Last updated: 31 January 2002
Welcome to the Autostar feedback page. This page is intended to provide user comments on using the Meade Autostar, cables, and the 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 Remember, tips described on this site may invalidate the warranties on your ETX and accessories. Neither the submitter nor myself are responsible for any damage caused by using any contributed tips.
Subject:	Using the Optimising Training Values Spreadsheet on my DS-127
Sent:	Thursday, January 31, 2002 3:08:52
Hi Martyn,
Using this spreadsheet has been a great help. I could never get my scope
trained properly as the values would be different each time. I ran
though your process and noticed that the Az graph formed a reasonable
line where as the Alt was all over the place. I ran through the process
again and the Alt values where again all over the place. This had to
mean that the Alt axis must be slipping or sticking.

The DS scopes have a few adjustment you can make to the gear train. One
is a brass nut that tightens the worm gear and the other is an Allen key
screw that adjusts how close the worm gear is to the spur gear. I
suspected that I had over tightened the gear. I loosened it and ran
though you procedure again and now both axis had good straight line
graphs. The scope now re-centres a landmark almost perfectly! I haven't
tested it on the sky but I'm off to a dark site this weekend and I'm
sure the tracking and goto will be greatly improved.
Raymond Barbour
South Africa

Subject:	autostar command set
Sent:	Tuesday, January 29, 2002 14:40:07
From: (marcus)
I've been a fan of your site for quite a while, and I own an ETX-90EC
with Autostar.

I had a question about the command set on the Autostar. I'm trying to
run it from the serial port of my computer, and I got some things to
work, but I'm having trouble with some others.

I can get to any object I want by typing the DEC and RA manually, and
using # :MS# to send the telescope there.

Looking at the command set that Meade provides for the LX200 and
Autostar, there are some differences. The commands used by the LX200 to
slew to a desired Messier Object or using # :LM ****# or #
:LS ****#  are ignored by the Autostar. So my question do
you slew to an Messier object or planet without having to enter the DEC
and RA directly?? This isn't too bad for Messier objects, but planets
move too quickly to always know the RA and DEC. I know the Autostar
calculates this for you, so how do i tell the Autostar to do it, so I
don't have to?

I looked at the archive of "Autostar Command Set" info on your website,
but I didn't find anything concerning slewing to planets.

Thanks for your help.


Marcus Windrich 

Subject:	The 22" Telescope project
Sent:	Monday, January 28, 2002 23:00:06
From: (Vicki Smith)
I am sending you some pictures of the telescope that I am going to put
the AutoStar on. I have decided to use Method 2 that I described in an
earlier letter. I have started to modify the ETX gear box by removing
the unneeded gears and making spacers. I purchased new pulleys for he
telescope that will give the new final ratios. I will machine the
adapter clutches for the ETX worm gears soon (I hope). I have know idea
how long it will take to complete this project. As you can see the scope
currently has a Celestron CompuStar. It works well but as I said there
are problems.

The telescope is 22"a f4.3 newtonian. (Someday I hope to add a
Cassegrain focus). The telescope fork stands 64"to the top of the dec
housing. The box the tube is in is 77" off of the ground. The tube is
91" long. The fork is made of .250" aluminum plate. The fork is a
weldment with the Dec shaft housing an aluminum casting. I think the
whole thing weighs 1500lbs. The foot print that the scope occupies in
about 6' x 6'. The A frame and cradle are 4"x 5" .250" wall Al Tubing.
The polar disk rests on 16 sets of 1" bearings, (total 32") in a rocker
cradle. The rocker cradle is supported on by a weldment of 1/2" Al
plate. I constructed the telescope over a period of 2 years while I was
in college. I collected parts for about 4 years. The Mirror is made of
Hayward c3. It is 2.5" thick and weighs about 100 lbs. It took about 80
hours to grind and 200 hours to polish and figure the mirror on a
machine that a friend and I built. The compustar works fairly well. I
have to change the RA and DEC ratios, the park horizontal, and the RA
direction bits on startup. Other than that the the CompuStar works
pretty well. I have a deep cycle marine battery for the power supply. It
seems like it will work for an entire nights observing. My next project
is to get the trailer and scope mated for transportation.

telescope telescope telescope


From: (Steve & Cathy Bedair)
It's a beautiful scope! and a lot larger and heavier than I had
imagined. With enough gearing between the etx motors and the scope it
should work. I would imagine it's going to be very slow. Be sure to keep
us updated on your progress and I'll add it to my web site. ( Your mount
makes my 10" GEM mount I've just started on seem tiny )
Good Luck and keep up the good work,
Steve Bedair
Thanks. The scope just grew from the original 14" that I imagined. I
don't think that I noted the ETX 60 mounted as the finder. I am actually
shooting for a similar gear ratio to the ETX. I think that I can do this
for two reasons. 1)  the current Celestron CompuStar motors are 53 in oz
with a ratio of 720:1 the ratio for the ETX is like 8000:1 or about 12
time the ratio. Since the CompuStar can drive the scope I think that the
ETX can too. 2) The final drive disk is 26" in diameter. That represents
allot of torque advantage. I have tried to stop the ETX motor drive
train with my  hand and it is very difficult. I should be able to drive
it at the ETX rates. Concerning the 10" that you are building, you can
move it a lot easier that my scope. I also have a 6" cassegrain that I
have used more than the 22" for that very reason.


Subject:	autostar update
Sent:	Saturday, January 26, 2002 21:47:16
Howdy from Texas,
I've been enjoying your sight ever since I've stumbled upon it surfin
one night. Wow, the resources I have now about the ETX. I've already
gone through a full ream of paper printing out everything you have to
offer. I purchased an 125 off of Ebay and have not encountered any
problems that have been mention on your site -knock on wood. I consider
myself a casual but experienced observer and I am wondering about the
necessity of updates for the Autostar. My Autostar has version 1.2
loaded in it and I am wondering if I will have problems updating to the
latest version of Autostar. Do you have any recommendations or concerns
on updating this "old" firmware? I love my ETX and it is a good
companion scope to bring along with my 10" dob.

Clear Skys and Thank You.
Mike  S. in Texas
Mike here: You shouldn't have any problems upgrading to 2.3Eb (the current version) from the old one. The only problem one person noted was that it was necessary to put the Autostar into "Download" mode first with the older version. Once upgraded you no longer have to do that.
Subject:	Re: ETX training improvement
Sent:	Friday, January 25, 2002 4:07:30
From: (Martyn Edwards)
To: (Victor van Wulfen)
Hi Victor

I've just downloaded the latest Meade 23Eb and put Dick Seymour's new
patch onto it. I won't have time to play with this for the next week or
so due to business, but I'll let you know how I get on.

The reason that I suggested that you park the scope rather than just
turning the power off was that in the last build the training values you
set would download into the Autostar on either a Power Off / Power On
sequence or Park / Power Off / Power On sequence. I'm not sure what the
current build does yet.

In my spreadsheet ( )
I suggested that you Park before powering down because then you don't
need to carry out a dummy alignment (i.e. Easy alignment and just accept
whatever position the scope goes to and press enter - it's only
necessary to 'persuade' the Autostar that it's level) when you turn the
power back on again. However, in the spreadsheet procedure it doesn't
really matter whether you Park or not - if you don't Park then just
carry out a dummy alignment after turning the power on. It just takes a
little longer, but the basic process remains the same.

As far as improvement is concerned, yes it's made a really significant
change. I was never really happy before - whenever I did a GOTO although
the object was always visible in the finder and usually ended up in the
field of view of a 26mm eyepiece I found that after centralising the
object the Autostar had a tendency to try to move away again.

Typically this occurred when I was moving the telescope in the opposite
direction to the way the ETX was trying to go to counteract the earth's
rotation, and I felt that the ETX and I were trying to fight each other
to get the scope to go where I wanted it to and stay there.

I think this was known as 'rubber-banding' and, pretty obviously, was
due to the change in direction of the azimuth and/or altitude motors
after I had finished prodding buttons and the Autostar then started
tracking again, and the consequent amount of backlash which the Autostar
thought it should apply - and these values were incorrect. Using the
spreadsheet to calculate the optimum training values has cured this
problem and I am delighted with the results.

After Clay Sherrod's suggestions for improving ETX performance -
especially degreasing - I believe that getting the training values
sorted is probably the single most important thing that an ETX user can
do to improve performance.

I would also suggest that after you have set the optimum training values
that you try to keep the azimuth and altitude percents low - zero if
possible - because the last thing you need is a kick applied to the
motors when you reverse the motor direction which takes you past where
you want to go!

I'm copying this to Mike Weasner in the hope that he'll post it here: and Dick
Seymour who is a great guy doing a brilliant job for Mike's excellent

Best regards,

Martyn Edwards
  ----- Original Message ----- 
  From: Victor van Wulfen 
  Hello mr. Edwards,

  I downloaded your spreadsheet from Mike Weasner's site and it looks
  very promising! I haven't been able to try it though, bad weather has
  kept me inside today.

  I have one question regarding the procdure you advise. You say, as
  part of the process, "enter the new (calculated) training values, park
  the scope and turn it off."

  However, Richard Seymour says the following in his patch (23bb,
  available today, I attached it to this e-mail):

  Autostar Menu items added by this patch:
  ;  Training results Display and Edit:
  ; Under Setup > Telescope > Train Drive
  ; are now (scroll up or down from the "Az/RA Train" or "Alt/Dec Train")
  ;  Edit: > Az/RA Train
  ;    and
  ;  Edit: > Alt/Dec Train
  ; press [enter] to allow direct display and manipulation of the results of training.
  ;    a power cycle (without using Park Scope) is needed for
  ;     the  new values to be fully implemented.

  A problem in the process could thus be the implementation of the new
  values by switching the scope off without using park. Do you think the
  affect is considerable or can it be disregarded? Were your GOTO's
  better? I'm really curious about the results and look forward to
  trying it.


