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Home > Reviews > Mounts > Equatorial > Meade LXD 750

Meade LXD 750
By Ed Moreno - 3/13/2008

Review, Meade LXD 750 German Equatorial Mount

So, you’ve lost your freaking mind and decided that you need a big German Equatorial Mount mount. What to buy, what to buy.

Well, if you have been curious about ONE of the choices, the Meade LXD 750, I hope that this review will provide you with some insight.

Now I didn’t BUY the Meade LXD 750.. In fact, it was not at all what I started out to get. Lately, I have been trying to do more “Trades” than buying and selling, and in search of a new mount for Buffy, my 20something girlfriend AP refractor, I recently decided that I would trade my old and trusted Vixen 140 (and mount) to get a GEM big enough for the old AP refractor.

I was actually looking to find a nice used G11 or Celestron Ci700 equipped with Digital Setting Circles. Both of these mounts would have worked well for Buffy.

No, that is NOT a CG5 next to the LXD 750...


Why not an Atlas or EQ6? Frankly, I don’t think these mounts are up to the task. I had an early version of the EQ6 and while I used it with a Meade 152ED, I came to feel that the mount was really just a bit under what that OTA needed. In my EQ6 review here on Astromart, I said that it worked “Acceptably well”, but in all honesty, I think that maybe the mount was not REALLY acceptable for the Meade 152ED, but rather “I just bought this new mount brand new, and I will live with it, so that makes it “Acceptable.” I was clear though in my review of the EQ6 that it was not nearly in the same class as even the old Celestron Ci 700.

See, refractors are much more demanding to mount than people think. The MAIN problem is that to use a refractor at zenith, you have to fully extend the legs on smaller mounts, and it is the TRIPOD that limits the mounts stability. The long lever of a set of lenses at one end and a 31mm Nagler at the other means that if you get it shaking, it will most likely CONTINUE to shake. And if you are looking at Saturn at 300x, you don’t want ANY movement. Even a small gust of wind will shake the view. For SCTs and Reflectors (where the mount is used with the tripod at its lowest height) the stability is FAR greater. So, the EQ6 to me was not enough mount for a telescope that I felt would spend much of its life doing very high power observing. Sorry, Atlas owners. No disrespect intended, but the Atlas is simply not really all that heavy a duty mount when you are talking big refractors.

Now the AP fully rigged (rings, dovetail, diagonal, Telrad, 2” diagonal, and 31mm Televue Nagler) has a full up weight that is only about 26 lbs. The Meade 152ED was perhaps closer to 32 lbs.. So an Atlas MIGHT have actually worked. Maybe… But frankly, the Atlas was not really much easier to take out than a CGE or Ci 700, so in the end, to me, the ability to have a STABLE mount at the cost of only slightly more effort meant that I was going to stick with a CGE class mount.

But none presented themselves. Life does that sometimes.

What DID present itself was a Meade LXD 750. I had no experience with this mount, and what I could find on them was somewhat sparse. Much of it was from imagers, and concerned tracking and those reviews were mixed. I myself am ONLY a visual observer, so this didn’t bother me so much. I have seen a BUNCH of pictures of the LXD 750, and I DO like the packaging. It is fully Go-to, and while I don’t NEED Go-to, I like the clean packaging over the Ci 700 and the G11 with DSCs, so the Go-to was icing on the cake.

So I made the deal. As it turns out, maybe it isn’t the right mount for me, but it IS an interesting mount none-the-less.

I have to start my direct commentary about the LXD 750 with this thought. I will confess to you that I think that the LXD 750 was a REMARKABLE mount in its day. I don’t think anyone have ever really given Meade the credit it deserves for having brought this mount to the market. Considering that this mount was introduced in 1992 (15 years ago) I have to say that I am ENORMOUSLY impressed at what it represented back then. And in my estimation, it holds up REMARKBLY well to more recent offerings.

So lets go down the list.

