Last updated: 30 April 2008

This page is for user comments and information of a general nature or items applicable to all ETX, DSX, and DS models. 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:	small plastic gear
Sent:	Tuesday, April 29, 2008 19:56:16
From:	Glenn Craig (
Sorry to bug you but I am looking for a replacement for this gear that
got eaten by a worm gear that was way too tight. This little gear (shown
in photo) is (or was)a 24 tooth- the last small gear before the final
worm drive on an ETX90EC.


Does anybody have these things?
Thanks for your time,
Glenn Craig
Mike here: Try ScopeStuff (link on the Astronomy Links page).
Subject:	focus control disappeared on ETX 125 EC
Sent:	Tuesday, April 29, 2008 16:18:22
From:	Graham Young (
I wonder if you please could help, I have an ETX125 EC and without
warning, the focus knob loosened (grub screw),and came off,!!! Then the
connecting focus "bar", slowly disappeared inside the tube. please have
you any suggestions, Can I simply take the back off the tube, and push
it back through, I would greatly appreciate your veiws, many thanks
graham , oswaldtwistle,lancs, UK
Mike here: See the article "Focus Shaft Fix" on the Helpful Information: Telescope Tech Tips page.
Subject:	EXT-125 power panel issue
Sent:	Monday, April 28, 2008 10:59:14
From:	Blue Moon Woodcrafts - Peter Perrone (
I saw your site and figured maybe you have some suggestions for me.  I
got my 125PE used but seldom at best.  The original owner never used the
included AC adapter.  I tried it and when turned on it smoked that part
of the power panel circuit board that the jack is soldered to.  The
scope still works fine via the internal batteries.  I checked with Meade
and they will only repair the scope if it's sent to them, they don't
provide parts.  It's simple enough to replace the panel so do you know
where one can be bought?  I'm also considering wiring the jack to the
internal battery lead connection points on the board but can't tell if
the jack wiring passes thru any resistors or other circuits on the
board.  The power supply is the one sold by Meade as an accessory and
its output is 1.5 amps.  Thanks for any help you can provide.
Blue Moon Woodcrafts - Peter J. Perrone
Mike here: It sounds like the polarity might be have been reversed on the AC adapter or on the ETX control panel. As to a replacement, you might try Telescope Warehouse (link on the Astronomy Links page). There is a battery cutoff switch, that cuts power from the batteries whenever an external power source is connected.


Thank you very much I'll check it out.  Do you know which post on the
panel jack should be positive, center or side?

Blue Moon Woodcrafts - Peter J. Perrone
Mike here: As noted on the FAQ page, the center pin is positive.


I just checked the power supply output itself and the polarity was
reversed on it.  So much for made in Taiwan.  I reversed and resoldered
the connections and things seem to be working OK now.  

Thank you again, very much.

Blue Moon Woodcrafts - Peter J. Perrone

Subject:	ETX Dust Cover Thread
Sent:	Monday, April 28, 2008 08:27:21
From:	Patrick Mullarky (
Love your ETX site!
I'm trying to track down a spec. for the ETX 90 and ETX 125 dust cover
threads for a project and possible product.

I checked a huge number of articles and references, but came up empty
regarding any actual specs.

Of course, I could simply measure the threads, but considering the
trouble some people have even removing the "standard" dust cover, the
thread measurements (and finish) are somewhat critical.

Where would you start looking for some kind of thread spec. ?

Patrick Mullarky
Kirkland, WA
Mike here: Don't have that info.
Subject:	re: Mead ETX125 circa 2006
Sent:	Sunday, April 27, 2008 20:44:51
From:	richard seymour (
You wrote:
> 2. We undid the az, rotated by hand counter clockwise till it hit the
> stop, moved the tripod so the tube pointed polar north and level.

First error: you should rotate the tripod so that the power panel
is facing -west-.
For an LNT-equipped scope (if it offers Auto Align (not Easy)
it has the LNT module (it's in the red-dot finder)), leave
the scope fully CCW.  If it does not have an LNT, point the
scope due north before clamping that axis, leaving the power
panel facing West.

> 5. Speaking of backlash, I searched everywhere for settings and found
> none, so I could not adjust them, which is probably a good thing.

Backlash is set by doing the Train Drives procedure,
found under Setup>Telescope>Train Drives
It's probably an appendix in the manual.

Performing that procedureshould markedly help your GoTo's

have fun

Subject:	melting the glue for the secondary mirror on an ETX?
Sent:	Sunday, April 27, 2008 18:36:20
From:	Guy Brandenburg (
I looked at your website on ETX's. An acquaintance of mine has a Meade
compact scope of some sort - he didn't recall which - that he said his
step-parent left in a car trunk on a trip from the deep South to
Washington, DC. It got so hot that the glue (or whatever) that holds the
secondary in place melted and the secondary slid down the corrector
plate. He is not sure whether it was an ETX (a maksutov design), and
thought it was a SCT of some sort. Any idea what they glue these
secondaries on with?

Guy Brandenburg, Washington, DC
My home page on astronomy, mathematics, education:
or else

"Education isn't rocket science. It's much, much harder."
(Author unknown)
Mike here: See the article "ETX-90RA Secondary Baffle Fix" on the Helpful Information: Telescope Tech Tips page. However, it will likely be required that the ETX optics will need to be recollimated. This is not a task to be undertaken lightly as it will require a lot of patience and perhaps assistance. It may be best to contact Meade for the repair. But it you want to undertake it, there are collimation articles on the Telescope Tech Tips page.
Subject:	Gap in ETX-125EC RA mount
Sent:	Sunday, April 27, 2008 11:02:23
From:	John C. Sun (
My pre-owned ETX-125EC shows a gap between the top and bottom halves of
the RA mount.  Functionally the mount works perfectly, but would you
happen to know what had been modified on this scope that resulted in
this gap?  Attached is a picture for clarity.

Thank you for your time.


Mike here: If there is no wobbling about the vertical rotational (azimuth) axis then you might not want to worry about it. The only thing that could happen is that the RA setting circle tape might fall out. Mine did a long time ago but that didn't bother me since I never used it anyway. On the other hand, if there is wobbling then the base could be loose on the central bolt.
Subject:	Mead ETX125 circa 2006
Sent:	Sunday, April 27, 2008 08:56:31
From:	Dan Newell (
Can you offer advice on aligning a Meade 125etx?  We were almost
successful but let me tell you what we did and maybe you can spot our
error.  I used to be a Celestron employee just before the lawsuit so I
am well versed in the North and Level technology, or so I thought.  I
may have just enough knowledge to be dangerous, so here it goes:

1. Being purchased in 06 this scope may or may not have the new tech. 
It had the GPS unit and I was wondering if that might be creating a
conflict; I think we may have better luck turning off the GPS and
entering data manually.  What is your take on this?

