 13:26:03
From:	Rob.Fezekas@dfafunds.com (Rob Fezekas)
Just wanted to let you know that my tracking problem is solved. For no
real reason, I put the mode screw back in my hand controller and
instantly the motors began to track and my mode button works fine once
again. Now I just have to press the "mode" button every time I start up,
press the "speed" key to get into Northern Hemisphere Polar Aligned mode
and I'm back in business. I wish removing the mode screw would make NPA
the default setting, but this is only a minor inconvenience.
Thanks for your suggestions.

From:	sherrodc@ipa.net (Clay Sherrod)
Bob - GREAT!  Glad you got it working, now you can get down to some
serious observations!  It sounds like your hand unit had already been
ELECTRONICALLY defaulted to the Polar Mode, and taking the screw out has
by-passed the command (see Page 11, "Electronic Controller Modes" in the
Meade manual). This certainly is no problem but appears that someone has
pre-set the hand control (at the dealer or factory?  seems a bit
unlikely, though - perhaps someone tried it out prior to you getting
it).  By putting the screw back in (bet you didn't try the motors BEFORE
you took the screw out!) you defaulted back to what the handbox was set
to, taking it out overrides that setting.

In any case.....you're up and running!  Best of Luck!
Clay Sherrod

Subject:	 RE: Right ascension motors with handbox
Sent:	Tuesday, January 23, 2001 10:35:32
From:	Rob.Fezekas@dfafunds.com (Rob Fezekas)
To:	sherrodc@ipa.net ('Clay Sherrod')
Thanks for your tip. I tried to follow your instructions but
unfortunately, I couldn't get it to work yesterday but maybe that's
because I don't really understand how to implement your step #3 below. I
am still a novice. Could you spell it out in greater detail? I have the
scope mounted on the standard field tripod with the N labeled leg
pointed toward the north and the top mount tilted to 34 degrees (Los
Angeles latitude). I believe this is polar alignment.

What exactly is "observing position" and how does that differ from Polar
Alignment? What do you mean by "outside of alignment position"?

And when you say in #3 to aim the scope toward north do you mean pick up
the whole tripod and physically move it until the scope is pointing
north or do I use the arrow keys to rotate the scope north?

Also, I'm not not sure if we have the same problem. I have two problems-
(1) even with the correct mode screw removed, the scope will not track
objects automatically (the motors are silent) and (2) the speed and
direction keys work fine on my hand controller, but the MODE key does
absolutely nothing, no matter how long I hold it down.
Thanks again,
And more from Clay:
From:	sherrodc@ipa.net (Clay Sherrod)
Rob -
Glad you got back to me; sorry you are still having trouble, but I think
we can get you going.  I read back through my response to you and,
indeed #3) is confusion.  Let me clarify some of your points.

1)  Refer to page 13 in your Meade instruction manual and look at the
photo at the top right; you will see an ETX 90 with tabletop tripod
aimed at Polaris.  Now imagine that being your scope, except you are
mounted on the Tripod.  This is "Home Postion" for your scope in Polar
Mode (which is where you want it with the standard hand controller). 
Notice the two tabletop legs "under" the scope base?  You have two
buttons where those would go on the base of your scope; MAKE SURE that
those two buttons are in the same position as the legs seen in Fig. 16
of the manual.

HOWEVER, the eyepiece is pointing UP in this picture; when you first
mount the scope on the tripod and aim the tube toward Polaris (90
degrees), it is likely the eyepiece will be pointing "down", opposite
what is showing in Fig. 16.  To reach "Home Position" as is shown in
Fig. 16, proceed:

2)  Notice that the CONTROL PANEL is aimed at you in this figure; this
is correct, and should be pointed north for home position.

3)  While in this position (Figure 16, except your eyepiece will be
pointing "down"), go ahead and ROTATE the scope in the RA axis ONLY
COUNTERCLOCKWISE until you hit the hard stop; do this slowly (about 180
degrees should do it....just keep gently turning counterclockwise until
you hit the stop).

4)  Once there, begin rotating BACK, or CLOCKWISE until the fork arm is
OVER THE CONTROL PANEL (as in Fig. 16) and the eyepiece is aimed "UP",
as seen in Figure 16.

5)  Now your are in Home Postion.  Once here, rough align - sighting
down the barrel toward Polaris to due north; make sure you have your
latitude set for 34 degrees (which I think you said you did).

6)  Once Polaris is very close, use your finderscope (make sure it is
aligned to the main scope) to center Polaris on the cross hairs.  TO DO
THIS use the slow motion vernier controls ON THE TRIPOD.  Move the
entire scope...DO NOT use the arrow slew keys; the scope must remain
fixed in home position!

7)  Once centered in the finder, center (using the tripod adjustments)
Polaris in the big scope (I prefer to use about 100x for this).  Once
centered, look up and find the END STAR (the last star of the "handle"
of the "Little Dipper" and slightly offset the scope using the tripod
adjustments TOWARD that star.

8)  Here is where I confused you:  Once your are aligned, you are ready
to observe.  What I was inferring to "observing position" was similar to
Figure 13, Page 12 of your Meade Manual (right photo), where the scope
is aimed overhead, or to some other region of sky besides
Polaris....nothing complicated, just get it looking somewhere besides
Home Position!

