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LX90, LXD55, & ETX Specific Issues

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Subject: International Meade LX90 Telescope Users Group & Website

From: Wayne Powell <> Date: May 2001

Would you consider linking to our current web resource for the LX90 on the home page: International Meade LX90 Telescope Users Group or IMLTUG Archive & Mailing List:

  <>    Note: should open a new window over this one.

We have over 450 members and are in the process of establishing an online web site resource <>. This group is the first and largest international online user group of prospective and current Meade LX90 owners and enthusiasts.


Subject: LX90 vs. LX200   Top

From: Janet Miller <LX90 Website>

In comparing the LX90 vs. the LX200, the optics should be the same. The LX90 doesn't have PEC (periodic error correction for the RA drive), but it will accept an autoguider. The forks are little less substantial (probably a little better than the LX50s are). I have no problems mounting a Nikon F at prime focus in regards to stability. The LX90 comes with the standard field tripod, but no wedge. I've heard that Meade has finally come out with an adapter to mate the LX90 to the LX200 standard wedge though. I had an adapter made for mine prior to them catching up to the demand.

The Autostar has been excellent for me, the latest update has some changes for the Accesory Port Module that the LX90 uses for guiding, reticle and electric focuser. Finally, the GoTo accuracy is not rated to be as precise as the LX200.


Subject: Differences in LX200 vs. LX90 OTA --part 1 of 2  Top

From: Janet Miller

The back of the OTA is different from the LX200. It's curved (somewhat sperical) with a small, flat cutout area for the focuser. There's also 2 vertical screws just below the rear port for the Accessory Port Module to attach. The corrector end seems to be the same. Mounting screws are the same as the 8" Lx200, as I have the Meade weight set and Losmandy dovetail mounted on my LX90.

There's a pretty good image of the back of the OTA here on one of my web pages:
  <> Note: should open a new browser window over this one.

The screws for the APM and the spherical back are pretty obvious in the picture at the bottom of the page.


Subject: Differences in LX200 vs. LX90 OTA --part 2 of 2   Top

From: Wayne Powell <>
           IMLTUG LX90 User Group Moderator

Meade has been pretty specific with our group that the LX90 IS ABSOLUTELY NOT the same as the 8" LX200 OTA, though the "optical system" is the same and theoretically they should perform the same.

The LX200 OTA has a significantly different "back end", compare pictures of the LX200 & LX90 Rear Port & Focuser assembly, you'll soon spot the difference and be able to see if you received a mixed up corrector plate ring.

We've been charting significant numbers of QC problems from Meade as of late, perhaps nothing new, but seeing as their stock is in the dumpster, I'm surprised (based on the number of formal complaints) that they haven't made a positive statement to address the issue.


Subject: LX90-- Pitfalls to Avoid    Top

From: Tom Heisey <> Date: 2001

I'm a fairly experienced amateur astronomer and a computer manager. One of my key reasons for purchasing the LX90 was for public outreach programs, including satellite discussions. Naturally, tracking the ISS with the scope & video camera would be a great crowd pleaser.

As a new computerized scope user, I fell into several pitfalls. I'd like to warn other newcomers about these problems:

1) #505 Kit:
I ordered the LX90 with the #505 cable set with the software, assuming that the software would be required to update the AutoStar computer. WRONG. The disk contains a bundle version of Starry Nights and Astronomer's Control Panel (to control the scope), but makes no mention of the updater program. Unless you want Starry Nights, save the $20 and by the cable kit only. (Better yet, look at the 505 manual and build your own!)

The actual updater program can be found at:

and the 505 cable manual can be found at:

Mike Weasner has a quick diagram for making your own cable at:
    <> and

2) Updater layout:
The updater program is poorly written, poorly documented, and a bit confusing to use. After getting accustomed to the strange layout, it works OK, but could use some refining. Drag-and-drop updating is frustrating and it took me a long time to realize that you had to drag-and-drop the file onto the button! (What happened to Windows programming standards?)

3) Upgrade problems:
One strong warning - Pause before your attempt to upgrade the AutoStar OS! I clicked the "Get update" and the system supposedly downloaded the latest update, so I clicked the upload button. After 20 or 30 minutes of uploading, the AutoStar showed I had actually stepped backwards from 22e to 21e! After a tech support call, I did a manual download and upload of the 22eh ROM, so all is well.

4) Updates erase drive training:
Updating the ROM seems to destroy the drive training, which left me rather disappointed and confused after my first update. I wasn't sure what had happened and it took a while to find the remedy. However, a quick retraining session and the scope was back to working great.


LXD55 Specific Issues


Subject: LXD55 SC-8 UHTC Sites --part 1 of 2

From: Mike Weasner <> Date: Jan 2003

Andres Valencia wrote:
> If there are other MAPUG participants who would like to exchange information
> on the LXD55 mount or the SC-8 UHTC OTA, I'll be monitoring this list and
> will try to contribute my grain of sand.

I have started a LXD55 site to document my LXD55 8" SC experiences and provide a source of feedback, tips and links. This is a companion site to my Mighty ETX Site, which has been online for six+ years. Have a visit:
    <> Note: should open a new browser window over this one.

I intend to support the LXD55 Telescopes Yahoo Group. I have been monitoring the group since I made the decision to acquire the LXD55 8"SC. I recommend that LXD55 users sign up for the Yahoo Group.


Subject: LXD55 SC-8 UHTC Sites --part2 of 2  Top

From: Richard Harris <> The LXD55 Portal:

   <> site is rich with information on the LXD55 scopes, with an on-line store for LXD55 related items including a video for first-time set-up.


