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Last updated: 23 June 2013

Welcome to the AutoStar feedback page. This page is intended to provide user comments on using the Meade Autostar #494, #495, #497, #497EP, AudioStar, cables, and AutoStar updater software. See the AutoStar Info page for information from Meade and other users on the AutoStar, cables, and software. Send your comments and tips to for posting. Please use an appropriate Subject Line on your message per the Site Email Etiquette. Thanks. Remember, tips described on this site may invalidate the warranty on your telescope or accessories. Neither the submitter nor myself are responsible for any damage caused by using any contributed tips.

Subject:	starseeker wifi and meade ls8 acf
Sent:	Friday, June 21, 2013 15:49:00
From:	John Massey (
Does the Skyfi Wireless Telescope Controller with USB work with the
Meade LS telescope? I have a Autostar 3 handbox and I'm at a loss trying
to figure it out. Your help would be greatly appreciated.

John Massey
Mike here: According to the Southern Stars SkyFi web page, the Meade LS is supported.


Thank you very much for your response. Funny thing, the telescope works
fine when I usb cable between my laptop and usb port on the telescope
running Autostar Suite. But I get an "unable to connect" with the Skyfi.
I talked with a guy at SouthernStars and he was at a loss to.
Mike here: I've only used Wi-Fi via the serial connections on my ETX and LX200-ACF telescopes.


Ah right. I'll find one and give it a go! 

Thanks very much for your help Mike. 


Subject:	Re: ETX125
Sent:	Tuesday, June 18, 2013 11:47:19
From: (
I put fixing my ETX125 aside until inspiration strikes, or I get
feedback from that gentleman in South America, ~2004 on your Site, who
seemed comfortable with removing motors and still getting them back
together! My relatively non-invasive attempts to clean up the grease on
the encoder hasn't worked so far, and each time I test my results I
encounter other problems!!! For example, on the first reassembly using
the RA drive caused a jump in AZ when viewing stars! That seems
impossible, but it did! On second test after further cleaning, I 'lost'
the AZ drive completely, but after fiddling around, the clutch mechanism
started working again. The dam thing seems to hang by a thread!

But I've used the EXT125 with just motor steering, to view Saturn and
the Moon, and the optics are superb. If nothing else, I've got a great
little 5" cat.

That Meade LX200R that I got cheap $600 on A-Mart, like yours, is so
darn good that I'm hardly inclined to use anything else! Bought a new
Celestron CG-5 equatorial mount with its own 'nextar' for all-around
testing of the 5" telescopes, and it is such a pleasure to use compared
to anything I ever bought from Meade, and it is stout enough to easily
support the 8" SCT.

Regards, Dick.

Subject:	Autostar question
Sent:	Saturday, June 15, 2013 06:33:51
From:	Snedden, Kevin (
I came across your site and got this email address.

I am hacking together a CG5 type clone from bits collected over the
years. I modified the motor brackets to hold Pittman DC gearhead motors
with encoders.

My intent was to use a SiTech Servo 1 but my Si Tech has since gone into
a belt driven Alt Az that I like too much to mess with.

Another SiTech will run me $400 then I still need to lug a battery and
laptop to make it work.

The intent of my new mount is for grab and go visual with GT.

There's some info I can't seem to find on the internet.

Does the Autostart drive servo motors? Or is it a stepper driver?

Can you recommend a handheld controller that may do a similar function
with DC motors?

I would like to keep the cost below $200.

Mike here: Steve Bedair's GOTO Telescope Mounts web site ( has lots of info that might help you. Also, you might want to check into the Roboscopes Yahoo Group (http://groups.; lots of great info and help there. As to the AutoStar explicitly, I'll let our resident AutoStar Expert, Dick Seymour, respond.


It's kind of amusing...
Steve's Bedair's site is where I got the link to your site.

I'll keep looking around. Thank you for the response.



From:	richard seymour (
To answer some of the questions:
The Autostar (for example, the 497) sends messages to smaller "motor
control cards".

Those cards perform the tight closed-loop to maintain whatever speed the
Autostar requested.

The motors Meade uses are simple DC analog motors (not steppers), with
quadrature encoders mounted on the shafts.  The "motor cards" read the
encoders and send PWM power to the motors.

The Roboscope group's Files area has notes on using other motors, or
"beefing up" the H-bridge powerFET drive stage of the motor cards.

hope this helps

Subject:	re: Problem with AZ(RA) drive on ETX 125AT  from 2006
Mike here: The owner came by on Thursday and I did some troubleshooting. The problems (not correctly pointing to alignment stars and slewing to a hard stop) were not resolved. The AutoStar was running 4.3Ea. I suggested updating to 4.3Eg, which is the latest, best version for the original AutoStar #497.