9)  At that point you can test your slewing in both axes; MAKE SURE THEY
ARE ADEQUATELY CLAMPED so that motion can be immediately detected in
both RA and DEC when slewing.

10)  SOMETIMES the RA drive motor will kick on immediately after slewing
but usually not.

11)  After slewing, if you still do not hear the RA drive (it is loud),
then hit the "SPEED" key and press any speed, say "3".  Now slew at that
speed in BOTH  axes.

12)  Wait a few seconds and RA motor should engage; if not, repeat Step
11 and hit "Speed" and try another speed; slew again and listen.

13) Hope and pray this works....it does in many cases, reminding the
motor that all is set up and ready.  If not, you may have a problem but
not a serious one.  Let me know ASAP and we will pursue.

controller does not do much once you have removed the screw for Polar
Mode. It is used to flip-flop between the modes, which you do not need
(keeps you from tracking when viewing terrestrial things).  Also, HIT
MODE if you have an "Electric Focuser" plugged into the base of the
scope, and it allows you to focus (1 slowest, 4 fastest).  ONCE FOCUSED,
press "Mode" again, and you are back to slewing and selecting slewing

Let me know if this helps.  Good luck and good seeing.

Clay Sherrod

Subject:	 Re: tripod and electronic controller
Sent:	Saturday, January 20, 2001 21:10:06
From:	jchalfen@goldengate.net (John Chalfen)
To:	tfmf@bellsouth.net,
Just happened to have my ETX 90/EX and electric focuser out as I read
your message. Simply pressing the in and out buttons on the standard
controller should operate the electronic focuser. I would try it with
the Autostar and see if works. If it doesn't work with the standard
controller or Autostar, then it's more than likely in the ETX itself. if
it does work with the Autostar, then it is the standard controller.

--Sometimes I think that the surest sign of  intelligent life on other
planets is the fact that they haven't tried to contact us yet.  (Bill
Watterson, Calvin & Hobbes)



Subject:	 Right ascension motors with handbox
Sent:	Saturday, January 20, 2001 10:58:21
From:	sherrodc@ipa.net (Clay Sherrod)
To:	Rob.Fezekas@dfafunds.com
Rob, I saw your inquiry on the ETX web site - ain't it great? - and
thought I would respond since I, too sometimes prefer to use the
standard control box when looking at one object in particular and do not
need GO TO.

Interestingly, the problem you are experiencing seems to be a circuitry
idoscyncracy of sorts that is fairly common; mine had the same thing and
I learned quickly how to fix the problem:

1)  First, it won't go away; you will have it every time you fire up for
the evening.

2)  Align scope (I think you said you were using Polar) and get all set
up.  Lock clamps and use arrow keys to slew in both RA and DEC to assure
that clamping is secure;

3)  Once satisfied, move scope to "observing position," outside of
alignment position with scope aimed toward north (be sure to check "home
position" to keep internal wires from wrapping!);

4)  PUSH THE SPEED KEYS (#1-4) and select ANY speed;

5)  Go back to your arrow keys and slew again.  Scope motors will

Hope this works for you...if your slewing capability is there, I am sure
it will.  There seems to be some sort of recognition failure for the
motors to engage (I assume from what you said that you removed the
APPROPRIATE screw from the bottom of the handbox?  There are two, one
for north and one for south hemispheres; either way, the motors should
be heard - unless you removed the WRONG screw....there are four (4) of

Best of luck and good skies - 
CLAY SHERROD,  Conway, Arkansas

Subject:	 Electric focuser with handbox
Sent:	Saturday, January 20, 2001 10:50:17
From:	sherrodc@ipa.net (Clay Sherrod)
To:	tfmf@bellsouth.net
Hi - saw your message on Mike W.'s ETX site and thought I would take the
liberty of writing.  That's great you got the electric focuser as a
bonus, quite a deal.  You will thank your lucky stars every night using
it; it elimates much vibration and frustration.

You, can, indeed interface the focuser directly to EITHER the standard
control box that comes with your EC scope or with the Autostar.  With
the hand control box, there are four settings for focus, using the
number keys, with "1" being the slowest.  Simply plug the focuser coiled
wire into the BASE CONTROL BOX of the ETX scope at either female jack
(you will see the appropriate jack size - there are two that will fit; I
use the RIGHT on, looking at the Control Panel, so the cord does not get
in the way as much).

IMPORTANT NOTE, and MIKE TAKE NOTICE!  A problem with the electric
focuser (Meade) is that it should be DISCONNECTED from its power source
after every use (each evening).  They have a tendency to drain your
batteries (if plugged into the scope) or battery (9v if using the
handbox supplied with the focuser) overnight.  I have experienced this
first-hand and have heard from many who also have.  Simply unplug the
coiled cord each night.

If your connect to the Autostar, the focuser still plugs into the
Control Box, but you have 9 speeds to choose from "1" still being the
slowest; on that unit, simply depress and hold for 2 seconds the "MODE"
key and you will see the first display as "FOCUS"; if not the first
display, SCROLL down five spaces and there it will be!

