Last updated: 19 January 2004
Subject: Niall's Demon ETX Date: 1/16/04, 12:32 From: Don Sutherland (email@example.com) Niall Saunders seems to have been cursed with the ETX from hell. The fact that his scope has no hard stops on the Az axis is an indication that something is SERIOUSLY wrong. Something is broken or missing entirely. I doubt Meade would hesitate to give him a new scope for this reason alone. Niall mentioned that the black and blue (how fitting) wires to the Dec drive are visibly damaged. In addition, the strands of wire inside the insulation of the four wires to the Dec drive may be broken from rotating the Az axis 3 turns each way, causing intermittent contacts and alignment failures. I do a lot of troubleshooting as a part of my job. If I can't find the cause of a problem, it is usually because I have overlooked or ignored something obvious. Niall's ETX has no hard stops. As a result, the wiring to the Dec drive is damaged. This is a no brainer! Return Scope to Meade for warranty replacement! