Last updated: 31 July 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:	Re: LXD55 Autostar(497) update problem only to 26E
Sent:	Thursday, July 28, 2005 20:00:55
From:	DANIEL P KIES (levitan50@msn.com)
Mike, It does exactly the same thing. Daniel
Mike here: Rats. Try reversing the Autostar cable to the LXD.


Mike, I'm not even going to ask why, but I will say that "You are the
MAN" Works like a champ.

Thank you, Thank you, and Thank you. Yes I did get my Meade Lxd55 10" SN
from OPT :)

Daniel Kies

Subject:	LXD55 Autostar(497) update problem only to 26E 
Sent:	Wednesday, July 27, 2005 20:47:46
From:	DANIEL P KIES (levitan50@msn.com)
I can only update my Autostar to version 26E. Anything above that causes
my RA motor to start running as soon as I enter the time and date. Any
suggestions ? Thanks, Daniel Kies
Mike here: Have you done a RESET, CALIBRATE MOTORS, and TRAIN DRIVES following the update?


I can't get to the reset function as the RA motor runs right after I
enter the time and date and run until Autorstar gives me a motor fault.
Mike here: OK. Lets try a SAFE LOAD and reload a fresh copy of the ROM. Hold down the ENTER and SCROLLDOWN keys and then power on the LXD. Run the Autostar Update application which will detect the SAFE LOAD mode; update to 3.4Ec.


I will try that tonight. I'll let you know. Thanks for all your help and
quick response. Daniel

Subject:	Polar Alignment Viewfinder, No second Star?
Sent:	Wednesday, July 27, 2005 13:32:11
From:	Davin C. Enigl (enigl@earthlink.net)
I just got my LXD75 SN10AT.  I went to use the PA viewfinder telescope. 
To my surprise, the reticle has no second star to rotate the RA to, to
get a two point line-orientation.  Polaris is there, fine, but all the
PA scopes I've used also have SAO 209 (the 6.5 magnitude star next to
Polaris).  The reticle has the standard four Southern "Octantis" stars
when you really only need two stars.  What do the Northerners do?

Ref. Instruction Manual LXD75 page 52, Appendix B.  What they say there,
will not work for Northerners.


[P.S.: I also had to make my own #505 cable because Meade's cable are
wired, the replacement was wrong too and so was their website's pin-out
diagram.  Thanks to your site, weasner.com, I got the correct pin-outs. 
But geewizzzz, what gives with Meade?]

-- Davin C. Enigl, MEAS.

Search for Life in Space

Mike here: See the article "Using the Polar Alignment Scope" in the LXD55 / LXD75 Information section on my LXD55 Site.
Also, please read the Email Etiquette item on the LXD55 Site re: Spam Blockers. Thanks for understanding.
Subject:	re: Is my LXD-75 broken?
Sent:	Monday, July 25, 2005 19:36:22
From:	Richard Seymour (rseymour@wolfenet.com)
Two things i can think of to check:
(a) check the Setup > Telescope > Dec Ratio  matches the value in the RA Ratio
 (the sign may be changed, but the number should match).

(b) open the DEC inspection panel again, and look at the encoder disk
 (the slotted wheel which is at one end of the motor).

It may be dirty (thrown grease), it may be spinning loosely on its shaft.
It may be horribly -bent-.  All of these have been seen by others.

The fact that the scope travels further than the Autostar is commanding
indicates that the encoder is seeing too few light interruptions.
Any of the above three conditions can cause that.

Some folks attempt a repair (if it's dirty, be -very gentle- about
cleaning it (it's fragile, see "bent", above).  If it's spinning 
freely, some folks have glued it to the shaft.

Or exchange it with Meade.

good luck
From:	Dave Wallace (d_wallace@ecrm.com)
Richard Seymour on Monday, July 25, 2005 at 10:36 PM
-0500 wrote:
>Two things i can think of to check:
>(a) check the Setup > Telescope > Dec Ratio  matches the value in the RA Ratio
> (the sign may be changed, but the number should match).

I checked that.  The magnitudes of the ratios are identical (about 2.5).
>(b) open the DEC inspection panel again, and look at the encoder disk
> (the slotted wheel which is at one end of the motor).

Actually, the inspection port is on the opposite end of the motor
assembly. You can't see the encoder from there.  So I had to remove the
bottom cover from the motor assembly to inspect the encoder.
>It may be dirty (thrown grease), it may be spinning loosely on its shaft.
>It may be horribly -bent-.  All of these have been seen by others.