Good luck - Clay Sherrod, Conway Arkansas
And a reply:
Eureka!  Perhaps I'm the first one dense enough to have missed all this,
but at the same time, the electronic focuser came with no instructions. 
With both of your messages I knew I had to be missing something,
sooooooooo...  I took a few more minutes of close inspection and
discovered what you already knew.  The coiled wire can be disconnected
from the focuser control box-  (I know I know, but I never noticed this
before).  Naturally it is now plugged directly into the ETX control box.

Furthermore, I completely concur with Clay's suggestion on disconnecting
the focuser.  While using the 9V box, I have run through a battery each
night!  And not from use-  simply from leaving it connected to the 9V! 
I thought it might be the cold but as it has warmed into the 40's this
no longer made sense.  No question that the power source is drained
overnight!  And as it is now plugged directly to the ETX, I am of course
leaving it disconnected when not in use.

Thanks for pointing out the obvious Clay and Mike!

Subject:	 electric focusing
Sent:	Friday, January 19, 2001 23:44:37
From:	rseymour@wolfenet.com (richard seymour)
TO:   tfmf@bellsouth.net (tfmf))
Plug the focus unit into one of the AUX jacks on the base of the ETX.
(either jack... they're wired in parallel)

Now the hand controller buttons should operate the focuser.

(unless something is broken)


Subject:	 Question power supply ETX90-EC
Sent:	Friday, January 19, 2001 00:53:19
From:	rohloff@mpia-hd.mpg.de (Ralf-Rainer Rohloff)
because the original MEADE power supply is very expensive I've bought an
stabilized power adapter (12V, max 1.5A) with a complete set of
connectors for only DM 30.
What connector type fits to the ETX90-EC ?
Where is positive, the central pin on the ETX ?
Can something smoke or run the motors only in the wrong way ?

Many thanks in advance.

from Heidelberg, Germany

P.S. Great ETX site !!!!
Mike here: There are several power supply discussions on the Tech Tips page. In several places it notes the center pin is positive. You may want to read through those as not all power supply adapters will work reliably.

Subject:	ETX-90 New User Question
Sent:	Thursday, January 18, 2001 14:40:23
From:	MarcusKay@aol.com
What an incredible find your site was!!! I'm a complete ETX-baby.
Annointed with one for Xmas and have such a basic question, I'm almost
embarassed to ask. I just got the AutoStar, but haven't even set it up
yet.(rain and clouds here for the last two days...bleccch) However - it
seems from alot of the info on your site, that the scope has some way to
go into 'tracking' mode. (even without the Autostar?). I can't seem to
figure out how, once I've got the scope centered on an object, to have
it 'track' it automatically (as the earth spins). Am I just imagining
this capability? Am I misreading something? Am I just confused?

Thanks in advance,
Marcus Dinsmore
Washington, DC
P.S. My company's involved with a great new program. I bet alot of your
readers would be interested. Check it out! www.spaceadventures.com
Mike here: The EC model can track (compensate for the Earth's rotation) when the ETX is mounted equatorially (same as polar mode) and the standard handcontroller is set for polar. When you add an Autostar the ETX can track whether mounted in polar or Altitude/Azimuth mounting; you just have to tell the Autostar which mode to use. Of course, with the Autostar it gets a little more complicated for the GOTO capability since it has to know some facts about the date, your location, etc. I've seen info about these adventures. I've been to 45,000 (Air Force T-38) but always wanted to go higher! Nice to know an insider... So, when does an ETX go up?

Added later:

Thanks for the hint Mike. Though I'm still a tad unsure how to 'turn on'
the tracking function...I'll try to figure it out once the clouds clear
out here in DC. As far as when the EXT gets to 'go up', I think the
bigger questions is, when do we?!
Mike here: Without Autostar: tracking gets turned on when the ETX is turned on IF the default mode is polar. Otherwise, it turns on when you set polar mode from the handcontroller. With Autostar: tracking gets turned on at the completion of the alignment process.

Subject:	 Can't get into polar mode
Sent:	Thursday, January 18, 2001 11:51:10
From:	Rob.Fezekas@dfafunds.com (Rob Fezekas)
I've been using my new ETX-90 EC since October without any problems.
Recently however, I noticed I could not use the mode key on the standard
controller to get into polar aligned mode. The scope would not
counteract the earth's rotation and the slight tracking noise went
silent. Holding the mode key down for even 30 seconds had no response,
although the batteries seem OK because slewing with the direction keys
still works fine. I even removed one mode screw to change the default to
PA but still it won't counteract the earth's rotation and the gears are
silent. I've turned the scope on and off several times and even took out
the batteries and replaced them. Is there a quick fix I'm not thinking
of or is it time to contact the dealer?

Thank you.

-Robert Fezekas
Mike here: If the scope slews in RA but won't track in RA then there is something wrong somewhere. Can you slew at the slowest speed? If the RA lock is too tight (or there is binding someplace) this might show it.

