Last updated: 28 March 2005

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This page is for user comments and information of a general nature or items applicable to all LXD55 models. If you have any comments, suggestions, questions or answers to questions posed here, e-mail them to me and I'll post them. Please use an appropriate Subject Line on your message. Thanks.

Subject:	I need some help. Autostar Error.
Sent:	Sunday, March 20, 2005 12:03:22
From:	Luis G Castillo (gercasst@yahoo.com)
I have not found information in the web for my problem. I know that you
are an expert in LXD 55 mounts and maybe you can help me.

I have a LXD75 SC8 with :

The mount leveled with torpedo and bubble levels.

The Polar scope aligned with the mount.

The finder aligned with the optical tube.

The optical tube aligned with the mount.

The counterweights and optical tube balanced.

The drives trained the motors calibrated.

Polaris located between the 40-60 marks of their illuminated reticle.

I have used One, Two and Three Stars alignment methods.

But :

1. The Autostar have very bad GoTo pointing. When I request objects to
Autostar (too with the High Precision method),  the optical tube is
positioned in all the cases to the west with a difference of  5- 10 (15
- 20 arc minutes) in Right Ascension (RA) from the real position of the

2. When I try center one object from the eyepiece border with the RA (<)
Autostar key,  the object back to their position in the eyepiece border.
I need to make several attempts for center the object in the eyepiece.

3. When I try to align with Capella and Regulus/Spica and center
Regulus/Spica, the Autostar display the message : Alignment Failed.
Check the stars.

And with this problems I cant use correctly the Autostar for pointing to
deep sky objects.

I updated to 33Ef software version. The problems are the same. Next, I
back to 32Ei version and problems remain.

I will appreciate your help.

I live in Mexico and its difficult for me call to Meade.


Luis G Castillo

Mike here: Couple of thoughts: When you updated, did you reTRAIN DRIVES drives? You should; that should cure the "rubberbanding". As to the pointing error, that almost sounds like a time problem. Have you set the proper Daylight Saving setting? If you are picking the alignment stars, be certain they are at least 90 degrees apart.


Thanks for your response.
Yes. I did reTrain Drives after each update and the site, time, and
date, time, site values and Daylight Saving setting are correct.

Tonight I will advance to one hour the Autostar time and will observe
the results.

Luis G Castillo
First, I delayed  the Autostar time 30 minutes and I aligned the scope
with Betelgeuse and Alioth (UMa). The pointing error in two stars
requested to Autostar was diminished to 1  and 5 respectively.  

Next, I delayed 1 hour the Autostar time, but the alignment failed.
Message : "Alignment Failed. Check the stars". Tomorrow I will try


Luis G Castillo

Subject:	re: RA Motor
Sent:	Monday, March 7, 2005 21:56:52
From:	Richard Seymour (rseymour@wolfenet.com)
The 4th step in the reset/cal/train  sequence is to adjust
the RA Percentage.  
Recent firmwares pre-set this (far) too high (50%) and that can
cause exactly the symptom you're describing.

Try lowering the values (and the Dec Percentage, too).

good luck
Mike here: I haven't seen that with 3.3Ef but should know more this weekend.


They switched to 50% back around 3.0 ... 
Clay posted an unhappy note about it back then 

It's still true in v33Ef (reset sets 'em to 50%)

have fun
Mike here: But my scopes are working fine....


it only changes them if you Reset.
If you simply update, the old numbers survive.

have fun
From:	Offwork11@aol.com (Offwork11@aol.com)
Thanks for all the information. I decided to call Meade. I purchased a
new RA motor. I have already tried those suggestions. To no avail, the
problem remains. I need to fix this anyway. I will probably get one of
the new LX90LNT's and try to sell this one. Meade said it will produce
shaper images than the 10 inch LXD 55, and with the UHTC coating it will
be like having a 9 inch mirror. I like the LXD 55, but it is quite a
chore lugging it around. I also purchased a GPS mate from
astro-engineering. It works great and no other software or keys for
other controllers are needed. I costs a little more than the Star GPS.
Less complicated to use. I even changed my site to Cairo Egypt and it
hit all the alignment stars on the money every time in Virginia beach
VA. So thanks for both your time and interest. Will let you know what
happens when the RA motor gets to me. If the problem remains after that,
I surmise it must be a problem with the autostar itself.
Shep Kaplan

Subject:	re: Teething troubles with LXD75 SN10
Sent:	Monday, March 7, 2005 21:53:35
From:	Richard Seymour (rseymour@wolfenet.com)
The gradual degradation of GoTo accuracy on an LXD55/75 can frequently
be caused by one of the transfer gears (the gear pair just before the 
worm) slipping on its shaft.  I think there is a set screw you can
tighten, if you open the access panels.
Don't -over- tighten it.

good luck

Subject:	Autostar Suite - Connection to the telescope error "Invalid ACK response from LX200"
Sent:	Monday, March 7, 2005 02:48:29
From:	Hyde, Andrew
As I do not have a serial port on my PC I am attempting to use my modem
in Com Port 3 mode - However as this is proving unsuccessful I hoped you
might be able to help.  I receive the following error Message when I
attempt to use the  "Autostar with Com Port" option to connect my PC to
my scope.  The error states "Invalid ACK response from LX200".  Please
can you advise what I need to do.