  V.A. van Wulfen

Subject:	Updater with 494/506 cable
Sent:	Thursday, January 24, 2002 20:53:12
From: (wilbur, ted)
I've got an ETX 70, AutoStar 494 with 506 cable.  I believe the cable
and com port are all set since I can control the Autostar and slew the
scope with the Astronomer's Control Panel and Starry Night software that
came with the cable.  However, the Astronomer's Control panel shows the
current Autostar date as 07-Feb-06, way off.  It almost seems that the
application is not looking at the correct AutoStar bit bucket for the
date.  Not a big issue since I bought the cable to use the Updater, not
control the scope with the software.

My real issue is with the Updater which I wanted to try just to retrieve
the data in my unit and to get used to the process.  The updater wont
connect to the AutoStar (as mentioned, I think the cable and com ports
are configured and working properly).  Do I have to put Autostar into
"Download" to establish the connection (looks scary so I haven't tried

Mike here: You need the ACP update from As to the updater, it should connect but there is no Autostar update available for the #494. Check your settings and look for some other app that has the port in use (like fax software).

And an update:

Correct on both counts, all working now, thanks.  My apologies on the ACP
question, rule #1 when diagnosing software issues: check for patches on the
vendor's website.

Thanks again!

Subject:	ETX Autostar problem
Sent:	Thursday, January 24, 2002 2:20:01
From: (Mark Aston)
I wrote you last year about my Autostar that effectively broke during
software update; I have now got to the bottom of what happened and got a
new Autostar free of charge from Meade.  This may help anyone is a
similar situation.

All you folks beware of an unlikely, but terminal problem with Autostar.
Have you ever wondered how the recovery mode works?  It is very simple;
in the Autostar (all models) there is a PIC microcontroller that
performs the primary function of scanning the keyboard.  When you first
turn Autostar on, it is the PIC that wakes up first and scans to see if
you are pressing the right key combination to put the Autostar into
download mode.  At the same time, it wakes-up the primary processor
which handles display etc.

The code in the PIC is VITAL to operation of the Autostar, so if the PIC
goes down (for example due to voltage spike on power-on) your Autostar
is dead, finito, no going back!!  You can tell that it is this problem
in that there will be no display, no backlight and no LED reading light
on Power-on

Meade will not sell PICs separately, nor highlight the PIC code or
distribute it, so either it is 'back-to-base' for a repair charge, or
politely moan about the fragility of the Autostar PIC to Meade.  In my
case (and being based in UK), it resulted in a free Autostar, shipped
free of charge to UK within 5 days!  The person who sorted this for me
was Tom Hoang.

Hope this helps those who maybe scratching their heads as to what has
gone wrong.

Clear skies, all!

Mark  Aston

Subject:	Misplaced moon
Sent:	Wednesday, January 23, 2002 13:43:14
From: (Donald Davenport)
Your site is a bonanza of great stuff.  Thanks!
I have a ETX-90EC which I use polar aligned.  The Autostar  [v.2.0] is
surprisingly accurate, often placing objects in the eyepiece and always
in the viewfinder.  Except the moon.  The moon is never centered and
often not even in the viewfinder.  (Granted, it's not hard to find, but
it seems strange that a device that can find deep space objects without
breaking a sweat can't center up on the moon.)  Anyone else report this?

Donald Davenport
Mike here: I suggest upgrading the Autostar if you can. If you don't have the cable/computer then perhaps your dealer (or someone at your local astronomy club) can clone it for you. The Moon's position changes over time and the data for the calculations require the occasional updating. I don't know what algorithm Meade used but the data is more current in newer versions.
Subject:	Re: altitude problem
Sent:	Wednesday, January 23, 2002 7:50:58
From: (
In your opinion is it the scope or is it the autostar. I don't want to
send the scope back if I don't have to it is out of warranty. That was
the reason I asked about what Meade does to fix them.   Thanks again
Mike here: It could be almost anything from the gears, wires, or circuitry in the ETX base to the cable to the Autostar itself. Swapping out controllers can help determine which end has a problem.
Subject:	LXD55 Support on Autostar
Sent:	Wednesday, January 23, 2002 3:00:54
From: (Bob Rose)
The LXD scopes use the LX90 family of motors. Since around 2.2E, the
autostar has programming to recognize motor families. What this means is
that what scopes that are displayed in the "Telescope" menu depends on
what scope base the autostar is plugged into. An autostar plugged into a
DS scope displays DS and some ETX models. An autostar plugged into a
LX90 displays LX90 and the LXD series. The autostar will remember the
selected telescope model even if it is plugged into a different  motor
family. An autostar previously set up with an LX90 will try to operate a
DS scope as a LX90 even though it will not display the LX90 telescope
from the menu when plugged into the DS scope. If you are need to operate
a DS scope in polar or gem mount two option exist. 1. Plug the autostar
into a LX series base and set it up for the LX then move it back to the
DS scope or you could try Dick's patches at

Clear Skies
bob rose
Sent:	Wednesday, January 23, 2002 6:45:53
From: (hpwallner)
I saw your post on M.Weasner`s site about acess to a GEM setup with

There are two  possibilities:

1) Install Dick Seymour`s Patch Kit v23b4 - you can find it on Mike`s
site under Autostar Info 
-> Patches.
If you install this patch the following Telescope Models are available:
DS60, 4504/114EQ, DS80, DS90, DS114, DS 127, ETX70, ETX90, ETX105,
ETX125. Note -no DS 70 (Dick has replaced this one with the Meade GEM
4504/114EQ. But the firmware is from the LXD-55 Telescopes. I assume
that you have downloaded ver23Eb with a DS telescope? That`s why the new
GEM code doesn`t show up.

2) Download ver23Eb with an ETX Model.
The following Telescope Models will be available: ETX90, ETX105, ETX125,
LX90, LXD55 127Ach., LXD55 152 Ach., LXD 6 New., LXD 8 New., LXD 10 New.

I have tried the new GEM software with my Vixen SP mount (equipped with
DS motors and Autostar controller) - it WORKS!!

And the best thing:  Dick will update his patch ( all telescope models
will be available  -thank`s for that Dick) - have a look at his readme
text in patch v23b4!  What would we do without him?

Peter Wallner

Subject:	Re: questions on two star align
Sent:	Tuesday, January 22, 2002 22:17:53
I had a thought about this and testing it with Starry Night does have
the above effect. We are only a few days into the new year. If you
entered the date and time correctly except for the year, entering 2001
instead of 2002, the stars would be in almost the same place where as
the Moon would be below the horizon. Perhaps this simple slip is causing
the problem?
Raymond Barbour
South Africa
Mike here: Excellent thought!


Sent:	Wednesday, January 23, 2002 10:22:39
Been reading about the problem(s) regarding the Autostar going 180
degrees off of its targets. Not too long ago I had the same problem. I
have had my scope and Autostar since they first came out. I have used
v1.0c, 1.3c, and one of the 2.2's with no problems. Then one day it just
decided that everything was 180 degrees about face. No clue as to the
source of the problem...time off? location off? whatever off? rhyme
or reason. So, I upgraded to the lastest version 2.2ek, and tried again.
No change!! What is going on here? My next move was to do a complete
reset. After that everything was back to normal. So, for anyone
experiencing this mystery error, just do a reset and start from scratch
(train drives, etc.). It should clear things up.

Jeff/Optiques Photographic

Subject:	polar reversed?
Sent:	Tuesday, January 22, 2002 19:48:05
From: (Trevor Cox)
I have just found your web site and what a feast for a new = person to
astronomy. I live in Bendigo Australia and have a etx90ec = (what a
telescope) with autostar. The problem is when I polar aligned it = on
the meade field tripod and programed it to align it slewed right and =
pointed to the ground instead of finding sirius. All the data entry is =
correct. I spoke to the dealer and he thinks it is the autostar and is =
getting a replacement to try. Has any one else in Australia had this =
Kind regards Trevor
Mike here: Have you tried Alt/Az mounting? (Don't forget to switch the mounting mode in the Autostar.)
Subject:	Re: questions on two star align
Sent:	Tuesday, January 22, 2002 9:42:07
From: (Jenny Mehlenbeck)
Thanks for always answering.  I do appreciate it.

I am really having trouble with this telescope.   (ETX 70 AT) Had the
first clear night in weeks last night.  I cannot get this thing to align
to anything!

I do plan to bring it to the shop where I bought it and let him play for
a few days.  If nothing more, the plug where the controler goes is
loose.  It often disconnects while turning.

I think it's brain dead as well but perhaps I'm just doing something
wrong here.

OK,   I DO have the scope level, at 0, and pointing north.  (Even got a
compus for this just to be sure.)  I have date, location (within 12 mi.)

Lets stop right here.  There are three sets of two digits in the time
setting.  I would assume hour, minutes and seconds.  Right????  With
three clocks in the house all with differant times on them, I don't care
about seconds and a few minutes off shouldn't make all that much
differance right????  So why, with date, location and time to within a
few minutes when I ask the scope to "go to" the moon, which is straight
overhead, does it tell me it's below the horizon?  Daaa, I'm not in

I later realized that I had daylight savings time to yes,  should be no.
Again, one hour the moon doesn't go from below the horizon to straight
up. Believe me I wen't through the process many times.  Each with
slightly differant results.

Later, I tried the two, then the one star align.  I send it looking for
Betalgeuse.  It scewes way off in totally the wrong direction.  FINE! SO
I manually get it on target, then hit "enter."  Then go find Bellatrix. 
Not all that far away right?  Again, this dumb thing scewes way off to
who knows where.  Again, I set it manually and hit enter.  "alignment
complete."  Uh ha.  So find the moon and away we go.  AT least it wasn't
pointing to the ground but it wasn't even in the same quadrant of sky
that's for sure. SO... go find Betalgeuse.  It should know that at least
and it still can't even find the one I just set it to.