Subject:	 tripod and electronic controller
Sent:	Wednesday, January 17, 2001 19:22:57
From:	tfmf@bellsouth.net (tfmf)
what a gem your site is-  especially for a relatively new ETX90EC user! 
I have 2 questions here-

1.  I purchased the scope with the standard electronic controller and
the dealer also threw in the electronic focuser.  Here is where I'm
confused.  I have properly attached the focuser and it works just fine. 
However, the standard elec controller also seems to have buttons for
focusing (the "in & out" buttons I presume).  Do I in fact need both
keypads, and if not, how do I get the std controller to operate? 
Pressing those buttons achieves nothing.  (I also have an autostar but
do not plan to attach it until I am more comfortable with my own
knowledge of the sky).

2.  Have read through all the tripod hints.  I happen to already own a
Velbon DF-50 tripod and was wondering if any of the adaptors mentioned
on the site could also be used with this tripod.  It has a 3-way quick
release platform made for 35mm and video cameras, as well as pan
tilt/vertical/horizontal movement.  I would love to use this tripod if I
could adapt to the ETX90EC.

Again, thanks for a great web site!

Mike here: Not having the electronic focuser myself, I can't say from experience but according to the documentation it is supposed to work through the standard handcontroller. Scopetronix has some tripod adapters that may work. Word of caution: the tripod really needs to be a very sturdy one, otherwise vibrations will make observing hard or impossible.

Subject:	 RE: Did I Damage my ETX's Drives..??!
Sent:	Sunday, January 14, 2001 20:58:35
From:	jchalfen@goldengate.net (John Chalfen)
To:	MFRiesco@directvla.com
Unless Meade changed the way they connect to the worm gear, the answer
is no.

This is how the worm gear is on my ETX:

From the motor is a gear train, and at the end of the train is a gear(I
know...Duh). This last gear has a tapered hole in the center. The end of
the worm gear that attaches to the last gear in the train is tapered and
fits into the hole, and a screw holds the worm gear in place. This
causes a friction type lock which allows the scope to move unless a hard
stop is hit. When that happens the motor and gears keep turning, but the
worm gear stops moving. I had to put my worm gear back on because I let
it hit a hard stop and keep turning and the screw fell out. Sounds right
from what I remember, since I did this awhile ago.

--Sometimes I think that the surest sign of  intelligent life on other
planets is the fact that they haven't tried to contact us yet.  (Bill
Watterson, Calvin & Hobbes)



Subject:	 etx90-ec comments
Sent:	Tuesday, January 9, 2001 10:06:02
From:	acoholic@onlink.net (Andrew Coholic)
I purchased my ETX90-EC with teh autostar back in October of last year
(2000).  Immediately, I was surprised at how easy it was to operate,
even the autostar, and I tried to use it as much as possible before the
cold and snow arrived (I live in Northern Ontario, Canada).  Even with
the sub zero temps now, I pull it out to do some quick observing a few
times a month.  I have also used it for primes focus photography on the
moon, and got some excellent shots (2 24 exposure rolls) of the december
25th partial, which was absolutely awesome form our location (approx. 50
north lat).

I just have to say, my ETX has performed wonderfully, even at allmost -
40 degrees (drive running for about 1 hour).  After reading about the
problems many have had with the right tube adapter, I have made a simple
aluminum bracket on which I can mount a counter weight, to offset the
weight of the camera in either prime focus, OR piggy back.  When the
camera/adapter is mounted at prime focus, I have an aluminum bar (.25 by
1 inch) in which I have tapped 1/4-20 theads about every 1 inch.  I
place this on the piggyback mount, and place the weight (that I got with
the JMI piggyback mount) out over the front end of the scope untill it
balances perfectly.  Then, only a light tightening is required to lock
the OTA in the forks.  If I want to piggyback, I mount the same aluminum
bar under the scope where the weight is supposed to go, and move the
weight out untill it also balances.  I think if the OTA is allways kept
in good balance, there will never be a great enough load on the clutch
to do any damage, right?  This is an easy fix.  When I first mounted my
OM-1n with a 50mm lens onto the ETX, even with the seemingly heavy
counterweight you get with the JMI mount, it did not balance out.  With
a heavier lens like a 200mm, it would be WAY too nose heavy, and with
the camera on the prime focus adapter, it would be way too tail heavy to
use without having to super tighten the ra lock.

Thanks for your great site!

Andrew Coholic
Kirkland Lake, Ontario Canada

PS. my other scope is a B&L RV5+ and I swear I can see more with the ETX
90, even with the smaller apature.

Subject:	 Did I Damage my ETX's Drives..??!
Sent:	Monday, January 8, 2001 06:28:24
From:	MFRiesco@directvla.com (Riesco, Michael F)
Arrrrggghh!!  I did something stupid, and I'd like to know if I
potentially did any damage to my new ETX-90EC's azimuth drive.

The "home position", as you know, involves placing the scope tube level
(which I did), and rotating the assembly fully counterclockwise until
reaching a stop, then clockwise until the fork is over the control panel
area.  Unfortunately, I mistakenly reversed this latter part -- I turned
it fully CLOCKWISE until it hit a stop, then counterclockwise until the
fork was at the right spot.  I then pointed the whole thing North, and
off I went.