2. We undid the az, rotated by hand counter clockwise till it hit the
stop, moved the tripod so the tube pointed polar north and level.

3. We tried updating the data in the hand control with standard time and
setting to PM, military time and neither made a differrence.

4. In centering the alignment stars we tried to use the up and right
arrow keys to eliminate backlash and that did not seem to help.

5. Speaking of backlash, I searched everywhere for settings and found
none, so I could not adjust them, which is probably a good thing.

6. We made sure the tripod was level.

7. Aligned the finderscope so we could hopefully choose the correct
alignment star.

8. We used a nice power supply, charged, plenty of amps, tip positive,
the works.


After doing the above setup procedure, we used the auto align and the 2
star manual align as well as the quick align.  We were given align
successful messages in the auto and the quick align, but not the 2 star
manual, so I will stick to the auto align.

After aligning, slew commands were off, but oddly it was not consistent.
For that reason I cannot say it was off 15 degrees (daylight savings),
trying to go below the horizon (AM vs PM maybe??)
Mike here: Several comments. First, current and past ETX models do not have GPS, at least not from Meade. Did you mean the LNT module (which does not have GPS capabilities)? Have you done a CALIBRATE MOTOR and TRAIN DRIVES on the AutoStar? If not, do them. For more information on non-PE model alignments (ie, non-Auto Align) see the Helpful Information: AutoStar Info page. For more information on the PE models (with LNT) see the "Premier Edition / LNT Specific Tips" section on the Helpful Information: Telescope Tech Tips page. Keep in mind that the HOME positions for Auto Align and non-Auto Align modes are different.
Subject:	Can I use a big diameter eyepiece in ETX-125PE?
Sent:	Friday, April 25, 2008 18:00:18
From:	Mike Shneyder (
I am just learning my first steps with the ETX and I am already facing a
problem. Recently I purchased a Baader Hyperion 17 mm eyepiece to
compliment the 26 mm Meade that came with the scope. But Hyperion has a
2" diameter body just above a 1.25" barrel and this body interferes with
plastic red-dot finder bracket, which is installed on top of the rear
cell. The Meade 26 mm is a small diameter eyepiece and it does not have
this problem. I also believe that previous versions of ETX-125 did not
have this problem as well since they did not have this style finder

Can you advice me what to do? Hyperion is a nice EP and I would like to
keep it. Plus I would like to get a 1.25" to 2" adapter for 2" eyepieces
and it is even bigger than Hyperion. The eyepiece diameter is too big or
EP holder tube is not long enough. I can cut a relief in the finder
bracket, but I would rather not. It is already flimsy enough.

Do you know how the eyepiece tube is installed in the rear plastic cell?
Is it threaded or glued? Maybe I can replace with a longer one. If I
could make it 10 mm longer, it would be a solution. I own a lathe and
can do my own work.

I hope there is a simple solution. Other people may already asked you
the same question, I just could not find anything related on your
Thank you in advance for any help.
Mike Shneyder
Mike here: You could use the eyepiece at the rear port. You would need a Visual Back to attach the eyepiece. See the Accessory Reviews: Showcase Products page for one example. You can get a 1.25" to 2" adapter; there is one discussed on the Accessory Reviews: Eyepieces page.


Thanks for your response. But I would still like to know how to replace
the eyepiece tube. Do you know?

Mike here: Well, you could replace the eyepiece holder but that would require a lot of modification. You would have to cut the telescope to accommodate a larger opening. And then you would have to mount the 2" eyepiece holder by drilling additional holes in the telescope tube. To do all this safely you would want to remove all the optical components from the tube. And once you get the 2" eyepiece holder attached you would then have to put all the optics back in and recollimate the optics, something that is not easy with the ETX models unless you have an "optical bench" or are prepared to spend a lot of time adjusting the optics.


I am sorry for not making myself clear. I do not want to install 2" port
directly in the plastic cell. All I need is to make the eyepiece holder
a little longer to eliminate interference with finder bracket. Yesterday
I posted the same question on So far there is no
answer. Here is a picture of my setup.


Mike here: The simplest might be to use a Barlow Lens with the lens removed. You may or may not be able to focus however. A "Shorty" style Barlow Lens would be safest and is the model best used (with the lens) on the ETX models. If that doesn't work, I'd still go for using a Visual Back on the rear port. Of course, you could have some balance issues depending on how heavy the eyepiece is.


Thanks, Mike. I have an idea how to make a short extension of the tube
in case I am not able to replace the tube with a longer one.

Mike Shneyder
Mike here: See the solution in the article "Eyepiece Extension" on the Helpful Information: Telescope Tech Tips page.


Thank you for your help, Mike. I already know that Agena and Scopetronix
offer 1" long EP barrel extensions. Agena also offers 23 mm extension
with a brass compression ring for the scope's EP tube. The latter one is
quite good, I just not sure if it will hold an EP with a barrel groove
like Hyperion.
Mike here: I would avoid Scopetronix. See the Editorial Page on my ETX Site.
Subject:	parts
Sent:	Friday, April 25, 2008 12:28:53
From: (
wondering if you have a source for eyepiece thumb screws & viewfinder
alignment screws for ETX-125EC Thank You  Dan.
Mike here: First, try Meade. If they won't send you the screws try ScopeStuff (link on the Astronomy Links page).


Found what I need at SopeStuff  Thanks Dan

Subject:	Scopetronix
Sent:	Friday, April 25, 2008 05:24:53
From:	Alex Frade (
I wish I would have read your editorial of Scopetronix prior to placing
an order from them on 4/11/08. I went to their website and ordered a
Flexi Focus, a dew shield, and an accessory tray all for my newly
purchased ETX 125. I received an electronic e-mail ackowledging my order
which I paid by credit card. To this day I have not received my order
and my numerous e-mails to their contact information have gone without
one single response.

There's no telephone of address on the website and finally after
researching on the internet I found a telephone number, that after
numerous rings goes to a message that tells you that the memory is full.

By know I have given up that I'll ever receive my order and suspect that
they might not even be in business. I am in the process of contacting my
credit card company to dispute the charge.