So, can you see anything I'm doing wrong here?  Some common beginner
mistake I am missing?  or do I have a mental brain dead computer in my

This got long winded I know.  Sorry.  Looks like a clear night again and
I really hoped to see Jupiter or Saturn for the first time ever through
a scope.  Very frusterating.

Thanks in advance.
Mike here: Glad you corrected the Daylight time setting. And keep in mind that Magnetic North may not be the same as True North in some locations on the Earth (up to about 20 degrees difference). But like you say, none of this should have the Moon "below the horizon" when it is straight up. That would require the longitude to be off by 180 degrees (try changing the sign).


Your last sentance is confusing.    ???
> (try changing the sign).
What sign?

I don't know but I think this thing is messed up.  I tried setting it at
least a dozen times.  Same time, same date, same location.  Why would
the moon be below horizon one time and have the telescope scew way up
and towards the west the next?  It's just screwey.

Unfortunately I just watched the weather and clouds clouds...... Nuts!
I'm going to let the hobby shop guy have this for awhile like he asked. 
He knows a ton about this stuff.  Maybe if there is a break he can fool
with it.
Mike here: My thought was that your site's longitude is 180 degrees off (a plus sign or a minus sign when it should be the other sign; or East vs West longitude). But in rethinking it, if the alignment stars are slewed to correctly then the Moon shouldn't be below the horizon when it is not. So, yes, perhaps something is corrupted.
Subject:	Re: altitude problem
Sent:	Tuesday, January 22, 2002 6:10:38
From: (
Things did not go well. I down loaded the latest version, trained the
drives which came out great the second time I tried everything came to
within a couple of minutes of a degree. Slewing  in a 360 degree circle
came to within 3 minutes of perfect. Then I slewed up and down to about
88 degrees of elevation and down to -15 then up to where I was centered
on the object and came within 4 minutes of a degree. Then I set a few
landmarks and did a goto to each one and they were within a few minutes
of a degree. Last night I tried  tracking it took me four times to try
to get it to work properly. It was not very accurate on the guide stars
but said the alignment was good so I slewed to orions bright stars and
finally tried to track rigel it took about five minutes for it to random
slew. Each time I realigned it seemed to get better my final straw was I
was looking at M42 and then slewed to Castor and wasn't even it the
finder scope at least 25 degrees of elevation off . It also would move
in the horizontal plane when I would slew down. I don't know how far it
would want to slew that way but I would stop after it left the field of
view in a 26 mm eyepiece. The other problem is the azimuth percent
setting I can set it to 75% and still get the same movement if I were to
set it to 15%. When Clay says you should see movement within 3 seconds I
might see movement in 8 or 10 seconds. At all amounts of  %'s. I took of
the bottom and watched the gears move and at 15% the big shaft the
actually moves the scope was turning within the three seconds as
decribed by Clay. What would cause it to do that? So I guess I will send
it off to Meade tomorrow. My question is this why after a year and a
half of owning the scope did it all of a sudden decided to do this? And
what does meade do to the scope to fix it? Thanks for all the help
Mike here: Personally, I NEVER play with the percents and have NEVER had a problem with the latest Autostar ROMs.
Subject:	Re: re: Motor Unit Fault
Sent:	Monday, January 21, 2002 18:22:26
I though I should update you on the motor fault problem I have been
having. This last week I was away from my home traveling to New Orleans
on business so I did not get to work the problem until this weekend. I
had received the 505 cable package while I was gone.

Here is what I have done. >  Installed the Starry Night.    I think this
should be a big help to me in learning my way around skies and planning
my viewing each  night.

>  Downloaded the new version of the of ASU program from Meade's web
site and followed the update procedure for the 23e version of ASP and
updated the ASC. I did a ASC reset before updating. I calibrated and
trained the motors.

>  Went through the ASC init process putting in my location "Troutdale
Va (36 40.1' latitude and 81 25' longitude), date, etc.

>  Set the scope to home position and tried to aligned the scope.

>  Had the same motor problem "Motor Unit Fault"  At this point I
believed the problem was with the motor controls that operated the
vertical positioning.

>  I ran some test and found: The vertical motor would only run at full
speed. The motor would stop as if binding but there was no bind. The
motor sounded as if it the load on it was changing.

>  I took the plunge and disassembled the cover on the fork arm where
the vertical motor is located. As you have noted in other suggestions
much to much grease, I had foreign material in the gears, and grease was
on the light source. I also found that the circuit card was not secure
in its mount. As you know, if the card can move and/or the light is
blocked then the circuit can not sense the encoder movement correctly
and will not be able to count the ticks. After cleaning, setting the
card and reassembling the problem was fixed!!!    I suppose the card
came lose during shipment as it is not secured very tightly in it's

10. I now can align with out motor faults.

I now await the next clear night for my first viewing.

New issue!!!!   I now have found that the ASC tells me that it can not
find a "Guided Tour".  Did the "standard tours" get erased while down
loading the new version of ASP???? If they did how do I reload them. I
don't remember seeing anything about this.

Thanks for the help and insight as to the mechanical operation of the
scope. The discussion of the Calibration, Training, Percentage help
point me to the gremlins causing my problem. I am sure updating the ACP
to 23e will avoid many of the standard issues with these scopes.

Thanks, King

King Spainhour
Mainline Information Systems
793 Rocky Hollow Rd.
Troutdale, Va. 24378
Mike here: I just checked my 2.3Eb and I still have the three default tours.
Subject:	LXD55 Support on Autostar
Sent:	Monday, January 21, 2002 9:21:29
From: (Rose,John)
Are you aware of any way to get the Autostar to list the LXD55 family in
the range of available scopes after updating to 23Eb so that access to a
GEM mount set-up can be obtained.

I have tried both a normal and a safe download with no success.
Internally 23Eb seems to support 21 scopes but on the Autostar only 10
are listed (DS & ETX).

Any Ideas

John Rose

Subject:	New SAO test for Autostar model
Sent:	Saturday, January 19, 2002 12:09:06
From: (Richard Seymour)
Since Meade did a massive update to the SAO star database in the Autostar,
the -new- way to tell if you have a 495 or 497 is to try 
  Object > Star > SAO Catalog > 162 [enter]

If it has that star in its database, it's programmed as a 497.

That test will work for firmware vrsions 21E(anything) through 23eB.

(my previous test, SAO 22, is no longer in the database as of 23eA)

have fun
(and you can upgrade a 495 to 497-hood by using Meade's Updater at:  )
Mike here: There is a #497 "as purchased" and a #497 "as upgraded from a #495". So running the test just checks whether the #495 has an OLD ROM or has been updated, right?


A 497 is a 497 is a 497, and has 30,000 objects since v21E(anything)
 (the older 14,000-object multi-lingual versions falls into a mid-ground
 crack... i don't know if it has SAO 162). 

A 495 (in my parlance) has 1,400 objects and refuses to operate

Meade has sold v22eR 495's (so current ROMs, but still with those two

So "old" and "new" could be confusing. And still ambiguous.

495 programming would still refuse to be a Clone-recipient from a 497.

have fun

Subject:	Backwards star tracking in the southern hemisphere?
Sent:	Thursday, January 17, 2002 12:42:04
From: (Matias Petrella)
I live in the southern hemisphere and I'm having a *very* hard time
trying to get my Autostar to "track" (not "find") the stars. After
successfully two-star aligning my ETX-125, and GOTO any star, the ETX
will point to it with proper accuracy (well... almost), but the
subsequent tracking is worst than bad, to the extent that it 'tracks'
the stars backwards!!

What I wrote above is fact, and I'm the kind of person that double,
triple, and multiple-check things before submitting a post. I'm very
careful with the settings in my Autostar and: my location is properly
set, the time is OK, the tracking rate is set to Sideral, this happens
both in polar and alt/az modes, everything seems fine. I even downloaded
version 22er over the previous 2.0g. I would like to have some feedback
from actual southern observers.

Besides, I would like to ask if someone has any idea of the meaning of
some undocumented features of the Autostar, such as the meaning of the
numbers to be set in "Custom Tracking rate", and other numbers such as
the % and rates of Alt/Az movements (what do these numbers mean??)

Thanks again for mantaining this wonderful site!

From: (Richard Seymour)

You are -cruel- to me!
>  For instance, although it finds the stars with some accuracy, I can't get mine to
> correctly track them (in fact, it tracks them in the opposite direction! 

To give only that hint!!!
Please supply model of telescope ("ETX" is very broad), type of mount
date/time/location (so i can duplicate your situation), and example targets
which demonstrate the problem (below (nearer the ground) than the pole?
south facing?)  Thank you for providing the version (22eR) number... that helps.

There was a bug involving slewing at speed 8, (but only if you have ratio values 
higher than 3) which is corrected in the -current- version 23eB.
  (note we are now at twenty three, not twenty two).

I have -not- heard of your problem in -any- posting from south of the equator.
And i think i would have heard from both South America and (loudly) from

As i write this, i have told my ETX90, v23eB, Alt/Az, that it is in Buenos
and it is "tracking" Canopus at 8pm 14-jan-2002.  And it is moving east-to-west,
as it should.  (Easy Align chose Sirius and Canopus).
I have now switched to v22eT to cross-compare.  It is also tracking properly.
I just swung to a random northern target (Betelgeuse) .. and tracking is still
proper.  I am verifying the direction of travel with both the Alt/Az readout
(see below) and taped markers on the ETX90's base.
I have now (while assembling the list of S.A. people) run in Polar mode
with v22eT (and 22eT and 22eR are very similar).. and it is tracking properly
for both Fomalhaut (Piscis Austrinus)  and Alpha Ara ("below" the pole).
(Easy Align was Sirius and Fomalhaut).  23eB was also correctly tracking.
So i am sorry to say i -cannot- duplicate your symptoms.