By sheer coincidence, when the Autostar then slewed the scope to find
reference stars, it actually did stop near existing stars, which I
centered, per procedure.  The scope then pronounced the alignment

When I then told the Autostar to "GO TO" a desired object (Saturn), it
slewed the scope in azimuth toward where it "thought" Saturn would be.
Suddenly, the motion stopped (obviously it hit the rotational hard-stop,
though I didn't realize this at the time, since I didn't know yet that I
had done the alignment wrong).  I thought that something was just
"catching up" in the gearing, so I let the motor just keep buzzing away.
I let this continue for about 10 seconds, then shut it off -- so, for
those 10 seconds or so, the motor was grinding away, "pushing" against
the hard stop!  What's worse, I then re-aligned the whole thing again,
and I caused this hard-stop hitting problem to happen AGAIN!

I obviously know what I did wrong, but my question is:  Did I damage
anything by letting the motor buzz away against the hard stop?  Or is
there some  kind of "idiot-proofing" in the design that releases some
sort of clutch to prevent motor (or gearing) damage?

Anxiously awaiting your reply.....and thank you for putting up with
novices like me!!

Mike Riesco  (mfriesco@directvla.com)
Mike here: If the scope moves fine in azimuth using the slewing controls on the Autostar or standard handcontroller you should be OK. So try that. If OK, then put the ETX in the PROPER HOME position and try aligning again. If the scope tracks smoothly then you didn't damage the gears. If there are LARGE jumps or skips then the gears may have been damaged. Let me know how it turns out.

And another response:

From:	sherrodc@ipa.net (Clay Sherrod)
Mike -
Thanks for your questions.  My best guess is that your scope and drive
motors are OK; let me answer your second concern first, that being the
locking of the Azimuth (aka Right Ascension) knob.  On many scopes it
take quite an effort to tighten the AZ knob to the point where the drive
motor is engage.  Here is an ideal rule-of-thumb:

If the scope moves (slew it back and forth a couple of times BEFORE
aligning at north.  If the scope moves in both directions with little or
no hesitation, your clamp works just fine.  You CAN, however,
overtighten the knob.  Unknown to many, and cleverly disguised by its
silver paint, this clamp is PLASTIC and can break.  So be careful.  Back
to locking in Azimuth: If you find that you are tightening fully and the
scope does NOT move when slewing, then you can remove the clamp and and
adjust some.  If this is the case, you undo the set screw on the clamp,
remove the clamp in the "tight" position and replace further toward the
"unlocked" position; this gives more latitude in clamping motion.

As to your "running into" the stop position, it sounds like you might
not have the scope in the "HOME POSITION," which is a confusing thing to
many new users.  Just remember this:  Home Position is found by making
sure that the two plastic cover screws on the BASE that cover up the
holes for the Table Top tripd are facing equally NORTH, one sort-of on
each side of north, if that makes sense.  This puts the COMPUTER CONTROL
panel (with your plugs, off-on switch, etc.) directly WEST.  This is
important; that places your base stops in the right position.  If the
base is turned any other direction, you will, indeed, run into stops.

Once your base is so aligned (just remember that the control panel goes
WEST, and that does it!), aim your scope so that the Declination circle
is aligned directly OVER the west-facing control panel.

1)  NOW, rotated the scope counter-clockwise until it hits a stop; that
should take the optical tube aim just almost, but not quite south.  It
will NOT make a complete 1/2 turn, as most people think.

2) After that merely rotate the tube again until the Declination circle
is over the control panel on the base; the scope should then be pointing
due north (or close).

3) NOW YOU PROCEED TO ALIGN, starting with your scope tube level (use a
bubble level) and set your Dec. circle to 0 degrees once level; tighten
the decl. circle knob to hold.  Now align with Autostar.

Okay, if - when you turn the scope counterclockwise (step 1) and it
keeps going on around past half-way (past due south), then your azimuth
motion has turned too much from your first attempts.  You must carefully
"unwind" the azimuth (clockwise) on the base until you can place that
first stop just west of south as described in step 1, above.  I doubt
this has happened, I think you simply have misinterpreted the "home
position;"  it is a common problem.

NOTE:  If you can HEAR the azimuth motors, and they slew the telescope
(set it up inside, initialize your autostar and do some "dummy
alignments" to activate the motors and play around with it), then your
drive motor in AZ is okay; if, however, you cannot hear them, nor do
they move the scope when properly clamped, you may have a
problem.....but I doubt it.  They are tough for their sizes!

Best of luck; let me know how it turns out!

P. Clay Sherrod
Conway, Arkansas
And more:
Subject:	 From:	sherrodc@ipa.net (Clay Sherrod)
To:	MFRiesco@directvla.com (Riesco, Michael F)
Mike -
Unfortunately, there is no "fail safe" mechanism inside the RA (Azimuth)
drive other than the clutch itself.  The clutch, of course can slip
under pressure, but that depends on how tight you had the azimuth clamp
secured; if it was not engaged too tightly, then the clutch rightfully
would have slipped in such an occassion.  I feel that this is the case
since your motors did not fail altogether.  Likely, if the motors had
fatigued under the stress you would have gotten the message:  "Motor
Failure" on your Autostar readout.  You obviously did not, as the motors
would have shut down as soon as the message appeared.