However their website is fully operational and I wanted to warn others
not to order from them.
Clear Skies,
Alex Frade

Subject:	Feeding images from the EXT PE 125 to a Laptop
Sent:	Wednesday, April 23, 2008 13:53:31
From:	Phil Gayle (
I've just bought the 6.0 version of Starry Night Pro and with all the
great utilities I've been wondering if it's possible to connect a video
feed to the scope and view images on the laptop in real-time? If
possible how would I go about it?
Thank You
Philip Gayle
Mike here: You would attach a video camera of some sort (electronic eyepiece or webcam) in place of an eyepiece. You would then run the video output to the appropriate software on your computer. However, keep in mind that "real-time" video may not be very useful except on brighter objects like the Moon. Also, you will need to be at the telescope to align it.
Subject:	GPS ETX125PE 497
Sent:	Wednesday, April 23, 2008 08:55:55
From:	Eckert, Dennis (
I've been reading thru the various posts on hooking up a GPS to my ETX,
but I haven't been able to find an answer to what I think is a simple
question.  I'm pretty sure my Garmin 95AVD (older aviation version)
outputs the $GPRMC string.  I haven't built the RJ-11 to DB-9 cable yet
to the GPS.  I do have a connection to one AUX port to my laptop for
running AutoStar Suite and AstroPlanner.  I'm not interested at this
point in buying the StarPatch solution if I don't have to.  So, will the
497 read that string without me having to purchase any vendor solution
like StarPatch? My 497 has Dick Seymour's latest patch applied.  I
turned off the GPS StarPatch read capability in the patch because I'm
under the impression that I would have to buy the StarPatch package for
the 497 to accept the GPS data.
Dennis Eckert
Everett, WA
Mike here: I'll let Dick respond:
From:	Richard Seymour (
>> I've been reading thru the various posts on hooking up a GPS to my  
>> ETX, but I haven't been able to find an answer to what I think is a  
>> simple question.  I'm pretty sure my Garmin 95AVD (older aviation  
>> version) outputs the $GPRMC string.  I haven't built the RJ-11 to  
>> DB-9 cable yet to the GPS.  I do have a connection to one AUX port  
>> to my laptop for running AutoStar Suite and AstroPlanner.

You are -not- connected to an AUX port, you are connected to
the serial port on the 497 Autostar itself (i sure hope).
The AUX ports are **not** rs232 serial ports, and damage
can be done to both PC and Autostar if you attempt to hook them up
like that.
(i have to write the above since other folks might -try- an 
incorrect AUX hookup)

>>  I'm not  
>> interested at this point in buying the StarPatch solution if I don't  
>> have to.  So, will the 497 read that string without me having to  
>> purchase any vendor solution like StarPatch? My 497 has Dick  
>> Seymour's latest patch applied.  I turned off the GPS StarPatch read  
>> capability in the patch because I'm under the impression that I  
>> would have to buy the StarPatch package for the 497 to accept the  
>> GPS data.

If you do not patch the Autostar to do so, it will not natively
understand GPS "sentences" arriving at the serial port.

If you turn -on- the GPS patch in StarPatch, it will load the "demo"
version of Chris Carson's (Mr. StarGPS) firmware.  It -will- be
able to understand the GPS message, and will display it on the screen
soon after power-up.


It won't -set- the data into the Autostar.

If you pay $79 for StarPatch, then the GPS data -will- get set when available.
(and future firmware downloads/updates will take only two minutes, max).

have fun

Subject:	Re: Need some help getting a 125 to work;  can you help
Sent:	Monday, April 21, 2008 22:52:03
From:	Michael (
I have the EC model.   There is the controller for focusing.  I thought
when it was plugged in it would focus.  I thought it was internal.  It
sounds as if I don't know the machine properly.  I took the manual
control knob out of the bottom of the box.  The spring and shaft were in
the OTA and the rear cell assembly was loose and flopping around inside
the OTA.  I put it back together and I now can focus with the control
knob.  I would bet a lot of money the scope is not collimated correctly.
What else needs to be done to insure it is inserted correctly.  It
appears that there is only one way for the rear cell assembly to put
installed.  I do not know how to collimate the scope yet.

I assume the electric focuser is on the outside of the scope.  I'll go
back and look at the different models and see what they should look

I don't want to spend the money of a supercharge just yet.  If I read
enough I may be able to do that myself.  Certainly not to his standards
but we'll see.

Do you have any suggestions?

And again thanks for your help and time.

Mike here: There is a battery operated handcontroller (the user-installable battery goes in the handcontroller) for the Meade electric focuser. There is a separate handcontroller for the ETX (standard handbox that came with the ETX EC models or and AutoStar). The AutoStar will control the focuser if the focuser cable is connected. Perhaps this article will help: As to a "star test" for collimation and doing a collimation yourself, see the Helpful Information: Telescope Tech Tips page. However, be aware that doing the collimation yourself, while not impossible with ETX Maksutov-Cassegrain models, is difficult and you can make things worse instead of better.
Subject:	My alignment issue
Sent:	Monday, April 21, 2008 17:29:11
From:	Steven M. Wyatt (
I think I may have it worked out.
I have adjusted the Time Zone to -4 UT (because that is where I am) at
the suggestion of someone else, and turned off Day Light Savings.

Just did an alignment ('cause it is now dark). The scope is not dead on
as I would like, but pretty darn close.

I wanted to thank you all for you suggestions. I great to know that
there is some good support out there.

Thanks again (vielen dank..tusen takk)

Of course I am open to any additional suggestions too!

Subject:	ETX-125 - problem with alt motor
Sent:	Monday, April 21, 2008 06:24:28
From:	Finn Stokes (
I am emailing you from South Australia.
We have just purchased an ETX-125 (picked it up today) and are having
problems with initial allignment -

We kept getting error messages during the sequence ('motor drive

We then tried calibrating the motors after resetting the scope also with
no success.

It seems that our scope works in three directions - both sideways
directions and downwards but not upwards. Bofore the reset, when we
tried to move the scope upwards from the autostar hand controller it
made a quiet internal noise but wouldn't move. It now makes no sound at
all and still won't move.

Is it worth us attempting to fix the problem or should we (a) try to
contact Meade or (b) return to scope to the suppliers?
Finn Stokes
Mike here: Could you be overtightening the axis lock? If not, then try reversing the AutoStar cable.