And this:

Subject:	Meade 505 serial to usb cable for older (7 years) ETX125    061413
Sent:	Friday, June 14, 2013 08:54:51
From:	RABuchroeder (
Already need your advice on the cable.

Amazon has a product intended specifically for the Meade ETX to USB
situation. Most other cables don't have the appropriate connector to my
Autostar, which visual inspection shows me to be the same as a phone
plug, and with just 4 junctions.

Meade #505 Compatible USB to Serial Adapter Cable for Meade ETX 80, 90,
105, 125 Telescope #497 Autostar

by ATOZstars

Special for PC computers without a serial port
Meade Serial Interface Cable for #497 AutoStar Controlled Telescopes Cable Set
60 inch Meade #505 compatible cable. 12 inches USB to serial adapter cable
Windows 7 (32 bits) compatible
1 new from $27.50
Mike here: Not all USB-serial adapters work reliably with the AutoStar. I recommend only ones from Keyspan. Since this one "claims" to work with the AutoStar, it may be OK for some, if not all, operations (updating, telescope control from a computer). The #505 serial cable is just a basic phone cable with RJ-11 connectors. However, it is wired differently to the connectors than a phone cable. For more info on cables and USB adapters, see the Helpful Information: AutoStar Info page on my ETX Site.
By the way, I must apologize. If my brain had been working better last night, we could have updated your AutoStar from the one on my ETX-125 using the "cloning" technique where the two AutoStars are connected to each other.


I talked to Meade tech support minutes ago, and he said that the latest
software download should work with my older ETX Autostar. (our thought
being that the existing software may have become corrupted, so that
downloading the current version will overwrite it).

Meade Store sells an adapter cable, probably the same as the one on
Amazon, after adding the additional USB adapter it requires.
Unfortunately, like several products lately on the Meade Store, and at
its resellers at telescope outlets,  this product is back-ordered, which
may mean unlikely to be available in the forseeable future while
ownership of Meade is sorted out.

I've left a message with my computer-literate friend, James,  asking
whether it's difficult to switch back and forth between 32 and 64 bit
Windows 7 operating system, since I'm running 64 bit and that software
won't run on it.

Will keep you posted.

Regards, Dick.
Mike here: Meade's USB-serial adapter has also been problematic for some users. I still recommend only Keyspan. As to using the latest AutoStar ROM with the old AutoStar #497, DON'T DO IT. Stick with 4.3Eg. I also suggest using the Meade AutoStar Update application 4.6. You can get the ROM file and the updater from the AutoStar Software Archive on my ETX Site. Alternatively, you can use StarPatch (free from to do the updating. StarPatch is more forgiving of problematic USB-serial adapters.

And this:

From:	James
If I understand correctly you are saying you can reprogram the
controller with old firmware through the PC connection if you can get
the PC software running?

Supposedly Windows 7 will detect 32 bit software and install it in the
appropriate Program Files (x86) directory and be able to run it in a 32
bit mode. Windows 7 x64 has some extra compatibility mode settings that
will make it run a program like it was XP, Vista, or 95. However if this
software needs to change things in the Windows directory beyond running
an exe then it may not work with Windows 7 x64. (It would be worth a try

Let's assume you need to go to Windows 7 32-bit (or pick any older 32
bit OS). Assuming no licensing issues (probably can't use an upgrade
version of the OS but rather a full install version) if you are willing
to sacrifice what's on the computer it is possible to install the old OS
obliterating the current one. A more complex solution might be to get
drive partitioning software to do a dual boot setup where when the
computer starts you can select the "C drive" to boot off of and not
delete your current OS, assuming there is plenty of hard disk space for
two separate operating systems and the dual boot can be done after the
fact. I've not done that to a computer in 20 years so it would be new
ground for me, but people who play with computer operating systems do it
all the time.

Perhaps the least costly solution would be to borrow a computer with a
32 bit OS long enough to do the upgrade. I for example have a Windows XP
32 bit notebook that I was just about to wipe clean. Maybe it has enough
horse power left in it as it is to limp over the finish line for this

You'll need access to the version of the firmware you want to install on
the controller. Do you have that or is that available?



Mike here: The software to do the update and the firmware are available from my ETX Site.


Ah ha. Great site.



The cloning only requires that you have my Autostar paddle, nothing more
from the telescope?

If so, how would you feel about my mailing you the paddle, let you do
your magic, then mail it back to me?