Are you sure you are not seeing "rubber banding"? Where the telescope goes
backwards when you release the buttons due to loose training?
You would have to let it "track" for 5 minutes (without touching buttons)
to check which way the -tracking- is going, instead of just incorrect 
backlash correction.

Another way to verify or check what is happening is to let the telescope settle
into tracking, and then activate the Status display (hold MODE for 3 seconds,
release).  Sdroll down to the Alt/Az readout.  For Canopus at 8pm (not Daylight
 time) in Buenoes Aires, the Alt -and- Az should be slowly increasing.
(Alt faster than Az).  For stars north of your location, the Az should be

Mike also forwarded your message to him, which had the additional question:
> Besides, I would like to ask if someone has any idea of the meaning of 
> some undocumented features of the Autostar, such as the meaning of the 
> numbers to be set in "Custom Tracking rate",

The Custom Tracking rate is the percentage difference from sidereal rate.
So Lunar Rate is 3.5% slower than sideral. 
The value you use is tenths-of-percents, so that shows as "-35" in Custom.

> and other numbers such as the % and rates of Alt/Az movements (what do these
> numbers mean??)

Percents are somewhat described in my posting:

But that does -not- answer "percent of what?" perhaps "percent of too much".

> I read in one of your postings that you mantain regular contact with Southern
>  hemisphere owners of ETX telescopes and, if you don't mind, being an owner
> myself I would like to contact some of them.

I am sorry to admit that i do not maintain regular -contact-, but i do retain
addresses of people near Buenos Aires ("near" is a very wide word...) .

Here are some South American users (not all ETX90).

Phillippe in Mendoza:  (DS-114)

Leonardo Sinamon  in Hurlingham, Buenos Aires:  
Leonardo Gabriel Sinamon (

Fernando Margueirat  ( )
 Buenos Aires, Argentina

Nestor  Russaz.

Marcelo Peralta (    (ETX90ec)

y (posiblemente) (Haroldo Level)   Venezuela

and (i do not have the name for:)
in Uruguay...

good luck

Subject:	Starfinder 494
Sent:	Thursday, January 17, 2002 10:58:51
From: (Margaret Meakin)
My Meade 4504 telescope came with a Starfinder (type Autostar 494 inside
handset). It has stopped displaying any text on the LED and there is no
red background light although it powers up..

It stopped working whilst "initialising". All batteries, cables and
circuits are O.K.

Is there a solutionto my problem?

Kind regards.

Mike here: Did this happen during a cold night? The Autostar display is very sensitive to low temps. OR did this happen because the Autostar became too warm? The Autostar display is very sensitive to high temperatures. If cold was the problem, just warming it back up brings the display back. Unfortunately, if the Autostar is cooked, it really could be cooked and you may need a new one (contact your dealer or Meade).


The Starfinder was indoors when I was setting up and was not subject to
temperature extremes.

When I connect it up now the motors intermittently whir into life
(although there is no text on the LED panel) and the red background
light occasionally flickers on/off. Is it possible that the 494 memory
could have been deleted?

Is there a cure or is it curtains for my Starfinder?
Mike here: It may or may not be curtains for it. If you have the #506 cable you could run the ASU 3.0 on it (even though there is no ROM update for the #494). Just having it talk to the Autostar can cure some ills. But I really suspect something is wrong with the hardware of the display and you won't be able to fix it with software. Contact Meade or your dealer.
Subject:	Precision alignment
Sent:	Thursday, January 17, 2002 7:08:47
From: (Julian Garrett)
I know this is probablly covered somewhere but I have not been able to
find it...Is there any way I can get my scope (ETX-70) to "remember"
minor corrections??? I think it is probably under "High Precision
Alignment" After about a month of using the scope I am having no problem
finding and aligning, but if I GOTO and make minor correction to center
my target in the eyepiece, I have to do the same thing for the next
GOTO.. If I use the "High Precision" method will it remember my
correction or will there always be "some" corrections that I will have
to put in to center??? Also on "red-dot" finder scopes, I found a
Crossman model that has a 2 position brightness level switch, so it is
not necessary to have to add a pot. Also reducing the resistor by even a
small amount causes the LED to not come on at all..

Thanks, Julian 
Julian Garrett
Mike here: I think you are looking for the SYNC function. Quoting from an older message from Dick Seymour:
SYNC is done by simply: [goto] a target, 
wait for the beep (and any after-beep motion).
press-and-hold [enter] for more than 2 seconds.
it'll beep and ask for you to Center the object.
slew to do so.
press [enter] again.  It'll beep and be SYNCed.

Subject:	Autostar Video
Sent:	Thursday, January 17, 2002 4:48:12
Many hobbies have gotten so technical that video "How-To's" have become
necessary.  Have you ever considered doing an Autostar how to, or has it
become so reliable you feel that's pointless?

Based on what you said to me recently & past experience with an
extremely heavy Meade refractor, I am currently upgrading to an
ETX-90EC, rather than the 125, hoping the 90 will be ready to use on a
minute's notice.

Once more, countless thanks for your invaluable website!
Mike Isenberg
Mike here: Yes, I have planned on doing that but just haven't had time. There are a couple of visual Autostar tutorials on the Tutorials page.
Subject:	Updating Autostar with a Mac
Sent:	Thursday, January 17, 2002 3:55:12
From: (Jim Wilkins)
In OS X (10.1.2) did you disable the keyspan port in Networks?  You have
to do that or VPC gets upset.

Mike here: Well, that cured the Window98 "port in use" error. Now to try the update again at some point. Thanks.


From: (Stan Glaser)
Thanks for that write-up. I still haven't performed the 2.3Eb update as
yet, but this sounds typical for a number of Autostar updates that I've
tried to perform. My G4/450 has yet to be updated to OS X, but my wife
just got an iBook 600 and I've loaded VPC 4.0 on that, but haven't tried
anything from that machine either. I know VPC 5.0 will run under OS X,
but I don't have that, either. And I still don't have the OS X drivers
for the Keyspan USB-to-serial adapter (gee, I don't have a lot of stuff,
do I?).

I think when I do try the 2.3Eb update that I'll stick to VPC 4.0 under
OS 9 -- it's worked on at least two earlier updates under that
configuration, and I don't see the need to take any chances. But thanks
for the heads up notice.

Stan Glaser

Subject:	re:  Motor Unit Fault
Sent:	Wednesday, January 16, 2002 22:43:13
From: (Richard Seymour)
i saw your note on Mike's site, and his response left out one -critical-
step, which by itself might cure your Faults ... 

Perform a Setup > Telescope > CALIBRATE  (enter)  operation!

it takes 5 seconds, and can cure Motor Unit Faults (which aren't dead-battery
or jammed mechanisms) .

You should also do one after afirmware update.

If you -do- update your firmware, set your Autostar in 
 Setup> Download [enter][enter]   
before connecting with the Program (after all power-up steps).

have fun

Subject:	re: autostar lock-up
Sent:	Wednesday, January 16, 2002 22:12:09
From: (Richard Seymour)
i saw your note on Mike's site...

a question: what VERSION is in the Autostar?

You reach the -real- version number by using the scroll key
to reach the SETUP > Statistics   menu item, press [enter] and
scroll up once.

i haven't heard of a specific Mars problem in any recent (1.3 and
newer) versions.

As Mike suggested, a (simple?) firmware reload will probably fix it.

good luck

Subject:	response to "Altitude problem," January 15
Sent:	Wednesday, January 16, 2002 21:16:19
From: (Bill Collins)
Brian, I think you have experienced the dreaded "random slewing" that
many ETX owners have cursed. Once in a while the telescope drive will
just take off -- usually in altitude -- for no apparent reason. Meade
claims to have corrected this problem in recent scopes, and I understand
that you can ship yours back to Meade and they'll fix it.

Bill Collins
From: (
Mike I did train the drives once the first time I down loaded to the
autostar and twice the second time I down loaded to the autostar. I did
reset the autostar after each time I trained the drives. I went to the
meade site and I thought I down loaded the latest version I guess not I
will down load 2.3eb. The reason I trained so much is it wasn't tracking
in altitude properly. I made sure all the info in the autostar is for
the model I have as per Mr. Sherrod's instructions. I will up date you
as to what happens next. You shouldn't worry about the delays you may
have in responding if it takes 3000 pages to down load your site I
believe a delay is to be expected  that is a lot of responses. Thanks

Subject:	EXT 125 problems
Sent:	Wednesday, January 16, 2002 19:39:16
From: (John Clendinneng)
I received my replacement ext125 just before Christmas but have only had
2 chances to use it due to very cloudy weather.

The first time I used it the finder broke, the focuser assembly became
detached from the finder. I called meade to ask them if I could glue it
back on, they said yes and they also replaced the finder with a new one
no questions asked.

so now I have 2 functional finders but I am having a problem with the
easy align on the autostar.

Now when I received my first scope (the one with the r.a. lock that
would not disengage) I had absolutely no problem performing the easy
align, it worked every time.

I performed the test drives procedure and the alt and dec calibration
procedures prior to using the scope and then when I went to use it with
easy align the star that it was searching for was no were near the field
of view of the finder both the r.a. and the dec are off.   So before
using the scope again I reset the auto star and re-initialized it.

I tried again tonight and still no luck.

when I set up the scope I put in the home position pointing to magnetic
north, level the base, level the ota and input the time from the us
atomic clock web site.