First, the mount was fully Go-to back at a time when Digital Setting Circles had only been mainstream for a few years. The computerized Go-to could be added as an option, or you could get the mount as just a non-computerized mount with drives in both axis’s. Can you say “Atlas?

Next was the packaging. I have to tell you that I am a BIG fan of the Atlas packaging. I love the fully enclosed motor housings and general de-clutter of the head in terms of not having cables all over the place. The LXD 750 (and little brother, LXD 650) are packaged extremely well. There is one cable for power, on cable for the handset, and one cable from the Dec housing to the RA housing. Again, it seems like the Atlas designers clearly got their inspiration from the LXD 750.

15 years ago, this thing was ULTRA-Modern.. Beyond leading edge I think. I mean I have to tell you, I am IMPRESSED by the design and packaging that was done 15 years ago.

And then there is the computer software. I am sure that the software went through several updates, but I have an early version of the manual, and trust me, Meade did an OUTSTANDING job (for the time, but I will discuss this in a bit more detail later on). By comparison, the first generation Atlas Go-To software was lame. After a decade of having the Meade and Celestron software to compare to, I was scathing in my review of the EQ6 when it came out for missing some BASIC features (What, no SYNC function?) that apparently Meade got on their first try! I have to tell you that as old as the software is in the LXD 750, it is SURPRISINGLY capable. But it has it’s limits, and I will talk about that more later as well.

Ok, lets talk BIG..

OMG! This thing is simply ENORMOUS. I used to think that the C1 700, CGE and G11 were big. LOL.. Fact is, my CGE is downright PUNY next to the LXD 750.

Remember, the LXD 750 was built for ONE purpose and ONE purpose only.. That was to hold up the Meade 178ED. It didn’t HAVE to be as big as it is to hold up the Meade 152ED, but to make it STABLE for the 178” f/9 OTA, the mount had to be strong. So this mount was designed to hold the giant 178ED high enough and steady enough to view at zenith. I HAD to be BEEFY. And it is… When you remove the cover for the polar scope, you can see the rear RA bearing. It makes the wheel bearings from a 1999 Mustang GT look tiny by comparison. These bearings are simply HUGE overkill. I would estimate that the RA bearings could support 1500 lbs each. Why in the world would you NEED such enormous bearings? I don’t know, but they are there. Anyway, the bearings are all mounted in these giant aluminum castings. The significance of this is that the box section castings are probably incredibly strong. Truth is, I don’t know WHAT the true limit of the mount would be, but let’s just say that for the money it represented a TRULY heavy duty mount that is EASILY a step above the CGE or the G11. It is THAT big and beefy.

I have never seen this mount marketed with any other OTA than the Meade 152ED or Meade 178, which is STAGGERING to me.. I can’t believe that while Celestron was marketing all of their big SCTs on GEMs, Meade let them have that market to themselves. I think that the LDX 750 might even have been able to hold the Meade 14” SCT with no problem (the Meade 14 inch is MUCH heavier than the Celestron 14 inch though).

Anyway, EVERYTHING about this mount is BIG. Take the “Meade Giant Field Tripod” for example.. Now this tripod I think actually comes in two leg lengths. I think the ones that came with SCTs had “Short” legs. But the one that came with the LXD 750 had longer legs than the ones that came with the SCT (I THINK. Not positive). The legs measure 45 inches in length from the ground tip to the bolt at the top (This is NOT the tripod HEIGHT, but rather the length of the legs). The legs are 3 inches in Diameter. By comparison, the CGE legs are 37” long and 2.75” in diameter. Now the legs on the Meade SEEM a bit thinner walled, but this is impossible to know. They SOUND thinner than the CGE legs when you tap on them, and while the Meade Giant tripod is a LOT bigger, it isn’t all that much heavier.

Anyway, the tripod is enormous. In fact, it is TOO enormous. For stability purposes (I GUESS, I don’t know for sure), the tripod was given an UNUSAULLY wide stance. This means that while the tripod LEGS are longer, in its original configuration, they had a huge spread, even with the legs fully retracted. Now I personally think that this spread was FAR greater than it needed to be, so I MODIFIED the tripod to reduce it.. More on that later.