The axis lock is as loose as we can make it without the scope tipping
forward. We reversed the cable and it began to turn downwards both when
it was supposed to turn down and when it was supposed to turn up. We
turned the scope off and on again and this time the autostar seemed to
lose all power when the telescope attempted to turn up. We again turned
it off and on again and this time it started to turn up but smoke
started coming out of the base and possibly right arm (or it could have
just looked that way as the smoke from the base coiled past) of the
telescope so we quickly switched it off... not sure where to go from
Mike here: Smoke? Was the cable inserted correctly (pin orientation)? Were you using the internal batteries or an external power source? At any rate, smoke is obviously not a good sign and could be a sign that there was a failure pending and that was causing the problem. At any rate, assuming you didn't cause the short by using an improper power connection, you should contact the dealer for an exchange.


We were using the internal batteries and the cable seemed to be plugged
in properly. Interestingly, the smoke happened when the telescope seemed
to be functioning properly. even after the smoke started it was still
turning up until we noticed it and turned it off.
Mike here: It was likely an intermittent connection someplace inside. I still recommend contacting the dealer.


Thanks for your help Mike.
We will return it to the dealer - I'm not game touching anything else as
I will start to worry about warranty...

Subject:	125 EC Horizontal lock limit stop question
Sent:	Saturday, April 19, 2008 02:05:18
From:	Julian Plant (
Greetings from a newbie in Surrey UK!
I have just acquired a 125 EC which has not been used for five years.

Previous owner no help on the matter, no warranty etc heyho.

The horizontal travel is approx. 340 degrees before hitting a solid stop
in either direction i.e. it will not perforn a single 360 degree
rotation and I understand from other postings that it should do more
than this.

It is not possible to perfom a full 'goto' without graunching and me
hitting abort, I feel that this is probably not right!! The stops are
very solid and absolute.

Having said that, everyting else performs as it should, first light I
saw Saturn and was over the Moon, hmm, I need to rephrase that but you
know what I mean :o)

Any thoughts or suggestions gratefully received, many thanks in advance,
best regards,
Mike here: There is likely some obstruction in the base that is preventing full movement from hard stop to hard stop (normally a rotation of slightly less than twice around). The typical sources of the problem are: wiring (use caution when rotating the telescope as you could cut the wire), debris, or a broken hard stop that has shifted. You would have to open up the base to check.


Thanks for your swift response Mike, you have confirmed my suspicions,
the good thing is that the electrical functions are operational so the
wiring sounds ok. A job for the morrow then, will let you know how it
Many thanks again,
Mike here: The wiring could still be intact but damaged. Be certain to check it.


Just had to laugh, removed the plastic base and then realised that I
hadn't a clue what to do next, I guess the screws that can be seen at
intervals when the base is rotated have to come out.

Anyway, spotted an aluminium post that I guess is the end stop, that is
intact. Without removing the whole assembly I can go no further and
don't want to mess the whole thing up!

Base back on, needs a bit of thought.

all the best, Julian
Mike here: There are a couple of "hard stop" articles on the Helpful Information: Telescope Tech Tips page.
Subject:	Need some help getting a 125 to work;  can you help
Sent:	Thursday, April 17, 2008 20:14:09
From:	Michael (
I got a 125 supposedly new never used.  But when I got it I could see
thru it, there were two noises inside the OTA of something loose, the
controller kept reinitializing, the electronic focuser would slew but
not focus, and the scope arrived with the horizontal lock lever and the
manual focus knob were in the bottom of the box.  I was not able to put
the manual focus knob on because the shaft was not in the hole.  I put
the lever back on its nut and I can basically lock it down.

I took it apart and found the rear cell assembly off and it was flopping
around inside along with the spring and shaft.  I cleaned everything and
replaced everything where it belongs.  Now I can look thru the scope
again and get an image.  It is out of focus and I cannot focus
electronically or manually.  The manual focus knob just keeps rotating
without apparent movement of the mirrors focal point.  The electronic
focuser creates no noise when pressed appropriately.  I can get the
scope to slew.  I have not tried to track as I can't focus.

I'm still trying to figure out how to get to the polar alignment part
with the 497 but that's just I haven't looked hard enough.

What do I do?  The seller is talking to me and I'm to call Meade
tomorrow and discuss fixing it or sending it in for repair and get an
estimate.  Can I fix it?  Did I do something wrong or overlook

I appreciate all your help so far and I don't know quite honestly how
you do it.
Thanks again.
Mike here: Wow! It sounds like it was in bad shape. Hope you didn't spend too much money on it. It sounds like the focus shift is disconnected. See the article "Focus Shaft Fix" on the Helpful Information: Telescope Tech Tips page if you want to attempt to fix it. As to alignment steps, there are many tips on the Helpful Information: AutoStar Info page. If you didn't get a manual you can download for your telescope at Meade's site (see the FAQ page on the ETX Site for a link to the manuals).


The focus shaft does work.  I guess I was too tired to see it last nite.
But the electronic controller for the focus does not.  I can use it to
track and slew but it will not focus.

Any ideas?

Mike here: Do you mean the focus motor runs but the focus shaft doesn't move or that the motor doesn't run?


I don't hear anything running when I press on the in or out button on
the electronic focuser, Mike.
Mike here: So you are using the focuser handcontroller and not the AutoStar for focusing. Have you checked the battery? You might try using the AutoStar to control the focuser (assuming it is the Meade Electronic Focuser for the ETX).


Yes, I'm using the manual focus control knob but I'm still having
problems focusing.  I can go from one stop to the other with the manual
focus control knob and not be able to focus far away.  I can focus
nearby objects though. Which buttons work on the 497 to control focus?  
I used the electronic focuser again tonite and it continues to slew.  
I don't know how to track with it yet.  But I cannot get it to focus.


PS:  You've got to be incredibly busy.  I thank you for your time.
Mike here: Now you have me confused. The Meade focuser replaces the manual control knob. Since you say you are using the manual focus knob lets address that focusing problem. If you can focus near objects but not objects in the sky then it sounds like the mirror (which is the moving part for focusing) is not positioned correctly. You would have to disassemble the rear cell to properly position. Then you would have to recollimate the telescope (not an easy task). At this point you may want to consider contacting Meade, or perhaps Dr Clay Sherrod for his "Supercharge" Tune-up Service.
Subject:	RE: ETX 125 AT Alignment Issue
Sent:	Thursday, April 17, 2008 18:17:53
From:	Steven M. Wyatt (
Sorry to say Mike,
Nothing worked.

Calibrated Motors, then re-trained. All after a reset.

I used a torpedo level to make sure everything was level.
Tripod, and even used the level to ensure the fork was centered over the
control panel for home position, by using the small triangle by the DEC
knob as that appears to be the center, and the red LED on the control
panel appears to be the center.