I have the following equipment:
- LXD55 8 Inch Schmidt-Cassegrain with Autostar
- Sony Vaio laptop with internal CXT modem (Com Port 3) - Windows XP
Home Edition (Centrino 1.7ghz - 512mb RAM)
- Autostar suite supplied with a Meade DSI. (Feb 2005)
- I am connecting plugging the Autostar cable into the modem cable port
(it fits correctly)

When I purchased the DSI I uninstalled the internet based Meade software
which I had previously down loaded. I have not downloaded any new
software onto the Autostar (I was hoping to do this once I had the
Autostar connection working)

I have set the PC's internal modem to a 9600 baud rate (as per the
Autostar) and selected the following options on the Autostar Suites
Communications set up
Comm Port = 3
Baud Rate = 9600
Flowcontrol = None
Stop bits = 1
Data Bits = 8
Parity = None

If I attempt to use any of the other comms options on the Telescope
control I get a "Read timeout Error!"

You help would be greatly appreciated

Mike here: Simple answer: you can not use the modem port; the connection must be RS-232. You will need to purchase a USB-serial adapter. See the Helpful Information: Autostar Info page for lots more info.
Subject:	Teething troubles with LXD75 SN10
Sent:	Wednesday, March 2, 2005 20:05:30
From:	Colin (drvibe@hottownmusic.co.uk)
I haven't long bought this scope (2 weeks) in the UK, and I'm pleased
with the OTA the mount has given me problems. First after calibrating
and training, good polar alignment and three star alignment, the goto
pointing is at first fairly good but degrades after a few slews and then
it's pot luck whether the target is in the 26mm eyepiece or not. Second
it tracks too slow in sidereal or as I have observed without anything on
the mount the RA cogs stick regularly when tracking.

Now I read in one of your replies that a 12v 2500 mA supply is required
for this mount and so far this all I can think of that is wrong with my
set up. I have a 12v rechargable battery rated at 1900 mA. Could this be
the common problem? Or should I get heavy with my suppliers and replace
the mount!

BTW - excellent site, I may do the same for people with Digital Audio
problems, which is my bag!
Mike here: Power could be the problem but it likely wouldn't show up in tracking. I would recheck the mount selection in the Autostar. If OK, do a RESET, CALIBRATE MOTORS, and then TRAIN DRIVES (don't forget to train in both axes). Make the training as accurate as you can using a distant fixed object. If the problems still appear, do an update to the current Autostar version 3.3Ef available on Meade's site. You will need a RS-232 port and a #505 cable (purchased or made). Meade has a Windows app updater and a Mac version is also available (see the Helpful Information: Autostar Info page).


Thanks Mike, I have the correct mount, and have repeatedly and
religiously Reset, calibrated and trained as accurate as humanly
possible, however I have Ver. 32E so I'll update that and get a heavy
duty PSU. Then if all else fails, it's time to call upon my subtle blend
of psychology and extreme violence to get the mount replaced!
Mike here: Updating the Autostar could cure it.
Subject:	RA Motor
Sent:	Tuesday, March 1, 2005 14:08:36
From:	Offwork11@aol.com (Offwork11@aol.com)
I have a lxd55 10 inch sn. I've had it for about three years and it has
performed fine for most of this time. My problem is that recently the RA
motor will roll the scope in the opposite direction after slewing it
with the autostar. In the other direction the motor works fine I called
meade, they told me to retrain the motors. So I did. It appeared to fix
the problem. However after doing an "ALIGN" function (easy, one star,
two star) the problem reappears. I reset, calibrated and retrained
again. I took the GEM totally apart and inspected it. It appears to have
no defects. The problem still exists. Could it be the autostar it self.
Do you know of any other recourse that I can approach? Thanks for your
Shep in Virginia Beach.
Mike here: The RESET, CALIBRATE MOTORS, and TRAIN DRIVES (you did TRAIN in both axes?) should have cured any Autostar related problem. If not, you could update the Autostar to the current version (3.3Ef); you will need a RS-232 serial connection and the #505 cable (which you can make). Meade supplies Windows software and Mac OS X is also available (see the Helpful Information: Autostar Info page on my Sites).


I just updated the autostar like you suggested and I all ready have the
whole 505 set up. Then I did a reset, calibrated motors and trained
"both" motors. The problem still exists. Do you think it may be the
autostar itself. Also it does not do it when the targets are in
terrestrial mode, only in astronomical.

thanks for your time
Mike here: Maybe I misunderstood your comment that "the scope in the opposite direction after slewing it with the autostar". That sounded like "rubberbanding" but maybe you meant something else?


Let me try again. The RA motor gears will  (wether the scope is mounted
or not) and if the scope is not mounted I do not have the weights on.
Move in the opposite direction very noticeably moving any object in the
center of the eye piece, almost out of the field of view, then it stops.
This only happens in one direction. This has never happened before. It
does not occur in the other direction. I even went as far as changing
the direction of the arrows with the autostar function. I hope this
explains it.
Mike here: OK, that still sounds like "rubberbanding". How you are doing the TRAIN DRIVES?


I train the drives in accordance with the autostar commands.
Mike here: What I meant was "what eyepiece was used, what object, what slewing speed, which axis was done first?"

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