Now one thing that keeps these out of the mainstream is that they were only ever shipped with cradles for the Meade refractors. To mount anything else, you have to get an adapter that allows the use of an aftermarket saddle. The person I traded with was actually kind enough to fabricate such an adapter, and I put a standard G11 saddle on it for my needs. Now the G11 adapter actually is the weak point here because it uses two ¼ inch stainless steel screws to mate the saddle to the adapter, but since the load factor on a single stainless steel 1/4 -20 screw is about 1500 lbs, I don’t think that anything is going to fall off.

Anyway, the point here is that this thing is a massive, heavy duty mount. I was stunned to see how heavy duty it really is. It MIGHT classify as the heaviest duty GEM mount that a single individual can “Easily” manage. I am betting that if you could solve the counterweight issue (the shaft is not all that long and the weights are tall and small diameter raising the center of mass closer to the RA housing), this mount could carry 80 lbs quite conservatively.

Ok, Get it? It is a big honking mount.




What is it like to use? Surprisingly, the more I use it, the more I like it.

Setup is somewhat straight forward with two exceptions, the first being that the head is physically bulky (and heavy of course, but not as heavy as it looks as compared to the CGE). The second exception is that the head, like the Atlas head (and I said the same thing about it too) can’t be stood on its base when you set it down. Well, it KINDA can, but with some risk.. See, on one side of the mount you have the slow Motion control knobs (Don’t function when the mount is in Go-To mode…) If you lay it on that side, you could bend a knob (not an issue with the Atlas which has no mechanical slow motion controls). But I LIKE the slow motion controls because they make the alignment setup a bit easier. Anyway, on the OTHER side, you have the RJ 11 telephone type connectors for the RA drive, and I worry that they will crack if the mount somehow lays on them. So finding a piece of real estate to put this monster down is not all that easy. The CGE can stand on its Mini-pier and sit on the edge of a sturdy table or dresser. Now so with the LXD 750. You BETTER have a place to put it down…

Now what I HAVE found is that you can actually stand the thing on end on the floor on the plastic polar scope cover, which is about the size of a one cup plastic measuring cup. It is pretty thick and sturdy, but I am not so sure that one day it won’t collapse. So, I don’t like this. I wish that the projection from the base was on the was on the TOP of the tripod and that the head was flat on the bottom so you could stand it up, but that is not the way it is.. Man, am I PICKY, or what. But keep in mind that I am a VERY active observer, and if it causes ME pain, you will LEARN to not like it if Eddgie doesn’t like it.

But once the thing is broken down, it actually takes only a TINY bit more physical effort to take out than the CGE. But the Tripod legs are SOOO long that even at my TOWERING, MANLY six foot stature, it is hard to lift it from the top and get clearance at the bottom for the freaking DOOR SILL… But it isn’t all that heavy.

When you get it outside, the tripod goes down then the head goes on in a similar fashion to the Atlas. It’s all just bigger and heavier.

There is a threaded rod with a spreader that comes up from the bottom and bears against the inside of the legs. Now I didn’t like this setup with the Atlas, and I don’t like it with the LXD. The problem is that you can apply massive amounts of torque to the spreader when you lock to head in place, and OOOPS, a BIT too much torque will cause the thin tube walls to dent. I prefer the plastic spreader on the CGE mounts to the Atlas and LXD spreaders. So, the people that “Cloned” the LXD 750 to make the Atlas copied the bad along with the good.

In either case, I still prefer the Meade tripod to the Losmandy stub legs. As big as and bulky as the tripod is, I prefer a tripod that folds to having to disassemble and rebuild in the field. Too many parts in the Losmandy tripod. Rock solid though. And to be fair, even when folded, Meade Giant Field tripod is a BIG thing.