Then pointed True North using a compass.

Alignment stars were WAY off. Worse than before.

Then re-aligned the scope by pointing to Polaris. Was closer, but GOTO
just wouldn't GOTO.

Same issues as before. Even my alignment stars wouldn't be close in
GOTO. Saturn wasn't even in view, and other targets were just way off.

I'm suspecting an issue with the scope, which is disappointing given
that it's not that old. And knowing Meade, it may be weeks if not months
to get it repaired under warranty. :(

I really like the scope. My daughter, neighbors kids and I have a great
time with it. Just sad to think that after so little use (due to winter)
that it's not working properly.
Mike here: Did you correct for your local Magnetic Variation when using the magnetic compass? One other thing you can easily try: reverse the AutoStar cable.


Not sure what you mean by " local Magnetic Variation".

When you mean reverse the AutoStar Cable, do you mean the hand
controller? And take then end in the controller and put that in the
control pad on the scope and the other end in the hand controller?

I don't recall ever changing it around, but if that's what you mean.
I'll try that.

Hey, I didn't expect an answer right away. You must be very dedicated to
the ETX crowd.

I really appreciate any help. I'm just hoping it's just me and not the

Everything seemed fine when I got it in October. Then it pretty much sat
for the winter since it was too cold (for me at least).

It was suggested by a member of Meade4M to check the Time Zone, which
appears to be correct according to NASA. -5 UT for Eastern.
Mike here: Depending on your location, True North and Magnetic North can vary up to about 20 degrees. To calculate Magnetic Variation (also known as Magnetic Declination) for your location use one of the sites on the Astronomy Links page.


Thank you again Mike,
I'll try this tonight. Looks like I'm off by 14 + degrees here.
I can see how that could make a difference.

Cross your fingers! :)


I have had my scope connected to my computer using the Meade Software,
for imaging. Do you suppose that may have messed things up? Unlikely,
but you never know. 1 person said this messed his up. And another even
suggested reloading the AutoStar software.
Mike here: The software controls the telescope AFTER you have done the alignment. But reloading the ROM can help resolve some issues. If you do that I recommend doing a CALIBRATE MOTOR and TRAIN DRIVES following the update.
Subject:	ETX 125 AT Alignment Issue
Sent:	Thursday, April 17, 2008 10:34:46
From:	Steven M. Wyatt (
First Off.what a great site. I find myself getting lost in there
sometimes. J

I'm hoping you, or someone, may help me out.

I purchased my ETX 125 last October. It was from Meade's Outlet store,
and for the most part, is a great scope.

But the last several nights, (since the weather has finally cleared and
is getting more comfortable for viewing here in New England), I've been
having trouble getting a half way decent alignment.

Unless I'm aiming at the wrong star (Polaris), I don't know what's

This is what I have done (last night).
Now I have tried these steps several times making changes to settings:
a) Location - by zip code and then by closest city
b) Time - both with and without Day Light Savings set

1) Reset Scope
2) Re-Trained Drives
3) Set in home position
4) Leveled scope and aimed at Polaris
5) Easy Align (2 stars - Capella and Sirius)
6) AutoStar said alignment was successful

Now, when I try goto I'm like no where close to a target.
Saturn is always too high and to the left (looking through Finder
Scope), then eyepiece.
Orion, Mars, my alignment stars and even Polaris always seem to be low
and to the left.

Now, if AutoStar says my alignment was successful...why am I always
consistently off?
I'm contemplating getting a reticle eye piece to aid in the training (to
be more precise) and in the alignment process (to be dead on center),
but I would think that I would at least be in the right "neighborhood"
of the targets after the alignment.

I know it's not a battery issue as I use the Power Supply.
The knobs are secure, so I don't see that there would be any movement
there. Any suggestions?

Thanks Mike. Any suggestion is greatly appreciated. I've read so many
websites and tried so many things, I beginning to think there may be an
issue with the scope itself.
Mike here: You didn't say you did a CALIBRATE MOTOR. You should do that. Also, you said you were aiming the telescope at Polaris. Is the telescope mounted in Polar Mode or Alt/Az? Since you said you were aiming the telescope at Polaris I'll assume you have in Polar Mode. Have you set the AutoStar for Polar Mode?


No, I have the scope in Alt/Az.

You know, last night prior to training I did forget to calibrate first.
You do that first, right? Else it just throws the training off. I did
calibrate the other day in my trials as well, but that didn't have much

Is there a proper way of calibrating? The way I did it the other I just
hit the button, the scope moved left/right and up/down. That was is.
Should it too be in the home position, or does It not matter. Perhaps
I'll try that again.

Oh, and thanks for such a quick reply.
Mike here: It really doesn't matter where the telescope is when doing the CALIBRATE MOTOR. It just measures the encoders output. However, it should be done whenever swapping power sources or after a recharge if using external battery or when the power gets low. With the telescope in Alt/Az you point the telescope towards True North and not AT Polaris. For more on alignments, see the Helpful Information: AutoStar Info page.


Thanks Mike,
I'll give this all a shot again tonight and let you know how I make out.

Subject:	PE 125 and Eyepieces
Sent:	Wednesday, April 16, 2008 19:57:45
From:	Brian Everheart (
so glad i found your website.  i have had the PE 125 now for around 2
weeks and want to make sure i am using it correctly.

i think i had a mistake in judgement when i trusted a guy at a scope
shop on what the most powerful eyepiece i can use with the scope is.  he
told me a 9.5mm was.....sold me an epic ED.....after further research,
it appears the max practical magnificaiton is 500x which means i can go
a lot more powerful.

question is, what is the most powerful eyepiece i can use with the ETX
125pe is....i recently purchased the #126 barlow but dont have it yet...

what brand of eyepiece do you recommend?  what is the most powerful one
you would recommend with this scope?  with a 9.5mm and no barlow, is not
normal to view saturn, and barely be able to see the rings?   Live in a
community north of dallas, on the NW corner of lake lewisville...there
is light polution in the area....

Thanks, and i look forward to your response!
Brian Everheart
Little Elm, TX
Mike here: Keep in mind there is a theoretical maximum magnification for any telescope based on its aperture. See the FAQ page for info on how to calculate that magnification as well as how to calculate magnifications for any eyepiece with your telescope. Whether or not you can effectively use that max magnification depends on the object being viewed, the viewing conditions, whether or not the telescope has reached "thermal equilibrium", and the condition and quality of all the optics used (telescope, eyepiece, Barlow Lens). Bottom line: don't expect to use 500X for the ETX-125. As to eyepieces, see the Accessory Reviews: Eyepieces page as well as the Helpful Information: Buyer/New User Tips page.