That would be the easy way out for me. I see that you do have a
postoffice there in Oracle, not closed yet in the wave of closings.

Since I'm in no hurry, that would be easier than me driving up there  (1
hr. 15min) each way.

Please advise.
Mike here: Well, not exactly. The AutoStar needs to be powered, which comes from the telescope. Each AutoStar needs power from its telescope.


I wonder if any of your smaller ETXs would power my Autostar paddle?
Even then, I wonder if the success of the new software is contingent
upon the specific Autostar paddle being connected to the specific ETX125
in question?

Worst case, I can wait until the next time I come up to Oracle.

Otherwise, issues with cables, operating systems, etc., are looking to
be a BFD.
Mike here: I thought about that. Conceptually it should be ok but given the age of your system, I felt it would be safer to clone to your complete setup. If you do get the cable and update going, then you'll have the capability for updating/restoring the AutoStar should it get corrupted in the future. But your choice how you want to proceed.


The inspection sticker on the base is 12/1/06, so it is less than 7
years old, despite what the operating system coming up on the Autostar

What do you think is the worst that could happen if I sent you my
Autostar paddle and you did anything you wanted with it, and then mailed
it back to me?
If the whole thing goes up in smoke, I'll still have a good OTA that I
can push&shove manually.

Messing with an uncertain cable and my microsoft OS makes me nervous.
I'd rather it were a last resort, rather than the first.

Please advise.

Thanks! Dick.
Mike here: I can do the cloning here. You would then have to do all the "new" AutoStar stuff; RESET from your telescope, set up your location, CALIBRATE MOTOR, and TRAIN DRIVES. Hopefully, the problem would be resolved. I just ask that you pay for return shipping.


That's what I wanted to hear!
The Autostar is helpful in steering, which is the reason I don't mail it
off today.

And this:

I'm tempted to remove the baseplate to see if there's oil or grease on
the AZ optical encoder.

Everything else works so well on the Autostar paddle that I find it hard
to believe it could be defective.

The uncontrollable AZ motion suggests failure to communicate with the AZ

Any advice on recognizing the encoder (I don't know what it looks like),
and then cleaning it with rubbing alcohol and paper?

Please advise! Dick.
Mike here: Possible but since you report that slewing is reliable when not doing the initial alignment, it is likely that the encoders are working OK. But won't hurt to check.


Can you briefly tell me what the AZ encoder looks like and whether I'm
liable to wreck it if I'm too heavy handed?
Mike here: Lots of articles on encoders and gears on the Helpful Information: Telescope Tech Tips page. And yes, heavy-handedness is a culprit in damaging internals on anything.

And this update:

Took the bottom off.

I see that if I were to break the red/black wires from the bottom plate,
it would only make the batteries useless. The external power supply
socket would still work, and that's how I run it.

Here's my understanding of the AZ/RA Encoder, from what I can make of
the hardware in front of me.

The encoder appears to consist of an outboard black pillar, and an
inboard waxy white pillar.

The plastic spur gear on the motor shaft runs between these two, and is
supposed to transmit and sense a beam of light each time a tooth goes


Thick green grease all over the place, especially between the tiny teeth
of the motor's spur gear.

Bad idea: using a cotton Q-tip to clean it off.
a. It doesn't work
b. you snag cotton threads in the goo, making the whole thing worse.

I had to split a wooden chop stick to get the cotton threads out; can
see that the grease is still closing the gaps in the gear teeth.

It is almost impossible, with ordinary tools, to clean the grease off
the spur gear, because the base walls prevent you from being able to get
in close and personal with the gears.
Looks like the entire gear structure is held to the metal foundation
with three small Phillips-head screws. This structure needs to be
removed so the teeth can be washed clean.

My prior experience with trying to clean and take the play out of the
nylon gears on an ETX-90 (which was also slathered with grease) makes me
leery of taking those screws out, because on the ETX they also retained
the shafts of some of the gears, and putting them back together was a
real mess.

So, I'll have to sleep on this. If I leave it like it is, at least I can
steer the telescope with the motors on both axes, but can't use the
Autostar database to track the stars and to find objects.
If I fail to put the gears back together, I'll lose all motor control.
Because of the precipitous clamping on the DEC axis, using motor
steering is highly desirable.

I'm 99% certain the problem is grease in the gear teeth, not a problem
in the Autostar. Slovenly assembly with too much grease in China (this
one was made in China), heat in Arizona that softened it and let if flow
over the small teeth, blocking the encoder light path.