I saw nothing obvious.  The encoder appears to be tight on the shaft,
clean and not bent.  (It looks like the encoder attaches to the shaft
with a 1/2mm (maybe 1/32") Allen screw.  I don't have the necessary
wrench to turn that screw.)
>The fact that the scope travels further than the Autostar is commanding
>indicates that the encoder is seeing too few light interruptions.
>Any of the above three conditions can cause that.

That was my diagnosis as well.  Since there doesn't seem to be an
obvious problem, I guess the mount has to go back to Meade.
Another thing to look for is the sensor/LED combination being
slightly askew so they're not cleanly seeing the slots in the disk.
I don't know if the LXD's are up on wire leads or not. 

But "trip to Meade" (or dealer exchange) looms likely...

good luck

Subject:	Is my LXD-75 broken?
Sent:	Thursday, July 21, 2005 06:02:30
From:	Dave Wallace (d_wallace@ecrm.com)
Ever since I bought it (November, 2004), I've had trouble understanding
how the LXD-75 is supposed to operate and why it never seems to point to
the proper part of the sky when I do a GOTO.  Well, this week I spent
several evenings with the scope set up in my living room doing a
systematic analysis and I've come to the conclusion that maybe the
problem is in the scope and not in my ability to understand how a GEM
mount works.  (My other scope is a fork mounted ETX-90 OTA, also
controlled by an Autostar 497.)

Here's the background:

1.	The Autostar has been updated to version 34Ec firmware.

2.	I've done a RESET, Calibrate (with the power supply I used
throughout these tests) and Train Drives.

3.	My latitude (roughly 42.5 degrees north) and longitude (roughly
71.5 degrees west) have been entered and verified and also compared to
what the Autostar has for the location of the nearest town (Lowell, MA).

4.	My time zone (-5, Daylight=yes) has been entered.

5.	I haven't messed with the percentages or ratio settings, turned on
high precision, changed slew direction settings, turned on quiet slew or
attempted to to a PEC calibration -- all these settings are still the
factory defaults.

6.	I'm using the mount's setting circles to determine if the movement
of the mount and the Autostar's RA and DEC display agree.

Here's the observations:

1.	When I attempt to do an Easy Align, the mount slews to the first
target star -- Arcturus (which should be roughly at culmination and
about 45 degrees above the southern horizon) -- and winds up pointing at
the floor.  Yes, pointing (in)accuracy is THAT bad!

2.	After returning the mount to polar home position, I manually slew
in right ascension by six hours.  According to the RA setting circle,
that's how far the mount moved (90 degrees).  Slewing in the opposite
direction by six hours returns the mount to its original position, to
within my ability to read the setting circle.

3.	I manually slew the mount by 45 degrees in DEC, as indicated on
the Autostar.  But according to the setting circle (and my eyeballs) the
mount has moved over 180 degrees!  I attempt to return the mount to its
original position by slewing in the opposite direction.  The mount stops
about 20 degrees short of the proper DEC.  (Yes, the DEC lock is firm,
not over-tightened and the mount is balanced.)

My conclusion:

The DEC drive encoder isn't sending the proper number of pulses per
rotation or there's something seriously wrong with the electronics
package for the DEC drive. (And the RA drive is apparently okay.)

Other tests I could try, if you think it's worth looking further (in
order of inconvenience):

1.	All slew tests were done at maximum rate ("9" on the keypad).  I
could try slewing at a slower rate.

2.	I haven't opened up the DEC motor assembly (the scope is still
under warrantee).  I could do a visual inspection of the encoder.

3.	I have another Autostar.  I could swap it in (though it's
currently a couple of versions back from the current one and is
configured for my home-built mount).

Or should I simply contact Meade Customer Service?
Mike here: I think the clue is "I manually slew the mount by 45 degrees in DEC, as indicated on the Autostar. But according to the setting circle (and my eyeballs) the mount has moved over 180 degrees!". That indicates either the gears are slipping or the Autostar is miscounting. Checking the gears for slippage, especially the DEC gear is easy (at least on the LXD55 I have). Start there. If that isn't it, then since you have another Autostar, it would be good to test that just to rule in or out the Autostar as the culprit. If that doesn't solve it, then I would suggest contacting Meade; they will probably have you return the mount.


Okay, I popped the access cover and inspected the gears; they mesh
properly. Swapping in the other Autostar did not change the behavior
either: RA still moves at the proper rate and DEC still doesn't.  Looks
like I need to talk to Meade.

Thanks for your assistance.  If Meade has anything significant worth
reporting, I'll let you know.