Thanks for the quick response.  Would you consider the Epic ED and
Expanse to be quality eyepieces?  I like that they have big exits....
Mike here: I have no experience with them but if you search the Site for "Epic eyepiece" you will find some comments.
Subject:	Autostar and USB and StarPatch
Sent:	Wednesday, April 16, 2008 18:40:24
From:	Patty & Doug (
I've gleaned much info from your site and appreciate it very much.  The
most recent was today when updating Autostar for my new etx125 using a
USB-to-Serial adapter (Belkin-F5U409).  As you probably have already
guessed CRASH!

Searching your site I saw the suggestion to try StarPatch (Richard
Seymour, April 2006) and your question, after that suggestion, wondering
if it was more tolerant.  It seems to be, at least with the mine.  First
time it worked without a problem and it is fast!.

I cannot thank you enough for all the help you, Richard & Dr. Clay have
given my wife and I since we bought out Etx90EC back in the late 90's. 
Sorry it has taken me 10 years to say thanks!

Doug McConnaughay
Waxahachie, TX

Subject:	A comment in re John Watson's e-mail on your feedback page.
Sent:	Wednesday, April 16, 2008 14:28:30
From:	PHIL G (
In reference to John Watson's post:
Your reply (in part):
"Alternatively, if you do not need to move the telescope, you could
align it the night before and use the SLEEP or PARK functions in the
AutoStar. " There is a simple trick to relocating the telescope after
aligning it and then bringing it inside for the night. I have my
"favorite" spot in my driveway marked with three shallow holes drilled
with a masonry bit (concrete drive, not Macadam as the Brits call
Asphalt). The legs of the tripod fit in them and if one were to
carefully pick up the whole rig and then bring it back another day your
original alignment should be *very* close. I have this set to a fairly
good Polar alignment orientation (not drift) and it makes my setup go
MUCH quicker!

Helps to set up for Solar observing as well.

In a wood deck one could simply drive three small nails in to mark the
leg position. On a grass surface one could perhaps drive three pieces of
plastic pipe in for the legs to fit in. Of course using vibration pads
may complicate this...
Phil G

Subject:	Re: The fine work you did on my ETX-125
Sent:	Wednesday, April 16, 2008 08:51:04
From:	P. Clay Sherrod (
Wonderful report and thanks so much for taking the time to write.
And you are most welcome!

Dr. Clay
Arkansas Sky Observatories
Harvard MPC/ H43 (Conway)
Harvard MPC/ H41 (Petit Jean Mountain)
Harvard MPC/ H45 (Petit Jean Mtn. South)

----- Original Message ----- 
From: Mark
> Hi Dr. Clay,
> Thank you, Thank you, Thank you...?? Did I say Thank you?
> I was able to take my scope out last night. Michigan weather has not been that good 
> this winter.? I had a blast.? I went through almost all of the Meade guided tour and 
> the Urban tour you loaded for me.? Every go-to was dead on.? I did the 2 star 
> alignment only once and observed till my fingers were stiff as a board. I love your 
> Urban tour. It was a pleasure to observe something different than what I usually hunt 
> for.
> I can't wait till I take it to the Cherry Springs Starfest this May and get under some 
> nice sky's and observe the other tours you set up for me.
> One last Thank You...
> Respectfully
> Mark

Subject:	ETX-60 or 114EQ-ASTR?
Sent:	Tuesday, April 15, 2008 20:15:17
From:	Dave Murphy (
I recently purchased an ETX-125PE for myself and my Dad loves it.  I
want to get him a decent scope however the 125 is wayyyy too much scope
for his desire to look at the Moon, Mars, Jupiter, etc.  I just found on the ETX-60 Backpack edition with the tripod,
backpack, 3 eyepieces, and built in Barlow for $99, or with my coupon
and club membership it's only $79.  I also noticed they have the
EQ-114ASTR for about 40 bucks more.  Which would be your suggestion for
the price?  Obviously the 114 has a much larger objective, however I was
thinking something more portable and easier for my Dad (who's up there
in years) to setup and use would be more beneficial.  Is the ETX-60 a
steal for $79 or should I go for the gold?  Thank you, sir, for your
help!  - Dave
Mike here: The ETX-60 (you sure it is the ETX-60 or is it an ETX-80, which is the only model that I know that includes the built-in Barlow Lens) can be a disappointment to some users due to the short focal length and small aperture. Your dad might prefer the larger aperture of the 114EQ-ASTR. On the other hand, the ETX has the AutoStar GOTO controller and will track objects in the sky automatically. The 114EQ-ASTR only has manual tracking (I think). For more on how well the ETX refractors models perform see the Helpful Information: Buyer/New User Tips page for my ETX-70 comments as well the Helpful Information: User Observations page for other users comments.
Subject:	re: How best to drive my ETX-90EC from my iMac -- 50 feet away?
Sent:	Sunday, April 13, 2008 17:15:54
From:	richard seymour (
For simply -controlling- the telescope, put the Keyspan USB-to-serial
adapter at your MAcintosh, and simply run the -serial- line the 50 feet.
You can use telephone extension cords for the "cable", or make your
own.  At the telescope end it needs to be a "handset"-sized connector.

For that matter, OPT sells 25 foot and 50 foot "Meade 505-like" cables
which will handle the length and connectors for you.

RS232 serial lines and signal level are excellent and designed for long runs.
USB is -not- designed as a long-run protocol.

Unplug everything at *both* ends if you are expecting nearby thunderstorms.

have fun

Subject:	ETX Sites...
Sent:	Sunday, April 13, 2008 09:52:11
From:	Chris Harvey (
I'm Chris Harvey and I participate in the ETX news group, you will
probably have seen me post occasionally. Just wondering if I would
qualify for a link from your ETX links page? I've got a link to you in
my resources of course.
This is my ETX page:
Then I have my Nikon D50 night sky page separately here:
The reason being that I wanted to show what somebody can do with a DSLR
on its own, then separately what I've done with my ETX-105 including
using the DSLR. So, it's the ETX page I thought you may like to link to.
I recognise many of the websites you have listed there.