I am aware that magnetic north is not accurate but it worked fine with
the first scope.  I even tried setting it up at magnetic north -10
degrees east, which from my location (Montreal Canada) should be pretty
close to true north.

any suggestion would be greatly appreciated

Regards, John Clendinneng
Mike here: Check the telescope model in the Autostar as well as the date/time/location settings. Don't forget the Daylight Savings setting; that's a simple one to miss and results in 15 degree errors in initial pointing at the alignment stars. You said the stars were "off" but not by how much so this could be the source of the error. As you noted, Magnetic North is not correct to use; even though you tried to compensate for it, could you have some magnetic sources affecting the compass? Can you see Polaris or otherwise determine True North (like from street maps)? As to the other alignment tips, see the Autostar Information page.


The telescope model is set to ext125, location is Montreal and the time
entered was accurate to 10 seconds.  (I had my wife tell it to me from
inside) daylight saving was set to no. as for the compass its the same
one I used before and the exact same procedure never had a problem with
the other scope.

as for the pointing accuracy it was off about 15 degrees in r.a. and 10
degrees in dec. I am also using a ac adapter because the batteries will
not work in minus 12 degrees after the scope cools down.  could it be
the cold?

I have re trained my motors (indoors)using 300x magnification and the
finder is spot on at 300x.  I will try again if we ever get a clear

Regards, John Clendinneng
Mike here: Well, it could be the temperature, especially if you trained when it was significantly warmer. Also, the grease gets stiffer with the low temps, which can cause some problems.
Subject:	altitude problem
Sent:	Tuesday, January 15, 2002 13:38:22
From: (
I down loaded the latest version of  autostar 2.2 eh and did the
training as per Mr. Sherrod's instructions. After training I tested it
again as per Mr. Sherrod's latest instructions, that is slew in all four
directions and up or down in each direction. I was never off by more
than a few minutes of a degree. I also slewed a 360 degree circle and
was off by 4 minutes. Then I tried it out that night again as per Mr.
Sherrod's instructions to let it track for a few hours. I trained it on
Rigel for the first 20 minutes it was perfect, I was checking it every
five minutes. When I checked it at 25 minutes Rigel was nowhere to be
found. It wasn't even in the finder scope in five minutes it moved that
far after being perfect for the first 20 minutes. I decided to down load
the autostar again and do it all over again. I tested it twice for a
comparison, wrote all the figures down this time and again wasn't off by
more than a few minutes. Tried it again that night and trained it on
Rigel again and this time it didn't even track for a couple of minutes
before it was out of the finder scope. Slewing around the sky it was off
by 30 to 40 minutes. always in the altitude. If I would stop on a object
for a few minutes I had to adjust it. All the tests and viewing were
done in the same location with the 26mm eyepiece. My question is what
could have happened? And do you or Mr. Sherrod have any idea as to why
it did this and a possible solution. I have done the tune up that Mr.
Sherrod suggested to do about a year and a half ago. I took the bottom
off and checked for and problems and found none I am waiting to take the
OTA out of the mount for a suggestion from either of you.

Thanks for the help in advance, I don't know what I would do if it
wasn't for you guys.

Mike here: Couple of points: The current version on Meade's site is 2.3Eb, which is downloaded by using the Autostar Update Client 3.0. Second, after updating the ROM in the Autostar you MUST retrain the drives. You didn't mention if you did that. Remember, the better the TRAINing the more accurate the tracking. At any rate, I would suggest retraining and see what happens. Also, be certain the scope model in the Autostar is correct before doing the TRAIN DRIVES.
Subject:	RE: See the (new) stars...
Sent:	Monday, January 14, 2002 18:40:59
From: (Bob Rose)
To: (Richard Seymour)
The charts look great. Meade's fixing "some database errors" gets rid of
the old "C" and spreads the SAO stars out where they can be useful.

bob rose

Subject:	495 with ETX-70AT
Sent:	Monday, January 14, 2002 18:13:09
From: (Bo Byrd)
I have a 495 that I bought to replace the 494 for my EXT-70AT
When I boot up it says:

c(99) Meade [1.2]

I made the 505 cable and pinned it out and its wired correctly according
to all the wiring diagrams on your site. I've done a lot of RS-232 stuff
before so Im 100% sure I've got it wired up right.  But I cant get the
ASU program that I just downloaded from Meade to detect the damn thing. 
I've reset it and tried everything I know.  How do I upgrade this thing
to work as a 497???  Is my 495 a real old model with real old code that
I have to do an intermediate upgrade or something?


P.S.  I forgot to mention that I'm using WindowsXP. I've also tried
typing characters in a hyperterm at 9600-N-8-1-NoFlowControl and cant
seem to get any activity there either.

Mike here: It should have worked (assuming the cable is OK). You should have been able to go from 1.2 to 2.3Eb but maybe that was too old for the ASU 3.0 application and you'll need to go through the ASU 2.4 to update to 2.1ek and then use ASU 3.0 to get to 2.3Eb. The older versions are in the "Autostar Software Archive" linked from the Autostar Information page on my ETX Site.


Well I found out what the deal was.  I guess with the real old s/w the
unit was running you manually have to put the autostar into download
mode through the autostar menu.  I did that and was able to upgrade it
to 2.3Eb.  Now I don't have to manually do anything to the autostar when
I want to do things to it with ASU3.0 I guess they added that
functionality as a feature for us. Well I got it up and running...


Subject:	Richard Seymour's Post
Sent:	Monday, January 14, 2002 7:46:30
From: (Jamie Hawley)
Thanks Mike.  I followed Richard Seymour's post: "Autostar Updater...a
cookbook approach" and it looks like I successfully downloaded the new
2.3Eb as well as several tours, satellite data, comet data...  Richard
is truly an asset for those of us who are somewhat computer illiterate,
it was a wonderful post.

Best Regards,

Jamie Hawley

-----Original Message-----
>As to the Autostar download, it is really fairly straightforward
>if you have a good internet connection.  Just click to update the
>Autostar; it will ask if you want to get the file from the Internet or
>your local hard drive.  From there everything is automatic (I just did
>the ASU 3.0 update to 2.3Eb this morning).

Subject:	Autostar freeze-up
Sent:	Monday, January 14, 2002 1:14:45
From: (Bill Weilbacher)
First of all, great site.

I am a new puchaser of a ETX 90.  I ordered an optional autostar
controller and went through the alignment procedure.  Everything  worked
out fine. Hit GOTO, selected Jupiter, and there she was.  Went to
Saturn.  Everything was great.  Then hit Mars and the autostar locked
up.  Would not respond to any key commands.  I shut it off and tried
again and this time it locked up in the middle of the alignment
procedure. It now does it every time I use it. Any ideas??

Mike here: Check your batteries and the connections. If you haven't done it already, you should select the ETX-90 from the telescope menu and TRAIN the drives. Check the version number; if not the current version and you have (or can make) the necessary #505 cable, you should update to 2.3Eb.
Subject:	Rubber Banding
Sent:	Sunday, January 13, 2002 15:41:19
I would just like to repeat a piece of advice which has been given on
your site before and which I found extremely useful.

I have an ETX 90EC and an Autostar loaded with version 2.0, which was
suffering from what I now know is termed "rubber banding". After
performing a GOTO, if I tried to centre the object in the FOV, the scope
would track back to the original position. I almost took it back for a

The advice on your site (thanks to whoever wrote it - I can't seem to
find it again) was to train the motors using Polaris - i.e. something
not moving but high up in the sky - higher than the telegraph pole
recommended by Meade.

Bingo! 100% accuracy now, without having to upgrade the handset.

I hope this will help anyone who got a scope for Xmas or bought one in
the sales and is suffering from the same problem. I would never have
thought that such a simple thing could make such a big difference.

Thanks for the site Mike. I will be buying a copy of your book in

Paul Crofts
Somerset UK 
Mike here: Yep, that is a good technique which I use often after updating the Autostar ROM and which I'll have to do again now that I've updated to the new 2.3Eb.
Subject:	Re: 23eA... first bug (and workaround) found...
Sent:	Sunday, January 13, 2002 12:00:45
From: (Richard Seymour)
The Honorable Mike Weasner wrote:

> Seems like this was fixed in 2.3Eb.  I scrolled to OFF and it seems to
> have stayed that way.

Correct... there are only 5 bytes different 'twixt 23eA and 23eB...
one in the checksum, two instances of the "eA" vs. "eB", and two
"branch if equal" changed to "branch if NOT equal" ...
 one in "Sun Warning", one in "Getting Started"...

have fun...

Subject:	Autostar version
Sent:	Sunday, January 13, 2002 6:03:13
From: (Johan Gadenius)
On Meade's homepage the latest version for the Autostar is indicated as
23Eb. On your own homepage it is 23Ea. Fair enough.. they have updated
again. But now to the question: I have earlier a version calle 23Et.
That sounds pretty much newer to me. First come a, then b and verrrry
late comes t. Should I update to Eb anyway?


Johan Gadenius
Sollentuna - Sweden.
Mike here: I only put older versions on the ETX Site. Meade always has the current one. And yes, 2.3Et is newer than what you have since I suspect you really have 2.2Et, not 2.3Et. As to updating, there doesn't appear to be any new functionality for ETX or DS scopes. Yes, some database errors seem to have been fixed but not clear whether those errors would have bothered most small telescope users.
Subject:	Autostar with 30,000 objects?
Sent:	Saturday, January 12, 2002 5:11:15
From: (Jim Gilliland)
I note that the Shutan Camera site has an Autostar 497 listing that
includes this description: "Now with 30,000 objects!".  Does that mean
that Meade is now selling an Autostar with twice as much internal
storage, or has the 497 always had the capability to store this much
data?  In other words, can I just download an update to get this new
database, or does it require a newer physical device?
Mike here: Back in 2.0 the Autostar ROM was updated (via software) to include the same database that was available for the LX90 8". That brought the total up from some 14,000 to over 30,000 for the #497 Autostar. You can update using the Autostar Updater page on Meade's site if you have the #505 cable (assuming you have a #495 or #497 Autostar).
Subject:	ETX 125 control
Sent:	Friday, January 11, 2002 23:54:31
From: (Keen Young)
I looked through your pages, but I couldn't find anything related to
this. Is it possible to run the ETX125 with a computer but no Autostar
hand controlller?