Subject:	Re: lxd55 8sn RA gears
Sent:	Wednesday, July 20, 2005 00:02:49
From:	Terry King (terry.king46@ntlworld.com)
Thank you Mike,exactly what I need,many thanks.
Regards Terry

Subject:	lxd55 8sn RA gears
Sent:	Monday, July 18, 2005 08:20:29
From:	Terry King (terry.king46@ntlworld.com)
Thanks for great site.

Can you tell me how to get at the gear wheels in the RA housing, the two
visible wheels,one brass,the other steel I think, have become offset, so
they no longer mesh!

The mount is the German type as supplied with the LXD55 8"SN a couple of
years ago.By removing the little inspection cover,the two wheels in
question are immediately visible.

Thanks for reading.
Best regards
Mike here: See the article "Fixing a Slipped RA Gear" in the LXD55/LXD75 Information section.
Subject:	Mirror refinishing & more
Sent:	Thursday, July 14, 2005 22:02:49
From:	J. Winterroth (jwinterroth@socal.rr.com)
1) One site on the web was claiming that with Schmidt (and other designs
using mirrors) that the mirror's need to be recoated every 5-7 years
(which sounds expensive). Is there any truth to that? - or is that one
of those things that was true 50 years ago?

2) I've also seen postings that a reflector isn't as efficient as a
refractor - some claim that a 8" reflector design only gathers as much
light as a 4" refractor - due to things like the spider and central
obstruction. Looking at the specs on the Meade site they give a loss for
the central obstruction (about 15%) but not the spiders. In your opinion
is the light gathering really impeded that much more by the spiders?
 jim winterroth
Mike here: Depending upon the care that the telescope gets and the conditions it is used in, mirror coatings (and other coatings) may or may not last decades. But it is not unusual for professional telescopes to be recoated every few years. Even the 200" Hale Telescope at Mt Palomar gets recoated. (Now that is expensive!) But my ETX-90 (from 1996) is still fine. My Edmund 3" Newtonian (from 1961) does need to be recoated though. As to obstructions, yes the reduce somewhat the light reaching the eye (or imager) but usually the cost difference more than makes up for the loss. For example, take a quality 8" Schmidt-Cassegrain and price that for a quality 8" refractor. Which can you easily avoid?
Subject:	supernova?
Sent:	Thursday, July 14, 2005 16:23:07
From:	vze3trgg@verizon.net
I have been a visual amateur astronomer for many years but have only
very recently started imaging.  I have a Meade 5 inch achromatic
refractor on an LXD55 mount. I took my first picture of a galaxy using
my Canon Rebel camera at prime focus on July 2, 2005. I chose M51 to
image as it was my first attempt and the galaxy is pretty bright. I took
nine 20 sec images and stacked them. I have attached the resulting
image. I have since leared that a supernova was discovered in M51 at the
end of June 2005.  It was supposedly at magnitude 13.5. I was wondering
if the supernova is visible in the image that I took. Would any of your
forum participants know and be able to tell me?

Rick Evans

Mike here: It looks like it might be just visible. Check the photo on the LXD55 Guest Gallery: Deep Sky from Dieter Wolf posted on 11 July.


Thanks for the reference to Dieter Wolf's photo, it appears that I
really did catch the supernova on my first astrophoto run at a galaxy. 
I thought you only had the ETX site and was amazed to find the LXD one
as well;;; great work and an invaluable reference site!

A couple of questions if you have the time...  I'm learning to respect 5
inch achromatic refractors for deep sky photography as they are cheap,
interchangeable on GEM mounts, there is little vignetting and the focal
lengths are managable. I just  ordered an F5 instrument  to complement
my F9.  I've upgraded my LXD55 to an LXD75 hoping that the tracking will
be better (i.e. longer before the guidestar is lost). I've opted for the
Canon EOS 20a as my primary imager (fast, color, many pixels, noise
reduction circuits, hydrogen alpha filters). My Meade LPI autoguider (on
a Celestron 80mm F5 guidescope) can't seem to show or find stars fainter
than 6th magnitude which is troublesome (there aren't that many of
them).  Do I just need more experience with the Meade or should I opt
for another autoguider? ( I get beautiful 3 minute exposures of Vega
(pinpoint) with the 5 inch F9 on the LXD55 mount so I must be doing
something right.)  Any advice would be much appreciated...

Rick Evans
Mike here: While the LPI/LXD combination can do some autoguiding it is certainly not as precise as a higher-end imager/autoguider on a higher-end mount. But keep in mind that image stacking is a way to overcome this limitation. You just use lots of short exposures.