Once the head is on, you can level the tripod. Now as it turns out, you DO want to level the LXD tripod. This is because the hand set software ASSUMES that the tripod is level. Now you COULD simply level East/West and just let the alignment deal with the altitude, but since you DO need to level East/West, well how much harder is it to level N/S.

After leveling, you can do weights and OTA.

Initial alignment is to my knowledge, unique to the LXD 650/750. At first, I didn’t like it, but after I lived with it a while, well, I still didn’t like it… LOL. See, the hand controller software seems to DEPEND on an accurate polar alignment. When you start the alignment process, you are instructed to move the Dec housing so that the side with the cable connections is pointing up and the retractable counterweigh shaft is level to the ground. You are also instructed to put the scope at 90 degrees declination. The result is that the scope is hanging off one side of the head. Once you have everything locked down and hit “Enter”, the computer will slew the telescope to Polaris. Now I don’t know what it will do if Polaris would put the scope UNDER the RA Axis (like in the summer), but for now, it is putting the OTA mostly over the top of the RA housing.

Once it moves the scope to where it thinks Polaris should be, you are THEN instructed to ALIGN THE MOUNT ITSELF (using the altitude and azimuth fine adjustments) so that you can sight Polaris in the eyepiece (and the manual recommends using a crosshair eyepiece).

When you have done this (and it can be a bit tricky if the giant washer inside the Altitude pivot is not tight against the head housing, it will shift when you tighten the beautiful, large anodized knob), you can press Enter again, and the mount will slew to an Alignment star. The bad news here is that you don’t get to pick the star. It picks one for you. And it seems to want to use one on the East side of the mount. The GOOD news is that so far, it seems to prefer stars that are reasonably high in the sky. You then align on this single star. If the star is blocked, you simply choose another star and align on it.

But here is the deal. I both like, and don’t like this. The idea is that the scope attempts to ALIGN THE MOUNT, and NOT simply calculate the error in whatever alignment the mount was set up in. And if the Polar alignment WAS off a bit, pointing will be BAD.

No it gets worse.. Because there is not a multiple, cross sky alignment (3 star), if your OTA has cone error, this is going to show too. To get my refractor to point really well, I had to do some tweaking. I had to put shims between the dovetail and the front ring to get the cone error fairly close in order to get really excellent pointing. This kind of error is called "Cone Error" and more modern mounts simply calcualte it out.

There is some good news as well though. The mount does make it VERY easy to go back and touch up your polar alignment. You simply press a couple of buttons and the mount goes back to the position that it thinks Polaris should be in. Once again, you tweak the MOUNT (don’t center using the handset).

After doing this a couple of times (and adjusting out the cone error) my pointing because EXTREMELY accurate, so there IS a payoff. And while My CGE will take less effort to align, for long term tracking (the CGE will drift out in declination if the mount is not accurately polar aligned), the LXD 750 actually may have a BETTER system for obtaining a very accurate polar align, and again, once done, the pointing becomes extremely precise. Clearly though, this is one area that the newer telescopes all excel at. You don’t need to be level, and if you are willing to do a three star alignment, you don’t need to adjust cone error. But I have to say, there IS merit to the “Adjust the mount” approach. Long term tracking I think is better, and when you DO get the cone error adjusted out of your OTA and the mount accurately polar aligned, pointing seems to be near perfect. Well, at least it is in the 6” F/8. I was doing double star work with a Meade 8.8 UWA as my “Finder” eyepiece and after I learned to get through the alignment and adjusted the cone error permanently, everything was falling into the field of that eyepiece.

The more I use the handset the more I do like it in general. I DOES have some EXCELLENT features. Once you are polar aligned, it won’t be needed, but if you aren’t getting really accurate pointing, you can choose the “High Precision Pointing” function.. With this, you simply pick your target and the mount will slew to a bright star in the area. You use the handset to align on the bright star, and from there it will home in on the target.