I think you are okay; if you would like to verify, simply take the scope
out, (clamp both axes securely) align (from "Home Position" this time!)
and turn it to a bright star at medium power.  Go inside and relax and
come back in 15 minutes and see if your star is close (you'll probably
get a little drift, so don't worry about that).  Another way, without
going outside is to do a "fake alignment" indoors; simply set scope in
home position, level tube, clamp axes.  Initialize your Autostar for the
actual time when you do this, and today's date (or whatever day you do
this - that way, the scope will be realistic and pick stars that it
knows are in the sky at that exact time and date). Make sure your clamps
are engaged so that scope will move with motors.   Now do an "easy
alignment."  After first beep (after scope moves), hit "Enter' and scope
will move to second alignment target and beep again.  Hit "Enter" again,
at which time motors will engage. Leave scope where it is pointing, DO
NOT UNLOCK the azimuith clamp and move your RA setting circle (the large
one that slips) to read "0 degrees" on the little pointer.  Go away for
30 minutes and see if the pointer has moved 30 minutes on the setting
circle.  If it has, your motors are working great!  I think you are okay.

Let me know what you find....Clay Sherrod
-----Original Message-----
From: Riesco, Michael F (MFRiesco@directvla.com)
To: 'Clay Sherrod' (sherrodc@ipa.net)
>Hello Clay --
> Thanks for the very quick reply!  Yes, I knew that I had mis-set the
>"home position", and I know where my error occured (I moved things
>first, THEN counterclockwise, as opposed to the other way round).
> My concern was more that, given that I drove the azimuth motor/gears
>into the hard-stop and then waited 10 seconds or so before turning the
>OFF, did the motor (or gears) get harmed?  I think, like you say, that the
>answer is "no", since everything seems to work just fine even after the
>incident.  It would just make me feel better to know positively that there
>is an actual mechanism in there (i.e. a clutch, or something like that)
>is specifically intended to prevent damage in such a situation by
>disengaging the motor from the gears, and just letting the motor spin
>until the user turns the power off.
> If you know of such a "fail-safe" design feature, please tell me, so
>I can stop worrying about having "stressed" something...!
> Again, thanks for your kind advice...
> Mike Riesco  (mfriesco@directvla.com)

Subject:	 New ETX-90EC
Sent:	Saturday, January 6, 2001 14:09:41
From:	dschre@goodnet.com (Richard Schreiber)
I discovered your Web Page just prior to my purchase of an ETX-90EC a
few days ago, and it (1) validated my decision and (2) gave me some
confidence knowing there was easy access to knowledge and experience
with the scope.

First some comments on the scope.  It was not an auspicious beginning. 
The scope appeared to behave properly using the hand control, but then
started to have slewing problems.  It would slew (ALT mode) very
rapidly, regardless of the speed setting, for the first second or so,
and then settle down.  It was o.k in AZ mode.  I contacted the dealer
and he led me through the use of the Autostar to check the drive motors
more thoroughly.  Slewing seemed fine.  Then came the first night we set
up to observe.  Easy align went fairly smoothly, we saw Saturn and
Jupiter and then were slewing to the western skies (to see what, I
cannot recall).  The mechanism suddenly stopped and a drive fault
message appeared on the Autostar unit.  We tried what it suggested, and
even tried recalibrating the motors, but the scope would not slew at all
in ALT mode by this point.  A quick call to Meade and they suggested I
exchange at the dealer, which I did.

Part Two: The new unit seems to be ok, but notice as I was setting up
today, it takes a second or two to start slewing in AZ mode (under
manual mode, not clocking).  At slower speeds the delay is somewhat
longer. Also the base seems noticeably tighter (when turned manually in
the unlatched poition) than the original unit. If you stop slewing and
then continue in the same direction, the delay is minimal; if you
reverse direction the delay shows up again.  In addition, I do notice a
slight continuous clicking noise when it moves in the AZ mode in the
counterclockwise direction (this is in additional to the normal whine
heard in all directions ALT and AZ).

Do you think the above symptoms are anything to be too concerned about,
i.e. signs of problems down the road?  Otherwise - and this was just
terrestial use today - the slewing seems to be fairly even and at the
right speeds. And calibration and training showed no faults. In the ALT
mode none of the above symptoms are apparent with the other drive motor.

Any comments/advice would be most appreciated.  Thanks!
Mike here: The delay is movement is the backlash in the gears. A small amount of this is normal with the ETX (and NexStar) telescopes. Stiffness may be a result of tighter nuts, less lubrication, or just lack of use. Whether this is good or bad depends. Keep using it and see if it loosens up (which may not be good either).

Subject:	 right tube adapter
Sent:	Saturday, January 6, 2001 10:33:52
From:	mbailey@northcoast.com (m bailey)
Great site! I learned through your site what my problem was with my
declination lock (right tube adapter) It was exactly as you described
and photographed. It snapped off and I did not overtighten it. It too
broke when I wasn't using it. And I've only used it a handful of times.