Yes, but there is a lot of noise with the short exposures and it is a
bear to image process it away!  Is there any hope that the system I
describe will be capable of say 3 minute autoguided exposures that I can
stack (better by far than 20-30 sec where I am now) or should I break
down and get a losmandy mount and an STV? My local camera shop advises
an LX200 but that is not my style at all!

PS = Plan to become a paid up member of your site today or tomorrow at

Thanks again for your patience,

Mike here: The use of a "dark frame" can subtract out that noise in software. Depending upon how accurate your alignment and the image scale you may (or may not) be able to get away with a 3 minute guided (not autoguided) exposure. But experience can help with the LPI and autoguiding. Stick to using bright guidestars until you get more experience. Alternatively, you can always manually correct for tracking errors since you have a guidescope mounted.
Subject:	re: Rikaline GPS adapter
Sent:	Monday, July 11, 2005 22:30:03
From:	Richard Seymour (rseymour@wolfenet.com)
To make the Autostar recognize and interpret a GPS unit's output
requires a major reprogramming.  That's part of the package Scopetronix

You can buy just the programming directly from its author at:

have fun
From:	David (radioactive@frontiernet.net)
Thanks for the info, Dick.  I do have the 6010 unit discussed in the web
piece.  I was a little confused about brands, but obviously I have the
right one.  It will be fun to get the software loaded and check it out!
Thanks again

Subject:	re:  Autostar 497-LXD55/75 Motors
Sent:	Monday, July 11, 2005 22:28:08
From:	Richard Seymour (rseymour@wolfenet.com)
Visit and join the Yahoo Roboscope group, whose primary mission is
adapting Autostars and the various Meade motor units (including the LXD)
to non-Meade mounts...


have fun

Subject:	Re:Rikaline GPS adapter
Sent:	Monday, July 11, 2005 16:50:17
From:	David (radioactive@frontiernet.net)
I just bought a Rikaline (advertisement was "Scope-Tronics, but I got
this one instead) GPS adapter for my LXD75 SN10 AT.  The instruction
sheet for the unit pointed to your Website for details on finishing the
installation.  Are you or your company affiliated with that product?
Mike here: No, not affliated with the company but there is some info on the Helpful Information: Autostar Info page on GPS add-ons.
Subject:	Autostar 497-LXD55/75 Motors
Sent:	Saturday, July 9, 2005 08:47:33
From:	Luis De Vivero (ldevivero@socal.rr.com)
I want to add GoTo to my Vixen Super Polaris. I am considering the
Autostar 497-LXD55/75 Motors. Are LXD55 motors adaptable to a Vixen
Super Polaris Mount? I want to know how much altering, if any would be
Thanks, Luis
Mike here: Possibly. See the article "Steve Bedair's "Go To" Mounts" on the Helpful Information: Autostar Info page. But I suspect you would have to do some major mods once you got your hands on the proper motors. There are likely many LXD55 tripods available now available since Meade offers the LXD75 tripods separately. That might be a cheaper way and better way to go.


Thanks for the tip.

Subject:	Equatorial Mount in AZ-EL mode?
Sent:	Friday, July 8, 2005 18:08:20
From:	David (radioactive@frontiernet.net)
fabulous site!  I'm not getting anything else done due to all the good

I can't find anyone who really addresses this question directly.  Using
a LXD75 refractor as an example, is it possible to set-up the Equatorial
mount in such a way to give Alt-Az coverage?  It appears by looking at
it that if the "latitude" adjustment is brought down all the way, the
scope would be pointing off to the side, but the RA and DEC swings would
be Alt-Az at that point - is that true, or doesn't it work that way in

Also - it would seem that the fork mounted "goto" scopes could track
properly for astrophotography (long times) - why would a wedge be needed
to put it in equatorial mode for that purpose - is it just physically
impossible for the computr to steer it right, or is the computer
basically not good enough?

Mike here: There are two separate questions there. The first would work but a GEM will have a problem with the counterweight shaft striking the tripod unless you mount GEM head on a pier instead. As to astrophotography in Alt/Az, that results in what is called "field rotation" during the exposure. You can add a "field derotator" but that adds cost and weight.


Thanks much for the response on the Eq mount.
One other question - do you know if they changed the way the telescope
attaches to the mount between the LXD55 and LXD75 series?  Specifically,
would an LDX55-AR6 attach to the LXD75 mount directly?
Mike here: It has been awhile since I saw a LXD75 mount but I believe the same mounting bracket should work.

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