Subject: LXD650 Mount Good for Imaging? --part 1 of 2  Top

From: Blair MacDonald <> Date: Dec 2003

----- Original Message -----
From: Mark de Regt
I am an experienced imager with the LX200. I have purchased a small APO refractor which I will piggyback on the LX200 for wide field imaging. I am interested in also getting a relatively portable mount so I can take the little Tak to clearer skies and image. The LXD650 mount is priced reasonably, especially used, and I was wondering if anyone has experience imaging with one. I will be imaging at very low resolution/image scale, obviously, so I don't need the most perfect mount, but I was wondering, basically, if this mount is comparable to the LX200 mount in accuracy, steadiness and reliability.

----- End of Original Message -----

Mark: I use a LXD650 with an 8" Schmidt Newtonian mounted on it. The mount tracks well and works fine for astrophotography, both CCD and film. With a 416XT, a Vixen 60mm guide scope and a 201 autoguider the mount is near capacity but works fine. Balance is critical, if it is not perfect the mount will stall as the motor drivers overheat (this always seems to happen 19 minutes into a 20 minute exposure). If you want to see some images let me know and I'll send you some.


Subject: LXD650 Mount Good for Imaging? --part 2 of 2

From: Ron Burch <>

HI, Mark, I have had an LXD 650 for about five years. I have found it to be much more stable than the LX 200 mounts - it does not "vibrate" in low breezes the way that fork mounts tend to do. I have been extremely pleased with the performance and reliability. I bought it used; it had just been refurbished at the factory. It sits in the garage through extreme heat in the summer and extreme cold in the winter, and starts up perfectly every time I use it. (I have used an 8" SCT on it - this is near its load limit although the ammeter does not register pain, and most often use a Televue 85 mounted on a saddle with a guide scope). Even with large, heavy image trains attached, tracking is very dependable - this includes the 8" SCT but it has to be balanced very carefully. This mount is quite portable since the head is carried separate from the tripod -- I would guess that each weighs somewhere around 35-40 lbs not counting counterweights.


ETX Topics


Subject: ETX Info Site URL      Top

From: Mike Weasner <>

Contains large assortment of subjects and suggestions for using and improving your ETX.

Note: should open a new browser window over this one.


Subject: ETX/EC Repair & Tune-Up Page   Top

From: Jordan Blessing <> Date: May, 1999

I have put up a page dealing with common problems and solutions with the new ETX/EC. It contains repair and tune-up tips along with about a meg of images showing the internals and repair procedures. I think many could well use it (unfortunately) if you could find a place for it amongst the other "Meade Advanced Products".

ETX/EC Tune-UP Page: <>
Note: should open a new browser window over this one.


Subject: ETX Repair Service   Top

From: Tim Crawford <> Date: Jan 2003

I just received my ETX back from Arkansas Sky Observatory. Author and Professional Astronomer, Dr. Clay Sherrod does a fantastic job of Super Charging, repairing and tune-up. My ETX scope had many problems with a lot of them being quite major.

His inspections and repairs are extensive and through plus you get upgrades to your Autostar.

I would urge you to contact him with your specific problem as your first option. A Description of the 102-point inspection procedure is listed at <>. Dr. Sherrod can be reached at <>. I think you will also be surprised by his very reasonable pricing.

FYI, for those of your unaware, Dr. Sherrod also provides his services for the LX line as well as all major brands of refractors, SCT's and Newtonian telescopes. I also just received back my LX200 12" classic from Dr. Sherrod. With both of these scopes I was very impressed with the very detailed commentary of what was repaired and adjusted as well as a report on the optical performance and the drive system, after adjustments and repairs. Each Scope also had a Certification label attached attesting to the Supercharge Service.


Subject: ETX Collimation Technique   Top

From: M. Newton <>

I succeeded in collimating my ETX. First, I took the focus knob off, 3 screws off the plastic rear cell, and I unscrewed the OTA from the plastic rear cell. You'll find 3 sets of push pull screws on the back of the OTA. They tricky part is getting an eyepiece on the back of the bare OTA. I used a VERY SMALL amount of super glue to TACK a Scopetronix SCT adapter (the one especially made for the threads on the back of the ETX) onto the rear cell. I threaded a SCT visual back onto it and then inserted an eyepiece. The scope went from nice views to SPECTACULAR views after correct collimation.

I know this may sound confusing, but it can be done.


Subject: ETX70AT Computer Control Questions   Top

From: Dick Seymour <> Date: Jan 2004

> Could someone please advise me on whether it is possible to connect
> an ETX70AT up to a computer and use a planetarium program to control it?
> The scope has the AutoStar controller without the numeric keypad.

That's called the "494" Autostar. Yes, you can computer-control it. I've done it.

You need the Meade 506 cable/converter kit, which plugs into the AUX socket on the telescope base. Whether you can find a 506 kit -without- a software CD along with it depends upon dealer stock. The CD Meade used to package (which had Starry Night Bundle edition) required three updates (two from Starry night, and one full ACP replacement ) before it would operate the ETX70 properly.

You might explore buying a 497 Autostar (-with- numeric keypad) on eBay or elsewhere... that will allow the use of a 505 cable kit (which is merely two connectors and a piece of wire... you can build your own, or buy them for as little as $6 on eBay). The 497 gives you more objects, easier numeric entry, access to Meade's free updates, etc.etc.etc. for not much more cost than the can-only-get-from-Meade 506 cable/converter set, which can NOT be home-built.

You might do well to join the yahoo discussion group:

and (of course) visit Mike Weasner's ETX megasite:


Subject: ETX Astro Dual Axis Drive Corrector   Top

From: Jordan Blessing <> Date: July, 1998

I would like you to consider adding my latest product, a dual axis drive corrector for the ETX Astro. I'm sure many ETX owners would be interested. The web address is:


Note that there is also quite a bit of content there relative to the ETX, not just a product link.


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