Will let you know if I throw in the towel, or try to fix it. Want to use
it tonight to view the moon, so I think I'll put off that decision until
later. Have guests on Saturday and on Sunday that may want to view with

Regards, Dick.

And more:

Attached is an image taken wih the assistance of a flat mirror laid up
against the gears to show the timing section.

I've got the timing gear cleaned, but probably not the encoder, which
appears to consist of an emitter (clearish plastic appearance) and a
receiver (the black thing with the blue dot on the top).

The black thing doesn't  have an aperture on its face...pretty much like
the obelisk in 2001. So, maybe it just senses a change in light level?

The clearish plastic thing, on the other side of the timing gear, can't
tell, but I'd guess it puts out a beam of light/IR and the teeth
interrupt it, providing a count or a frequency interpreted by the
Autostar system.

Is this indeed the 'encoder' for the RA/AZ drive?

What's the logic: emit light from one side, chopped with the gear
directly attached to the motor, receive on the opposite side?

Regards, Dick.


Another view of the encoder area, reflected image with a flat mirror.


Mike here: Perhaps the articles "Encoder Fix" and "Cleaning the Encoders" on the Helpful Information: Telescope Tech Tips page will assist. But basically the AutoStar counts pulses from the optical encoders to determine how the gear is moving. CALIBRATE MOTOR measurements the power output from the light and TRAIN DRIVES counts the pulses vs movement.


The 2004 readers contribution says he had a grease-slathered gear and
encoder assembly that were causing his trouble.
He seemed to be very comfortable removing the motor; something that
scares me since it is at the bottom of layers of plastic and circuit
But his image confirms that the pictures I sent are indeed those of the
encoder for the RA.

I will proceed with caution, if I proceed!

Thanks, Dick.

Subject:	How to setup autostar with a meade ETX-70
Sent:	Thursday, June 13, 2013 10:57:49
From:	Jason Blonar (
My name's Jason and I'm hoping you can help with a dilemma I'm having
with my Meade ETX-70 telescope.  I've looked through your site and am
impressed by what I've seen.  My problem is I that I haven't had any
luck getting Auto Star (version 3.1; I believe) to work with the

I ordered the connector/conversion cable from Meade in order to connect
the telescope to a computer with a USB port; but after attempting to
install and run the program, I found that I was unable to.  The computer
in question is an Asus laptop running Windows Vista.  The computer also
has installed on it Starry Night Pro v6.

I'd appreciate any help you could provide.  Sincerely,
Jason Blonar
Mike here: First, lets deal with the problem without the computer. What is the problem you are having with the AutoStar on the telescope? Also, what model AutoStar? #494 (not number keys on the keypad) or #497 (has number keys)? Need more info. As to using a computer, be aware that not all USB-serial adapters work reliably with the AutoStar. I recommend using Keyspan adapters.


Thank you for the quick response; we have #494 (without numbers).  It's
getting older and the buttons don't work as reliably as they used to. 
With the USB-serial adapter; I got that off of the Meade website,
shouldn't that work?
Mike here: There is a tip on the Helpful Information: AutoStar Info page about cleaning the keypad. That might help. As to the USB-serial adapter, maybe, maybe not. If you have the #506 serial cable (has electronics in the cable, unlike the simple #505 serial cable) and you have a supported version of Windows, it might work.


I will take a look at that helpful information section.  How would I
know which cable I have?  We had to go to the Meade site to download the
drivers for Vista to support it
Mike here: The #506 serial cable has a black plastic box at one end which holds some electronics. The #505 serial cable looks like a cable that could connect a telephone to a wall jack (but don't try that, it is wired differently) and has no large black box, just the small plastic RJ connectors at each end.


The #506?


Mike here: Sure looks like one.


Now that we've established that I have the #506; how do I go about
installing everything so the computer controls the telescope?
Mike here: First, you need to know that you have working connection. Have you installed the AutoStar Update application and/or AutoStar Suite (both from Meade)? Or install StarPatch (free) from See if one of those programs will connect to your AutoStar. You might also want to look at the article "AutoStar & Your Computer" on the Helpful Information: AutoStar Info page.

And this:

We've installed the Auto Star Update 
Mike here: Does it see the AutoStar?


yes it does
Mike here: Good. Then you know you have a connection. You can now try to get Starry Night to connect and control the telescope. Follow its documentation. If the ETX-70 is not listed in a connection dialog box, just select the ETX-90 model. It may still work.


it keeps giving an error 'clear Autostar Cable and try again.'
Mike here: Is that from the ASU program? If so, try StarPatch; it is more forgiving of USB-serial adapter issues.