The mount also has a “Sync” function so if you just don’t really want to do an exact alignment, you can use bright stars in the general vicinity of your target to improve your pointing for that area of the sky.

I also like the way you can filter targets from the catalog. You can filter by horizon limits, which I particularly like. I have a lot of trees and obstructions, so I can’t really get to anything closer than about 20 degrees to the horizon, so I don’t need to see them in the catalog.

In the catalog, you also get to filter by “Quality” of the target. On one menu, there is a series of letters. Selecting the “VG” for example, and then using the on-line catalog, the telescope will limit its “Start Find” catalog search to objects that have a rating of “Very Good”, “Excellent,” or “Super”. This is a VERY nice feature. If you lower it to “Good” then everything from that category and above is presented in the Start Find catalog function.

The “Start Find” function itself organizes objects into “Strips” in the sky. If you don’t know what you want to look at, you can choose this option, and it will tell you what the next closest item is to your location in that strip of sky. If you want to go to that object, you simply press the “Go-to” button. There are also little bars in the handset that tell you how far in declination and Right Ascension the target is away.

Now one thing really bothered me. When I got the mount, I read the manual and it seemed to indicate that to go to bright stars, you had to know a freaking CATALOG number. This is only partially true. In fact, there IS a way to show the star names of the Alignment stars. You press the “Star” button, then press the “Enter” key, and rather than prompt you for a number, you are given the option to use a star name. Now the list is not as complete as on the CGE for example, but all of the bright stars in the sky seem to be crossed to a name. Find the name and hit “Go-to.” This makes me feel a bit better, but I wish the named star catalog were a little deeper.

Entering a manual coordinate is VERY easy. Now if you are a double star observer, you will appreciate this capability. I know that this is where you most need to enter manual coordinates, and I find the LXD 750 to be superior to the CGE and the Meade Autostar in this function. The ONLY thing negative here is the upside down number location layout of the keypad. “0” is in the lower left hand corner of the hand set, with “123” across the bottom and “789” across the top. This is “Proof” keyboard style (used in financial calculators and old touch tone telephones) but almost everyone now uses “123” across the top now. But hey, this thing is 15 years old.

I have to say, the more I use the LX200 controller (I think this is the generic name for it), the more impressed I am with it. While I wish it had a 3 star alignment, I otherwise have to compliment it on being an extremely powerful and practical handset design. I actually LIKE using it. I prefer it MUCH more than I did the Autostar handset. Man, Meade really got it RIGHT when they introduced the LXD 750. Why did Synta have such a clear miss when it introduced its EQ6? Even after 15 years, the Meade software works WELL. Not as easy to learn, but for an advanced astronomer, there are a lot of really excellent features. SOMEONE at Meade was a PRACTICTAL observer when this was designed, and it shows. But they were old school polar alignment people, and this shows too.

Practical considerations??? Well, as you might have imagined by the early descriptions, when observing, the thing is like tying your telescope to telephone pole. We are talking a pretty Rigid experience here.. I like it.. I LIKE it a LOT. The one thing that a high power telescope observer really WANTS is a solid, unshakable mount. And the LXD 750 more than surprised me with its capability. I had no freaking IDEA that this mount was so sturdy.

Slews are COOL. The mount is noisier than the CGE, but not much. In exchange for the small extra amount of noise, you get REALLY STINKING FAST SLEWING. And unlike the CGE or similar mounts (Including the LXD 75), this thing doesn’t overshoot and come back to the target. I believe this is something to do with the fact that servo motors are being used. Anyway, the CGE and similar mounts tend to always approach the target in the same direction, so that means that they stop short of the target and sometimes back up or creep in. When you press the “Go-to” button on the LXD 750, get out of the way, because this thing is going to move FAST, and when it gets to the target is simply STOPS. Within a second, a small “Beep” tells you that you may proceed back to the eyepiece. I LOVE the way this thing SPRINTS to the target and locks on like a Sidewinder off of an F4-J tracking a MIG 21! VERY cool stuff.