Mike here: No. The Autostar is required.
Subject:	make that 23eB  (or 23Eb, they way they like to do...)
Sent:	Friday, January 11, 2002 11:26:13
From: (Richard Seymour)
an update to the update was issued this morning...


Subject:	23eA... first bug (and workaround) found...
Sent:	Thursday, January 10, 2002 21:19:29
From: (Richard Seymour)
It appears you cannot turn the Sun Warning (or Getting Started message)

well, you can... when, under Utilities / Sun Warning you're seeing
">ON",  press [enter] if you want it to turn OFF.

The next time you visit that screen, or cycle power, you'll now find
it's ">OFF"

stay tuned...

Subject:	North or Polaris?
Sent:	Thursday, January 10, 2002 20:43:12
From: (Douglas Schlosser)
I have been looking over your site for several hours today. By the way
great site !!!!!!!

I am very new to astronomy and am kind of intimidated about asking a
really stupid question to news groups. I am having some difficulty
getting started. I have had me ETX-90EC since last year and have not
used it very much until now. I just got the Deluxe tripod and the
Autostar  for Christmas. Well here is my stupid question;

Here is what I got off your website;
1. Position the whole ETX and tripod system with the ETX control panel
on the west side. This doesn't have to be exactly due West but should be
as close as possible.
2. Level the ETX base. Again, this doesn't have to be exactly level (I
usually just eyeball this).
3. Unlock the altitude axis and position the ETX Optical Tube Assembly
(OTA) to 0 degrees. The ETX OTA should be parallel to the ETX base.
Relock the axis. If the scale is off it can be adjusted by loosening the
knob, rotating the scale, and retightening the knob.
4. Loosen the azimuth lever and rotate the ETX OTA counterclockwise
until you hit the stop. Counterclockwise means moving it from (for
example) South to East to North to West.
5. Now rotate the ETX OTA clockwise back to the North. This is a
rotation of approximately 120 degrees or from pointing towards the
Southwest through West to North.
6. Continue with the Autostar Alt/Az initialization and alignment.

The part that confuses me is #5. Do I rotate the telescope and position
Polaris in the center of the telescope or do I just get a compass and
rotate the telescope and tripod until the pointer points north???

Any help you could give me would be greatly appreciated.

Thanks . Doug
Mike here: You have all the steps correct but you are confusing North with the star Polaris. This is easy to do. Polaris, commonly called the "North Star" shows you where True North is (within about a degree) along the horizon. And in Altitude/Azimuth telescope mounting you want the HOME position pointed to 0 degrees True North. If you are Polar (also known as "equatorial") mounted then you point the telescope tube AT Polaris (for most purposes this is accurate enough). Hope this helps.


Ok maybe I just not getting this, but how do I point the telescope to
true north in Alt/AZ or is this not important??
Mike here: Yep, it is important to point towards True North. If you can see Polaris, just find a point on the horizon that is directly below Polaris. Point the telescope at that.


Will do. Since I'm really green at this, I think I'll get a compass any
way. I should be able to check and make sure I'm not to far off.
Mike here: Keep in mind that Magnetic North and True North can differ from zero degrees to almost 20, depending upon where you live.


Thanks for the advise. I went out for my virgin run. Not to successful
with Autostar. However, I did look at some things in manual mode. I'll
keep working on it.

Thanks ... Doug

P.S. I have no idea what I was looking at.

Subject:	New Firmware!   v23Ea... LXD55 supported!
Sent:	Thursday, January 10, 2002 17:31:25
From: (Richard Seymour)
v23Ea has appeared on Meade's support website

It's the item dated 1/08/02 (funny, it wasn't there on the 9th)

It's about a half-megabyte ZIP file.

You'll need to have per-loaded the Autostar Updater
 (the Sept 2001 -dated item on that page) to load it.

The Autostar Updater is also capable of downloading the file for you.

-I- have not tested this file (yet).

The Meade page says that it provides support for the LXD55 series
(so it knows GEM mounts!)  and has "improved databases".

have fun

Subject:	494
Sent:	Wednesday, January 9, 2002 19:22:05
From: (dan walter)
i have( 2) 494s,  (1)is V10E1,the other is V11Ec.when i give same time
&date,ect...i get slighty different coordinates for moon &planets not
much but some???what i,m asking is ,without an update will they always
goto these targets or will they someday drift?i update my satelites
ect.will i have to update the moon someday.........just
Mike here: Yes, there is likely some difference in these two versions. Hopefully Meade will release an update before it gets seriously out of whack!
Subject:	Autostar and Starry Night
Sent:	Wednesday, January 9, 2002 18:37:51
From: (Bob Becker)
I am pretty new to this subject and am a little confused about using the
Autostar 497 along with my Meade 90EC and Starry Night.

When connected to the telescope, the Autostar functions perfectly;
finding all the correct locations.(Or at lease pretty close) When I
connect to the Laptop and try to run Starry Night, the ACP program loads
and everytime I try to go E it goes W...going W seems to go E.
North/South seem fine. As a result, whenever I try to slew to an object,
it goes exactly in the wrong direction. I start out pointing the
Telescope N and at "0" From where we live, Polaris is at a location
about 1/2 the way up from the horizon to straight up (Sorry for not
using the correct technical language) but every time I use Starry Night
and slew to Polaris, the scope winds up pointing straight up.

I AM CONFUSED...Mechanically all is fine...I must be missing something
in the setup of Starry Night. I have gone through all the documentation
and have been on several other sits looking for assistance.

Any ideas of what I am doing wrong? Please Help!!

Thanks, Bob
Mike here: Do you have the latest plugin for Starry Night (from the vendor)?


I had some success last night.  I aligned the autostar BEFORE I started
Starry Night and the ACP and I believe that made all the difference.  I
have not had a chance to check it outside yet but based on my indoor
testing, that seemed to resolve the issues.

Subject:	Autostar 494 question
Sent:	Wednesday, January 9, 2002 06:10:11
From: (Julian Garrett)
I just discovered your site and I think it is a wealth of information.
It will take me weeks to go thru it all. You have done an outstanging

I got an ETX-70AT for Christmas and so far so good, it is a lot more
that I expected to get out of it.. The only problem that I am having is
that I cannot read the second (scrolling) line on the display..The
letters appear to be doubled or all jumbled togather!!!! Is this a
problem that I should take up with Meade or is there some type of
adjustmet that a have not discovered yet??? This only occurs when it is

Thanks, Julian
Mike here: Are the letters scrolling by too fast? If so, you can adjust the speed with the up/down arrow keys. Otherwise, try a RESET from the Utilities menu.


Dang!!! That was fast!!!!  It appears that it may be scrolling too
fast...I will try that when I get home to-nite...
Thank you very much,  Julian
And this:
The scroll keys seemed to fix the problem, althought it is still a
little hard to read when it is scrolling...One of the first messages I
saw was was how to adjust the scroll speed, but I could not read it
untill I got it slowed down!!!

The first 3 nights I had it out, I was able to align it with no problem,
but last night it was about 9:00 before I got out. I never did get a
good alignment!!!! I think what happened is the first few times I went
out was right at dusk, so the only stars that were showing up were the
brighter ones so I did not have a problem picking the correct one.  Last
night there were so many visible I did not know which one to align on.
This is my first crack at star gazing and know very little about the
sky.. I know the manual says that the alignment star will be the
brightest one in the area, but I had a hard time discerning which one
was the brightest.... I know the scope was pointed North (by compass)
and was level (by bubble level).. What I would like to know , is there a
list of the alignment stars that the  Autostar uses, posted anywhere or
do I just have to scroll thru the list on the Autostar and write them
down?  What I would like to do is look at a particular star on a map
(Starry Night) before hand so I will have a better idea which one to
use...I'm a country boy, so I have a pretty good view from my backyard.
Just a few trees close in..
Thanks, Julian
Mike here: Yes, there is just what you need for aligning. See the "Alignment/High Precision/Star Charts" on the Observational Guides/References page.


Found it!!! Kept searching and found a database of alignment stars under
Autostar data...
Thanks, Julian

Subject:	Skipping alignment stars
Sent:	Tuesday, January 8, 2002 08:35:37
I know somewhere in the ETX-70 manual, or your website, I ran across the
command to use if one, or both stars used to align the scope is behind a
tree, or building. I cannot find it now. Will you point me in the right

Mike Isenberg
Decatur, Illinois
Mike here: Just hit the down (or up) scroll arrow on the Autostar to move to the next alignment star.


I found it later today, page 15, Thanks anyway. The more I read your
site, the better I like it!  My wife is really jazzed about the ETXs, I
made an offer today on a 125 listed on your site.

Subject:	etx60 at
Sent:	Tuesday, January 8, 2002 02:12:54
From: (alan & jenny neilson)
I have set up my new telescope and am unable to get it to GOTO the moon.
Tonight the moon set at 5pm and after I have done all the necessary set
up alignments, and then GOTO moon the scope starts looking for the moon
+about 19 deg. rising in the east this is at 9.30 pm what am I doing
wrong. have tried heaps of times, have reset a couple of times what do I
do next.

Alan Neilson  
Mike here: I'm confused. You said you were trying to GOTO to the Moon at 9:30pm but that the Moon had set at 5pm (which I haven't checked). Of course, the Autostar shouldn't "show" the Moon as in the Eastern sky at that time. As to what you may be doing wrong, have you tried to GOTO other objects and are they similarly off? Anyway, for alignment tips see the Autostar Information page.