Okay; i'm looking at the site...what file should I download for starpatch?
Mike here: StarPatch "Free trial version".

And this:

from the downloads screen, correct/?

Star Patch is having trouble connecting to the telescope; so I'm think
it's the adapter or the autostar of them may need to be
Mike here: Could be Vista and the Meade adapter. Search the ETX for "autostar vista" and you'll get lots of hits. You might need to update the Meade driver at


I will look into that...thanks

Subject:	Audiostar setup for ETX-90
Sent:	Saturday, June 1, 2013 13:57:30
From: (
I have a new Audiostar 497EP A3S4 and few month old ETX-90.  My question
is what telescope model should be entered under setup?  There are
ETX-69, -70, and -80 listed but no ETX-90 model listed.  Thank you for
your help.

Sent from my iPad
Mike here: I don't have an AudioStar so can't answer directly. But I'm surprised the ETX-90 is not listed. You can select the ETX-80 (the optical calculations by the AudioStar would be affected) but it should still work to control the telescope. Remember to do a CALIBRATE MOTOR and TRAIN DRIVES. Perhaps our resident AutoStar (and AudioStar) experts Dick Seymour and/or Andrew Johansen have some other thoughts.


Thank you very much for your prompt reply.  I'll wait to hear from Dick
or Andrew and also see if Jose or Luis at Meade can help me on Monday
too. Curiously the V43Eg firmware currently on the original Autostar
(now deemed defective by Meade) that shipped with the telescope in
December also does not list the ETX-90 as a telescope model option in
setup.  That Autostar when shipped with the telescope had another
firmware version, V45Ed dated 2012 but this is not available on the
Meade download site.  I confess that I do find it strange these multiple
and selectively available versions and the disconnects in their
instructions in setting home (not updated for the "new" ETX-90 with the
6 AA pack and computer control ports/switch moved to moving fork
assembly and DC input power port delete) - but I drift off topic. 
Hitherto my goto experiences have been with a range of Celestron
cassegrain models ranging from 4 to 11 inches.  I bought the ETX-90 for
its portability and based on over a decade of curiosity. Hope to get it
to work.
Mike here: 4.3Eg is the and last version for the old AutoStar #497. Really odd the ETX-90 wasn't listed.


From:	Andrew Johansen (
Im going to assume this is one of the new model ETX-90s.
If so, they appear to use a different motorcard and gearset to all the
other ETX-90s ever listed.
They are in fact common to the very original ETX-60/70/80 models.
We know these new ETX-90 models were being issued with old style 497
Autostars, with 45Ed firmware.
This new Firmwareonly shows up on a Russian Meade site ( that we have
found to date :-)  )
The 497EP and Audiostars have no knowledge of this new model.
To get around it, just select ETX-80 and all should work correctly.




Many thanks.  Yes there are a number of features of the "new" ETX-90
including I think a different home position setting procedure in azimuth
(there is no hardstop) that aren't clearly documented.  Can you tell me
the link to the Russian site with the 45Ed download?  I inadvertently
downgraded to 43Eg when I ran the Autostar Updater after purchase. 
Meade deemed the handcontroller defective subsequently due to some
memory error related messages (and kindly sent the Audiostar as
replacement) but I am not so sure.  Will try the ETX-80 setting in
setup.  Thanks again and thanks to Mike for his great website and



> Yes there are a number of features of the "new" ETX-90 including I think
>  a different home position setting procedure in azimuth (there is no 
> hardstop)
> that aren't clearly documented.

They ALL start by pointing the OTA Nth and level.
The models with a hardstop had a different startpoint ( up against the 
hardstop )
but ONLY if you were doing a full autoalign.
For normal one or two star aligns, these scopes still used Nth and Level as 
the start point.

> Can you tell me the link to the Russian site with the 45Ed download?

>  I inadvertently downgraded to 43Eg when I ran
> the Autostar Updater after purchase.

I personally would stick with 43Eg ( patched if desired ) vs the unknown 
Just select ETX-80 as the model and you are off and running.


And this:

Many thanks for your and Andrew's help!  I also enjoyed wondering around
your site.  Amongst several things the recent ISS lunar transit shots
have inspired me.
Mike here: Thanks Steve! That ISS-Moon transit really surprised me at how well it turned out. I've done some others but they weren't as nice.



Thanks once more.  Will give the ETX-80 setting a try and thanks for
confirming the Az home setting procedure and being so much more
informative than the manual.  I'll try it after dinner now with our next
door neighbors, an Australian family returning to Canberra later this
month after a three year posting in DC.

All the best,

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