Out of interest, are you keeping a log of which Messier's you have seen?
I'm now up to about two thirds of them with 36 to go, I have a journal
of this offline, soon to be online, and I've only had a scope for two
years. I think I'm going to start a page for the Caldwell catalogue as
well. Just wondering if you had managed to see all the Messiers in your
years of experience? Maybe you have even attempted or completed a
Messier marathon?!
Cheers and clear skies,
Mike here: I do keep a log book but haven't tracked how many of the Messier objects I've seen. Over the decades I've seen quite a few but I know I've not (yet) seen the all.
Subject:	ETX Solar tracking
Sent:	Saturday, April 12, 2008 03:11:53
From:	John Watson (
I bought an ETX125PE, which I'm delighted with - the optics are superb
and the Autostar (which I've never used before) seems both accurate and

However, I want to use the scope for solar observing with a
full-aperture filter and I can't quite figure how to set it up to track
(ideally alt-az, but it doesn't really matter) well enough for visual
observing, when the Sun's out and I can't see any alignment stars!
So naturally I'm turning to the ETX guru...
Thanks and best regards
Mike here: Solar tracking for visual purposes usually works fine at sidereal rate. Generally no need to set a specific tracking rate for the Sun. As to aligning, the simplest way is to use Auto Align and assume that the alignment stars are centered. This will work in Alt/Az or Polar. Alternatively, if you mount the ETX in polar mode you can just power on and set the Targets to Astronomical on the AutoStar. That will start the RA drive immediately with no need to align. Either way, then slew the ETX using the AutoStar to the Sun (with the filter installed). I use the shadow of the ETX to get it pointed at the Sun but there are some "sun finders" on the Helpful Information: Telescope Tech Tips page (look for both "sun" and "solar").


Thanks for a very fast response.  You know, it just hadn't occurred to
me to assume that the alignment stars were centered'...   I use the
'smallest shadow' method for aiming my ETX90RA at the Sun, which is easy
to do.
All the best
Mike here: The better the ETX Home Position the better the "fake" alignment will be. Alternatively, if you do not need to move the telescope, you could align it the night before and use the SLEEP or PARK functions in the AutoStar.


1.  Good point.
2.  In England it rains unpredictably  -  as they say, "no climate, just
weather" !

Subject:	How best to drive my ETX-90EC from my iMac -- 50 feet away?
Sent:	Friday, April 11, 2008 12:38:41
From:	James Haight (
I'm a novice ETX-90EC operator.  I've had the scope for about 10 years,
but am just getting around to using it.  I'm researching methods to
remotely control the ETX-90 from my stationary iMac Intel Core 2 Duo
using ScopeDriver X.  For a good view of the sky, the scope must be
about 50 feet from the computer.  A Sabrent USB-RJXT extender adapter
with 50 feet of Cat5e or Cat6 cable, connected to the scope via the
Keyspan adapter, looks to be a solution.  The possible rub: the rig will
not support USB 2.0; it will drop to 1.1.  I'll greatly appreciate any
thoughts on the issue.
Regards, Jim Haight
Mike here: You need a RS-232 cable run to control the AutoStar, which controls the telescope. So, the USB for control will be at the computer. But you would need a USB-serial adapter. I use a Keyspan one on my Macs and it works fine. This connection would only allow you to control the telescope, not see what it is seeing. So you would then have to add some sort of camera to the telescope. You could use a Firewire camera, a USB camera, or an "electronic eyepiece" which connects to a TV or monitor. An alternative solution would be to have a laptop computer (or other small or inexpensive) computer at the telescope and then control that from the iMac. If you use Mac OS X 10.5 you can use Screen Sharing. If you don't use Leopard you can still share a screen using VNC server and client software (both available in free versions).


Yes, I have the Keyspan adapter and have tested it using an additional
12 feet of USB cable.  Works perfectly.  Now, as to adding some sort of
camera to the telescope, I thought I'd try another person at the
eyepiece first.  But now you have me chasing the various cameras you
suggest!  Thanks again.  Jim Haight

Subject:	What happened to Scoptronics?
Sent:	Friday, April 11, 2008 12:43:05
From:	plechaty (
I understand they went out of business.  Did any other company or
individual pick up their inventory and or line of products?  I am
interested in a DSLR Maxiview for a D70s Nikon camera.
Thank you
Bill Plechaty
Mike here: See the Other: Editorial Page on my ETX Site for some comments.
Mike here: Got an iPhone? Want to display UTC on the iPhone's World Clock? This is a great tip for astronomers!
Subject:	ETX PE - External 12v connector polarity
Sent:	Tuesday, April 8, 2008 23:49:39
From:	Andy Chiu (
I want to make a recharge battery box to supply battery power thru the
12V external connector.  Please advise the center pole is (+) or (-) in
order to connect it with correct polarity.
Best regards
Andy Chiu
Mike here: Your answer is on the FAQ page on the ETX Site.
Subject:	Accident with my new ETX 125 PE telescope
Sent:	Monday, April 7, 2008 13:32:21
From:	Mr Clive Musselwhite (
I have just made a stupid mistake with my ETX 125 telescope - I have a
variable transformer which I have to switch to the 12 volt setting but I
forgot and let it align on the 15 volts my scanner uses. At first it
started aligning fine but then the Autostar started fading out, on and
off, but not quite going off and the telescope suddenly went up to its
extreme. I switched it off immediately and realised what I had done -
sure enough, I hadn't switched it back to 12 volts!

On restarting with the correct voltage the telescope seemed to be
working ok but it hung on alignment north and I realised that the left
arrow on the Autostar will not turn the telescope. There is also that
hot electric motor smell coming from the drive chamber. Although the
telescope is under guarantee I wouldn't send it back for something that
I have caused, that would be dishonest. I have decided to wait until it
has cooled down and try again tomorrow but I think I have probably
burned out the left motor (I assume it a different motor for each
direction which is why the right one works).

I would be grateful to you again Mike if you could give your advice on
this - silly I know - should have put a sticker somewhere to remind me
as I've nearly done this before. Haven't used it for about a month due
to cloud and cold but took advantage of a clear sky tonight (wish I


Mike here: If you smelled something burning then you likely either fried a motor or some circuitry component. You could open up the base and see if you see anything burnt. You will likely have to return it to Meade for a repair.
Subject:	Re: Aligning Without Polaris
Sent:	Friday, April 4, 2008 20:56:40
From:	Steve Hollar (
Mike, I just had to let you know, I went out tonight and experimented
with the "Drift Method". I was absolutely blown away. The learning curve
was easy once I matched what I was seeing with what I was reading. I
didn't have the computer or camera connected. This was just a testing

I used the good ol' Orion Nebula for my object. The nebula itself looked
like it hadn't moved in about fifteen minutes. More important was a star
right on the edge of the field of view. It sat right there. I was truly
amazed. Thanks for turning me on to this. Hopefully I'll be taking some
photos this weekend.