I'm very distressed with the ETX 90ec. I am a fairly experienced 'scope
user having used many types over the years and after several frustrating
and fruitless nights, I have yet to get my autostar working properly. I
can't imagine a neophyte successfully using this telescope.

Perhaps foolishly, I suggested my wife buy one for here science
classroom. She did and it immediately developed drive problems and had
to be sent back (where they replaced it with a new one.) So that makes
THREE ETX 90ec's that I've had direct access to. 2/3 of which developed
major problems after essentially only a few minutes of use. I dread
having ever been exposed to these seeming beauties. I've spent far, far
more time dealing with repairs than actual viewing. I'm totally bummed
out by the whole deal. Now I have to go back to the drawing board and
find the new "ideal telescope" for my needs all over again!


Mark Bailey
2110 Greenwood Heights Drive
Kneeland, CA 95549
Mike here: Sorry to hear about your problems. Fortunately, not everyone has this problem. As to the Autostar, there are reports on my site and elsewhere about "neophytes" using the system without problems. So, user experiences do vary.

Subject:	 RE: ETX-90EC Questions
Sent:	Saturday, January 6, 2001 07:49:07
From:	MFRiesco@directvla.com (Riesco, Michael F)
Thanks for the reply, Mike!  As I said, the strange behavior with the
hand controller was only intermittent.  last night I was out with it
again, and it didn't re-occur at all.  But still, it's one of those
annoyances where you don't know when/if there will be more problems in
the future.

Otherwise, I couldn't be more pleased with the scope.  Beautiful views
of Jupiter and Saturn (easy objects to find manually).  Tonight I will
try the Autostar for the first time.  And I've decied to go ahead and
replace the #140 Barlow with the more conventional shorter-barrel #126,
which is the one recommended for the ETX-90EC anyway.  Hopefully, it
will be able to do double-duty with my son's refractor as well...


     Mike Riesco.

Subject:	 RE: ETX-90EC
Sent:	Saturday, January 6, 2001 00:22:14
From:	webecold@alaska.net (Wm Smith)
Thanks for the quick reply.  Yes I have read the numerous positive
things said about the ETX line, and no I have not encountered any
problems (I have only had it out of the box to play with for about an

A friend of mine owns an ETX-90EC and loves it so much he convinced me
to buy one.  I have been looking at scopes (all types and makes) for 25+
years now and decided my sons birthday, he's turning 11, was a good
excuse to buy one.  I  guess you could say I am just a little paranoid
about spending the money, although Kits Camera had one heck of a deal at
$595 for the ETX-90EC with the deluxe field tripod, no shipping, no

I need to look at this as an investment in my childs education!

Bill Smith
Added later:
In all seriousness, how are the motor drives of EC models holding up? 
In your opinion, are the reports of problems more an exception rather
than the rule for reliability?
Mike here: If you consider that the user comments of problems that are sent to me are just a small part of the tens of thousands of ETX models that have been sold since its introduction, and if you consider that people tend to report the negative versus the positive, I'd say the problem reports are small percentage-wise. But then I have no way of knowing the overall return rate (to dealers or Meade). Of course, if your scope has a problem, it is no consolation that most other users are happy with theirs.

Subject:	 ETX-90EC
Sent:	Friday, January 5, 2001 17:13:18
From:	webecold@alaska.net (Wm Smith)
I just purchased an ETX-90EC for my son's birthday (read-Dad's when he
gets bored with it in 6 months) and now I'm a little concerned.  With
the negative things I am reading about the drive system of the EC, did I
make a mistake in purchasing this model, or are these types of problems
to be expected with any drive system?

Bill in Alaska
Mike here: Did you read the positive things as well as the negative? There is a lot to like about the ETX line. Are you experiencing any problems?

Subject:	 ETX-90EC Questions
Sent:	Friday, January 5, 2001 08:47:40
From:	MFRiesco@directvla.com (Riesco, Michael F)
Happy New Year!

I got a "90EC" for Christmas (!), and wanted to ask you a couple of
things relating to the scope:

1)  I haven't tried out the Autostar yet, and have just been playing
with the normal hand controller.  I have found that, on occasion, when I
have the speed set to one of the slower rates and I push the right- or
left- arrow, it causes the ETX to slew in azimuth at the HIGH rate for a
second or two, then settle down into the desired lower speed.  This is
annoying, because you then have to "slew back" in the original direction
to get back to where you wanted to be.  Any thoughts on this?  It only
happens occasionally, and I'm wondering if this is cause to exchange the
scope for a new one or not.

2)  When the scope is pointed at or near vertical, it is very hard to
access the focus knob (I'm sure this is obvious to anyone who has ever
used the scope, but, again, I'm new to the ETX world!).  I know that
there is an electronic focuser available by Meade (and others?), and
that there is also that mechanical, flexible thing you can attach to the
focus knob to avoid having to squeeze your fingers under the tube to
access the knob directly. Any recommendations in this department?