Subject:	Your Intenet Site
Sent:	Sunday, January 6, 2002 17:26:50
From: (Matias Petrella)
This is just another "thank-you". I have an ETX-125 with Autostar but
had not the #505 cable and, frankly speaking, the 2.0g software embeded
with my Autostar had a lot of failures, especially in my area. I live in
the southern hemisphere and couldn't get my Autostar to point twice at
the same star with respectable accuracy. Add to that, the difficulty to
bring a #505 cable from the US and the associated cost (plus shipping!)

Now, thanks to your site, I built my own #505 and it works great, in
fact, I already updated my autostar version to 22er. However, I would
like to add something essential that is not said in other postings:

-First, the RS232 plug that fits into the Autostar hole is technically
called "RJ-9". It is *not* a modified RJ-11, nor a Meade proprietary
kind of plug. So, it's ridiculous to bother filing a RJ-11, and
incorrect to ask for a RJ-12. Just ask for a RJ-9 plug and you'll be on
the right way.

-Second, this is minor, but you can use a mouse cable to build your #505
(as I did). Proceed like this: if you have a mouse you no longer use,
cut its cable. You'll find that this cable has actually 4 conductors,
three of them are the onces needed to built the #505. For a Genius
mouse, each conductor has a different color, which correspond as follow:
  -Orange: Rx 
  -Green:  Tx
  -Blue:   Gnd
  -White:  (unused for #505)
So, you just need to go to a telephone store, and ask for a RJ-9 with
some inches of cable attached. Then, just connect each of the three
active conductors of the RJ-9 with the three active conductors of the
mouse cable and voil: the #505 is done and ready to shoot.

Thanks again for such a great site!!


Subject:	AS 494 help
Sent:	Sunday, January 6, 2002 16:31:19
From: (Gabriel Martinez)
I'm experiencing some very strange behavior from my astro-star.  When I
power it up, I get the "meade [11E] Autostar" screen followed by
"Sending Data".  I cannot seem to get it past this point.  Normally, I
see "initialization....". Have you seen this before?  Is there some sort
of reset that I can perform?

And from our resident expert:
From: (Richard Seymour)
Very strange...

Obviously your Autostar thinks it's in the "push" half of a
"Clone" operation.  (i can't tell if it's pushing data or
firmware, the message is the same).

Needless to say, It shouldn't do that.

What was the -last- thing you did the time -before- it
started doing this?  (were you using the Updater? A2.3?)
It's possible that a bad download could conceivably do this,
 but usually it gets further into things before it dies a 
  very confused death.

494's don't have "emergency flash load", so the hold-two-keys
during-power-up strategy won't help/work.

Most likely it's going to require a phone call to Meade's
800-number, and they'll simply mail you a new one. Free.

(if you wanted to put a -second- autostar at risk, you could
cable them together such that your autostar was able to -complete-
whatever nefarious plans it had in mind... but i really do NOT
recommend that...)

If you have a 506 cable set, you could try sending control-F
 to it to -try- and gain its attention, but even clearing an ongoing
data transmission in mid-stream takes a LOT of handshaking.
Another thing might be to try powering the Autostar either without
any telescope attached, or connected to a different one (in case
it's shorted wiring inside the telescope confusing it)

sorry... i can't think of a quick (nor slow) fix save calling Meade.

hmmm... maybe i shuld write a PC program which can act as if it
-were- the receiving end  of a Clone... that'd be amusing.
(i already have a "downloader", which can -ask- the 494 to spill its
 guts... but it cannot handle the 494 shouting at it unexpectedly)
From: (Gabriel Martinez)
Thank you both for your time and thoughts.  
I called the store I bought it from and they said they will replace it.

On a side note, do you think it would be worth upgrading to a 497?

Mike here: Upgrading could be worthwhile only if you plan to get a larger ETX someday. There are many more objects in the #497 than in the #494 but most of those extra ones will likely be beyond the capabilities of the ETX-60AT and ETX-70AT.


From: (Gabriel Martinez)
Actually, I have a DS2114 reflector.  It does come with the #494. Also,
I just got back from the store and exchanged it no problem. Everything
seems alright now.

Do you have any good recommendations for a CCD device, other than the
B&W one that came with it?

Mike here: Regarding a CCD device, check out the SAC CCD system (see the entry on the Astrophotography page).


From: (Richard Seymour)

> Do you have any good recommendations for a CCD device,
> other than the B&W one that came with it?

I have no direct experience in that area... the answers range -very-
widely (and wildly, price-wise)($40 to $5,000).
For starters.. the unit which came with the scope uses a CMOS,
not CCD, sensor... much less sensitive.  Much cheaper.

When i come across the yahoo Egroup link for imaging, i'll forward

have fun
And this:
From: (Richard Seymour)
> I called the store I bought it from and they said they will
> replace it.
That's very good ... many stores simply say: "Call Meade".

> On a side note, do you think it would be worth upgrading to a 497?

I saw Mike's answer, and mine is my usual one-size-fits-all:
"It depends"

The big differences between the 495/497 and your 494 are two-fold:
(1) the numeric keypad (handy for entering numbers, and instant
 control of speed, rather than pressing [speed] a number of times)
(2) the ability to use a simple 505 cable to talk to it from a PC.

If you have not purchased a 506 cable/converter for your 494,
a 495 (you can find them for $50) and a home-made 505 cable
will let you control the telescope from the Starry Night CD
which probably came with your scope. 
You will also be able to download firmare updates, and easily
enter satellite (and other) orbital data if connected to the PC.

But your telescope will work very well -without- moving up to a 495
or 497.  (the 495/497 are the -same-, only the programming differs).

If you do not -intend- to talk to your Autostar from your PC,
then a 495 or 497 won't necessarily be overkill, but may not
gain as much improved operation as the same money invested in
an additional eyepiece, or a Barlow, would provide.

I can't make a remote judgement of how your money is better spent...
perhaps you can easily afford -both- a 495/497 -and- a Barlow.
I don't know.  You'll have to make the judgement.

What i also don't know is your telescope *model*.

If you have the Meade 4504 or 114EQ-DH4 (both on German Equatorial
 Polar mounts), then a 495/497 currently will NOT work!
The programming currently does not know how to do "German Polar".
Once the LXD55 family is on the market, firmware will appear which
will be able to... but not for a month or two yet.

So you can see why it's hard to give a simple "yes" or "no".

have fun

Subject:	Help! Autostar/PC Comm Problem
Sent:	Sunday, January 6, 2002 9:06:12
From: (Jeff Ezell)
I was wondering if you could help me with a comm problem between my
EPX-125 Autostar controller and PC. I have a Model 497 controller and
made up an RS-232 cable using directions posted on your website. I've
tested the cable connection using a multimeter and shorting pins 2-3 to
check for an echo return on the screen (I'm running the hyperterm

An email on the Autostar site outlines a self-diagnostic procedure to
test RS-232 communications. This is done by shorting pins 2 and 3 and
turning on the Autostar. You're then prompted to press all buttons on
the controller in sequence. This test is completed succesfully.

At this point an error message occurs: "Pic failure V12 C001".

What is the significance of this message? Could this be the problem?
When I enter a control-F sequence, I get a symbol in response that looks
like an Ace symbol from a deck of cards. Entering the #: <command>
string has no reply from the autostar.

I've rebooted the machine, controller, and triple-checked all comm
settings. Any ideas?

BTW, your site is great! I received my ETX-125 for Xmas from my wife and
she told me how knowledgeable the salesman was about the product. I
walked in after perusing your website and knew a bit more than he did
about the product. He did however, know about your site.

Thanks again,

And from our resident Autostar expert:
From: (Richard Seymour)
> An email on the Autostar site outlines a self-diagnostic procedure to
> test RS-232 communications. 
Good guy!  He's done his homework!
> At this point an error message occurs: "Pic failure V12 C001".
> What is the significance of this message? Could this be the problem? 

That's an acceptable message to get in an in-the-field Autostar.
Not a problem (i get it, too).  It probably just means we're not
attached to a Meade diagnostic test bench. (i should amend the
test procedure posting to cover that message)

> When I enter a control-F sequence, I get a symbol in response that looks like an
> Ace symbol from a deck of cards. Entering the #:  string has no
> reply from the autostar.

Okey doke: i assume by "Ace" symbol, you really mean the spade (vs. hearts,
diamonds and clubs)... that's a valid symbol from a PC's character set...
I forget if it's character 0 or x80 (or 4/84)... not part of the ascii
set, but a leftover from Ye Olde Daze of the original IBM PC ...

Be SURE that hyperterm was set to 8-bit characters, one stop bit,
no parity, no flow control, 9600 baud.

Another -good- test is the current Meade Updater!  
Open it to "advanced functions" and click on "connect"
and (if successful) "retrieve data from handbox".
If either or both of those operations are sucessful, you've got it.

Be aware that miswiring/swapping pins 1+2 on the rj11 end of the home-build
cable can also cause confusing symptoms.. the "Ace" symbol could merely be
the PC reacting to the noise on the mis-wired line.  And that mis-wiring
would not show up by the "short pins" test.

If you use a voltmeter, the Autostar's pin 2 should be putting out
about negative 5 or 12 volts relative to pin 4 (using the Autostar's
rj11 jack for pinnage...).. at the PC end of the cable, that means
that pin 2 of the 9-pin connector should show -5 volts compared to
pin 7.

I see that some of the pinnage pages on Mike's site have pin 3 
of the RJ11 -also- tied to ground.  I don't think it -hurts-,
but my own prescription is to leave pin 3 of the rj11 not 
connected to anything.

good luck
Thanks for your prompt reply. I did try using the updater program to
communicate with my scope, however it could not find the Autostar on any
of the com ports on my computer from the advanced menu. I re-confirmed
that I was connected to com 1 and rebooted the machine just to be sure
that there weren't any interrupt conflicts, etc.

Good point about the possibility of swapped lines, I'll double check
those and let  you know how I make out. Thanks again!