Earlier, I mentioned the giant footprint. I found it objectionable. The Assistant Astronomer was MORTIFIED when I set it up in our Garden room (which also serves as telescope hanger). I mean the legs spread half way across the room. CLEARLY there needed to be a change. I even was struggling with it thinking “What have I DONE!”

The solution was simple. I purchased some 1/8 inch steel strips from the local home improvement store and cut them to 14.5” lengths. I drilled holes 1/4th inch in from either end, and I replaced the factory spreaders (very nice anodized aluminum ones I might add) with these shortened spreaders. To make the top spreader lower, I purchased a stainless steel threaded rod to replace the factory rod, This allowed the spreader to come down more so that it could fit inside the taller triangle.

Now the benefits are two fold. First, it GREATLY reduced the footprint. The mount now has a footprint only a couple of inches bigger than the CGE. This is a good thing. The Assistant Astronomer was MUCH happier. I was too. Walking around those long legs was so tiring. It was that big!

The next benefit, if you are a big refractor owner, is that the narrower stance RAISED the saddle so that it isn’t necessary to extend the legs. I can use my 6” AP f/8 refractor with the legs fully retracted and get to the eyepiece easily by only slightly lowering my observer’s chair. Now this is a GOOD thing for me, because it is just one less step to take. Bad side is that I don’t know if I could lift the C14 up there. The saddle height was closer when the tripod was spread out more. But I CAN use the 6” on the CGE, so if I am lazy and want to take out ONE mount, but get the feeling that I might want to swap OTAs (sometimes I leave a mount set up outside but covered for several days in a row) than I can take out only the CGE. But honestly, I most typically use two telescopes at the same time, and I see a lot of nights where I will be taking out both mounts. It IS a lot of work, but when I observe, I typically spend fro 2 to 4 hours, and I like the flexibility that having two telescopes set up at the same time gives me.

I think this modification also makes the mount look more “Balanced” The original spread made the thing look like the Lunar Landing Module because it was so squat. Now it looks “Proper.” And I can put it back like it was so that anyone wanting to use it for something like a C14 could easily restore it. But I like it the way it is now.

Gotta tell you, I really like this mount. I really am amazed that not so much is known about these. At the used prices, thay may constitute one of the best mount values in astronomy. It is AMAZING that these mounts have been around for 15 years and so little is known about them, and that they are apparently GREATLY under-appreciated (as for tracking for imaging, I have to tell you, I have been inside, and the gear-work LOOKS to be high quality, and the handset allows for sophisticated PEC correction and even for DECLINATION DRIFT correction!!!).

Finally, it comes to this though.. Most people simply don’t NEED a mount this stinking big. And that is why I said at the beginning: maybe it wasn’t the right mount for me. It is overkill. No doubt. It is simply bigger than I need. But something about it makes me WANT to keep it. Does that sound odd? I mean I like the way it WORKS! And I really don’t think that it is THAT much more trouble to take out than the CGE. Jeesh, I can’t believe I am saying that.. Maybe I HAVE lost my mind.

If you were going to do a double saddle, or if you wanted to mount something like a big Newtonian reflector, you would do EXTREMELY well to consider one of these mounts. When I look at the engineering here, I simply have to tip my Resistol to Meade. This WAS a SUPERMOUNT in its day, and even by today’s standards, at current prices, if you NEED a BIG STINKING MOUNT, there simply isn’t much out there that can do what the Meade LXD 750 does for less than maybe four times the money..

Meade, you impressed me. Doesn’t happen much, but you sure did. You should have made it an option for your SCTs… Too bad that you abandoned this line. With refinement, this mount would be in a class of its own today.. Heck.. in fact, it IS in a class of its own.

If you need a BIG STINKING MOUNT, with software that STILL leads the pack in many ways, but don’t want to break the bank, I would say that the LXD 750 might just fill the bill. Recommended. A surprising value, and a darned good super-duty sized mount.

My regards…

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