3)  Regarding Barlow Lenses, I bought the Meade #140 (apochromatic, 2X).
This is a relatively long-barrel design, and results in my having to
turn the ETX's focus knob clockwise almost all the way to achieve proper
focus, at least with the 26mm eyepiece.  It is also totally unusable
with my son's smaller Celestron 60mm refractor (no matter how far you
turn the focus wheel, you cannot achieve proper focus when using that
Barlow Lens).  I had intended to get a Barlow Lens that would be usable
with both scopes, and it appears that this one (the #140) is not.  Do
you think that the Meade #126, which is physically shorter in length and
which is the recomended one for the ETX, would also work properly with
the 60mm refractor?  Any thoughts/guidance would be much appreciated.

As always, thanks very much for your help, advice, and Website!!

Mike Riesco  (mfriesco@directvla.com)
Mike here: That is odd behavoir by the standard handcontroller. I'd suggest checking to see if happens when slewing with the Autostar handcontroller. If so, you know it is the drive, not the controller. Certainly an electric focuser is a nice luxury if you don't mind paying for it. But there are alternatives, including a "clothes pin" clipped to the focus knob. I don't know if the #126 will work with your Celestron.

Subject:	 90EC questions
Sent:	Friday, January 5, 2001 08:41:05
From:	henr0188@tc.umn.edu (Jonathan C Henriksen)
I exchanged my defective ETX for one that works. I have no problems with
the motors now. The Autostar seems to work great so far, but I have not
had time to align it and try the all-important Go To Function yet. Do
you recommend trying to polar align it first or should I start with the
altazimuth align? Also I had the ETX-90EC out a few days ago and it was
about 10 degrees out. When I brought it back in, I did not put the lens
cap on first and water condensed on the scope, including the front lens.
I left it in the warm air so the water could evaporate. When it was
done, the water left a few water spots on the front lens. I don_t think
the water spots are affecting my view through the telescope, but I don't
like them there. I want to clean the front lens, but the users manual
gives more warnings than descriptions on how to clean the optics. What
is the proper way to clean it with out damaging it and without leaving
more water spots? Thanks - Jonathan
Mike here: Most first-time users have better results with the Alt/Az mode. As to cleaning, see the info on the Buyer/New User Tips page.

Subject:	 ETX-90EC Electronic Controller Question
Sent:	Wednesday, January 3, 2001 04:55:35
From:	hollandj@mail.ci.tlh.fl.us (Jim Holland)
I got a 90EC for Christmas and have been playing with it - mostly inside
and have not yet experienced any of the drive motor problems mentioned
frequently at your web site. And yes the site is a great wealth of info
on the ETX - thanx.

I completely read the manual and then started to explore the scope with
the manual at my my side. When I got to the part about modes, things did
not go so well. When I would push the mode key (hold it down for
extended time), the controller would not do what the manual said. ie the
top two lights would not come on. I then looked at the back of the
control unit and apparently the both mode screws are missing as well. My
assumption here is that the scope is in the alt/az mode. I've got the
#883 field tripod on back order - but when it comes - how would I change
to polar mode??? I also have the handheld computer(astrostar???) but
have not explored it yet.


Jim H
Mike here: The screws affect the default mode but as I recall you should be able to set the tracking mode via the control panel as well per the manual instructions. (I currently don't have an EC model to try out)

Subject:	 ETX-90EC - laptop computer control
Sent:	Tuesday, January 2, 2001 10:18:41
From:	Rick@ht.com (Rick Cunningham)
Great site!  A real service to the community!

I'm a newcomer to astronomy trying to decide whether to keep the ETX-60
with autostar that we bought the family for christmas or to return it
for an ETX-90EC.  Autostar is incredibly useful (but lithium batteries
might be needed to stand up to the cold), but I'd really like the better
optics.  The 90EC is double the price (worth it) but unfortunately comes
without autostar.

The problem I'm having is understanding whether it's possible to get
starfinder capability from a laptop (or desktop!) computer without
having to shell out the $150 for the handpiece.  On the 90EC, without
autostar, is there any way to get RA tracking while mounted in alt/az
(level)?  And can the scope be driven from the computer to a particular
dec/ra coordinate? I know the autostar does a bit of magic with
mechanical backlash on the encoders, but this can be overcome pretty
simply.  If there's no Meade software, is there a movement among users
to develop something that provides the basics of computer controlled go
to and ra tracking?
Mike here: As has been pointed out on the site, the Autostar is required for computer control until someone writes an Autostar emulator for a desktop/laptop computer. And no one has publicly or privately told me they are doing this. Any takers out there? And yes you can get the EC models to track in Right Ascension with an Alt/Az mounting and no Autostar. Unfortunately, you have live at 90 degrees latitude for the telescope to accurately track real objects in the sky! ;-)

Subject:	 ETX90EC Alt Problem
Sent:	Monday, January 1, 2001 18:53:11
From:	DWitherill@email.msn.com (DWitherill)
I have been reading all of the post about the Alt failures on the
ETX90EC.  Just thought I would add that I had the same problem with
mine.  Setup fine and then the Alt motor quit and didn't even make a
sound.  I sent the unit back to Meade and it seems to be working fine
now.  Sounds like a manufacturing defect to keep showing up over and
over again.

Henryk Zels is probably correct that the wires are being cut by the
gears.  Hopefully Meade has changed the process.

David Witherill
Port Charlotte, FL

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