And this:
um... guess who swapped the lines when he built -his- 505 cable?

the voice of experience...

Subject:	Re: 497 Troubles
Sent:	Sunday, January 6, 2002 7:45:29
From: (Jim Howard)
To: (Victor van Wulfen)

It appears that Victor may be closer than I had hoped.  Last night I was
using the default hand controller to slew slowly across the Milky Way
(of course on one of the best viewing nights I have had to date), and
the scope just stopped.  The hand controller had 2 led lights on, both
dim.  I shut it off, turned it back on, and now it is acting like my
autostar did.  It goes through its setup, with all the lights blinking
fast, appears to try to run the motors to do its syncing, but nothing
happens.  The directional buttons on it are now non-functional as well.
I am packing the scope up to take it back to where I purchased it,
hoping they will be able to swap it out for me.  I have only had it just
over a month.  If not, I guess I will be calling Meade directly.  I
still have not heard anything back on the autostar, but perhaps that is
good, as it would likely end up working for a bit then go out again, due
to what appears to be bad wiring in the scope.

How is Meade to deal with directly ?


Jim Howard wrote:
> Hello again Victor.  I read through what you had posted on Weasner's
> site.  It sounds like there is one difference between the problem that
> you had and the problem that I had.  My autostar forced the scope to
> slew in 2 directions.  That is, both alt and az motors ran
> sporadically.  I am hoping that the problem is entirely in the Autostar,
> and I do not have 2 broken wires in the base.
> I will keep everyone posted.
> Jim
> Victor van Wulfen wrote:
> >
> > Hello mr. Howard,
> >
> > I read your articles about your troubled Autostar on Weasner's
> > website. In one of the responses I described similar trouble with my
> > Autostar, you may have read it already.
> > Could you tell me what the Autostar displayed and when exactly the
> > slewing began? I myself am now stuck with a broken Autostar, a rather
> > expensive piece of junk to be honest. I have since then ordered a new
> > one that works fine.
> > If you could please keep me posted about what Meade and/or telescope
> > dealers tell you.
> >
> > Thanks!
> >
> >
> > V.A. van Wulfen

Subject:	Alignment for Dummies (was: Autostar #494)
Sent:	Saturday, January 5, 2002 11:21:29
From: (Richard Seymour)
Well, not "dummies"... i prefer "inexperienced, out in the cold"

You didn't state if you were running Alt/Az or Polar... but even so:

> I typicaly use the two star alignment method (Betelgeuse and Polaris), 

Bingo... DON'T use Polaris!!  (unless you're one-star polar aligning)

Two things combine to mess up if you use Polaris:
(a) all of the RA lines -meet- -very- near Polaris... so if you're
    off just the tinyest bit, numerically you're WAY off.
(b) they use tangents in their calculations... the tangent of 90 degrees
   (where Polaris almost is) is -infinity-.  Leads to large errors.

In newer versions of the 495/497 firmware, they -specifically- avoid
polaris (or any star above 88 degrees Dec) from usage as an alignment star.

As a rhetorical question: Why not use "Easy Align"?

If your methods aren't working as well as you think they could, why not 
-change- that one part (two-star to easy) and see if the scope can
help get past the hurdle?

have fun
who has been trying to get his lazy self to write an alignment guide,
but it's -really- hard to do so in a way that -can- be understood.
Among the biggest tips are: "don't sweat it so much", "let the 
Autostar help", "READ the Autostar's help", "visit a star party
and ask (a demo is worth (and includes) 1,000,000 words)"
Mike here: One of the points I made at the First Annual Mighty ETX Star Party last September was to "have fun". Don't sweat the small stuff and spend hours trying for that perfect Autostar alignment. "Close enough" enough works well many times!
Subject:	questions on two star align
Sent:	Friday, January 4, 2002 12:20:48
From: (Jenny Mehlenbeck)
I did say I'd be back to pick your brain.  Finally got a clear night.
First since Christmas.

RE' the etx 70 model.

Found the moon with manual controls for the first time.  Very cool!  I
can see why people complain about the focus knob.  Switching eye pieces
is a real pain.

OK, two real questions now.

1.  Initializing.  The closest city to me in the computer is 12 miles
away. Is that close enough?  I do have the correct lat and longitude for
my house. (Got that from NASAs site.)  I've read and re read the manual
but can't figure out how to in put that instead of their city choices.  
(Got real good at going through initializing process though.  Only done
it about 20 times.)

2.  This may be simple.  I let the scope get cold outside with the
batteries in it.  (Yes I do know better.  Did the stupid thing anyway.) 
When I was ready to do the two star alignment it was already moving real
sluggishly. Control panel as well as the motor.   I only know how to
locate a few stars even with a new star chart so I opted to pick which
stars to align to. Sirius was almost over head at the time.  But when I
selected it, I got a message "below horizon."  Um,   well,  NOT.   It
did however, accurately tell me the moon was below horizon and exactly
when it would rise.  (a half hour later.)  What's up with this?   Is it
just the cold batteries giving it brain freeze or is something really

Jenny Mehlenbeck   astro newbie.
Mike here: Yeah, that is close enough, as long as you can pick out the alignment stars. But you can go to the Site-->Edit menu to add/edit locations. As to the GOTO problem, I suspect the temperature/batteries could be the problem although I really wonder if the correct time was input.
Subject:	Autostar #494
Sent:	Friday, January 4, 2002 10:24:37
From: (Stratton, Scott)
I was wondering if there is such a thing is "Alignment for Dummies"?  I
seem to always be off a little on my alignment.  I typicaly use the two
star alignment method (Betelgeuse and Polaris), and I also use a bubble
level.  I seem to always have problems with tracking, and the more
objects I "go to", the further off I get.  I have trained the drives,
but I must be forgetting something.  Can you help?  I am not familiar
with all the different Acronyms; therefore, "Alignment for Dummies"
would be nice.

Best Regards,

Scott Stratton
Mike here: Well, there are some alignment tips on the Autostar Information page. You might also want to check the Tutorials page and look at the alignment tutorial there.
Subject:	Autostar Location Error
Sent:	Friday, January 4, 2002 1:53:17
From: (Jim Heal)
On a recent trip to Tasmania I asked my Autostar to select Hobart as the
operating site.  It pointed pretty well, but not as well as it has done
in places where I have entered site data manually.  When I checked the
latitude and longitude data, I discovered that the latitude was about 2
degrees different to the value in my atlas, and on my GPS.  A quick edit
and all was well again.  No doubt its just a typo on Meade's part, but
maybe users having that irritating "nearly right" pointing would find it
worth checking site data offered by Autostar against other sources of
information.  I'm using version 2.2Er, by the way.

Thanks for a great site.



Subject:	Clay Sherrod's Constellation Guides
Sent:	Wednesday, January 2, 2002 6:50:26
From: (John Collins)
Are there data files available to load into the Autostar that match in
sequence the objects in Clay Sherrod's Constellation Guide? A partial
match seems to be already loaded after using a "goto" to a constellation
and then scrolling through some of the objects. They seem to focus only
on stars in the selected constellation. I saw in one of the Software
items under the Autostar heading that I could add objects myself in a
text file (User Objects) and I guess these are the kinds of files that I
am seeking. If they don't exist, I could take on the task of creating
them myself. If  I did so, would the Autostar tolerate a different user
file for each constellation or should all of the "Sherrod objects" for
all constellations be included in one large file?


John Collins
Thornhill, ON
Mike here: See the "Autostar Guided Tours and Info" page on the Autostar Information page.
Subject:	AS 497 coordinate datum
Sent:	Tuesday, January 1, 2002 15:42:08
From: (dgriff)
Searched around your site but did not find anything specific. Was
wondering what datum (WGS 84, NAD27, NAD 83, etc) is used by Autostar
when inputting manual coordinates, and, will Autostar care if it
truncates everything past the first 2 integer minutes, e.g. 34deg 23.24'
read as 34 deg 23 min when Enter is pressed. In this case the datum is
not very important, but if the internal mantissa is kept then I would
like to be as accurate/precise as possible. Using coordinates from the
same datum will help in that respect.

Don Griffith
34  23'  9"
-117  16'  12"
NAD 83    ;-)
And from our resident Autostar expert:
From: (Richard Seymour)
The Autostar (currently) only maintains Site locations to the integer arcminute.
I believe it only uses them for figuring offset from Greenwich for time
 and precise locations for satellite passes.  
Most other things get overridden by the alignment process (if your base isn't
level, you're effectively moving yourself on its map of the planet)

I've played with setting known errors re: my location, and (up to 20 arcmin)
 i really can't detect a difference in my ETX90's performance
  that isn't corrected by alignment.

During operations, the Autostar converts the Lat/Long via single precision
math to radians, and then to Sine/Cos values.  
But retention of Site Coordinates across power-cycles are as
truncated integer arcminutes.

have fun (precisely)

P.S. You  might be able to determine the datum by reviewing its
stored list of Lat/Longs for the various cities... if we
knew -where- they're choosing the "spots"
(the Autostar's Greenwich, for example, is -not- Long=00 00 00)

I wonder which datum they'll ask their LX200gps to refer to?

Another cross-check would be to enter your site,
then use the hold-MODE status display of Local Sidereal Time
to get a tighter fix on what longitude it thought was 
immediately overhead.

Creative use of the Alt/Az status readout could also be cranked
into testing for its idea of self-location.

A reverse question: which datum (WGS 84, NAD27, NAD 83, etc)
 is the -sky- using?
i.e. if you convert from RA to Longitude,
and Dec to Latitude, which datum do you end up on/with??

Feedback Archives

Check the Feedback Archives for previous editions of the Autostar Feedback page.

Return to the top of this page.

Go to the ETX Home Page.

Copyright ©2002 Michael L. Weasner /
Submittals Copyright © 2002 by the Submitter