Steve Hollar

Subject:	astronomy of the moon
Sent:	Friday, April 4, 2008 06:35:25
From:	Andres Hebberecht (
I searched in all your newsletters,Mike's biografy,just for fun etc to
find an answer to the following questions,which I guess they must be
answred somewhere in your extensive letters....but I can't find it.

what is the name of he boulder which lies on the moon's surface,roughly
at 61 km south of mons pico and 32 km west of pico E ?

I see a white dotted line ,some 170 km long from the end of vallis alpes
to that boulder.It is difficult to see. Am I right or is it just
imagination ?

looking at your theft page I see your stolen "observing chair" which I
would like to have one but I don't find it at starbound's nor at
shop-it.where could I get this item and so stop my backpain at
once.Thank you for your answer which is this time somewhat different and
has nothing to do with scope  problems. andres
Mike here: I recommend getting a Moon atlas or chart to help you identify objects on the Moon. They don't identify "boulders" however. There are also software programs that can provide charts. As to the Starbound Observing Chair, I recently got the replacement at OPT ( so they have them.


Thank you for your help,I'll start with  the virtual atlas of the moon
and will get in  touch with OPT.I'll see first if they are alsoo in
spain....thank you. andres.

Subject:	re: MySky  - Theory of Operation? (was MyStar)
Sent:	Thursday, April 3, 2008 21:55:57
From:	richard seymour (
You asked:
> how does it "know" the altitude and azimuth of the direction it's pointed?

...and your email address is "ieee", so i'll assume some level of electronic background.

If one looks at how Meade's Level North Technology (LNT)  module works,
it probably hints strongly at the technology in the MySky.

They use a magnetometer coil to accuately sense "north", and the MySky probably
improves on that by using a Hall effect compass for the other angles.

For the tips and tilts, the LNT module uses a dual-axis accelerometer chip
to detect the direction of the local gravity vector.
The MySky might use more than one to "average out" noise, or to provide
coverage of difficult angles (such as the circuit board tilted straight up).

The chip used in the LNT module is a MXD2020E from MemSic.

The chip uses a rising column of hot air as its "plumb bob".
A hot wire heats the air, and it rises between a balanced
thermocouple bridge.  If the device is tilted, some of the
thermocouples get warmer than the others.
Unfortunately this device is -also- sensitive to lateral
acceleration (shakey hands?) so slow motions (or giving the
MySky time to average out the "noise") are required.

I don't -know- that the MySky uses those chips, but
they'd certainly be in the running...

have fun

Subject:	Stuck Dust Cap on ETX-125 PE
Sent:	Thursday, April 3, 2008 18:44:52
From:	dan colesworthy (
I've been enjoying your site for several months and finally got up my
courage and ordered one of the astro tube ETX-125 PEs from Astronomics. 
The shipment arrived here in Boulder, CO. in 3 days, and looked
completely undamaged.

I've been trying to assemble the scope, and can't get the darned dust
cap off the scope!  I must be doing something stupid!  Unscrewing starts
to remove the entire end of scope/lense assembly so that can't be it. 
It looks as though it ought to just pop off!  So far I can't budge it. 
Any advice before I damage the scope or give up and try to return it?

Thanks in advance,

Dan Colesworthy
Mike here: See the item "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 FAQ page.
Subject:	Tripod
Sent:	Thursday, April 3, 2008 11:37:21
From:	Richard Jackson (
The telescope we have is the ETX-90EC
Mike here: Cheap and reliable don't always go together. I'd recommend the Meade #884 tripod for the ETX. Provides both Alt/Az and Polar mounting on a good stable mount.


Thank you

Subject:	Aligning Without Polaris
Sent:	Wednesday, April 2, 2008 15:49:25
From:	Steve Hollar (
I'm a bit baffled. On one of the posts, someone had asked how to do a
Polar (Equatorial) alignment when Polaris was not visible. That is my
problem at my house unless I decide to chop down a forty foot eucalyptus
tree. This is what you said:

"one that I use when I can't see Polaris, is to use the compass or guess
where True North might be. Then do the first alignment star but instead
of slewing the telescope, pick up the telescope and tripod and rotate it
horizontally until you get the telescope pointed as close as possible to
the proper star and then slew to center it, first in the finderscope and
then in an eyepiece. You have now corrected for the initial HOME
position. The second alignment star should be close and you should
center it normally."

So, you are saying to do a rough Polar Alignment, then pick an alignment
star and literally turn the scope and tripod to point at the star
followed by some tweaking with the slew controls to center? After that,
I'm assuming you mean to do a regular Go To single star alignment, which
would actually be a second star.

I thought that the tilt platform, that had been raised to your latitude,
has to stay pointing at Polaris. By moving everything, it will no longer
be. Doesn't this throw everything off?

Maybe I'm reading this wrong. Can you shed a bit more light on it?
Thanks, and, I have learned so much from your site. It is a true asset
for amateur astronomers.

Steve Hollar
Lake Elsinore, CA 
Mike here: Whether in Polar (Equatorial) or Alt/Az, moving the entire telescope/tripod assembly to align the first alignment as close as possible will result in the system being in nearly the correct HOME position. In Polar mode, as long as you have set the tilt for your latitude, when you rotate the tripod horizontally to the first alignment star the Right Ascension axis should be parallel to the Earth's rotation. Again, you are correcting for positioning error in the initial HOME position. Then proceed with the second star alignment as normal. If you want to do a more precise polar alignment, do a "drift method" of correction.
Subject:	MyStar - Theory of Operation?
Sent:	Wednesday, April 2, 2008 09:00:56
From:	Doug Criner (
MyStar acquires the time, date, and location from GPS. But how does it
"know" the altitude and azimuth of the direction it's pointed?

Meade says there are sensors - and some people seem to think they are
magnetic? I can't visualize a magnetic sensor being accurate enough for
azimuth. I can't imagine how a magnetic sensor could measure altitude.

Doug Criner
Mike here: I'm not familiar with a "MyStar". If you mean the Meade "mySKY" then it does use sensors to measure how it is moved. When you place it on a level surface after the GPS acquisition it "knows" the zero point. This is similar to how the iPhone determines that it has been rotated from a portrait position to a landscape position.


Thanks, Mike.

Yes I meant mySky.

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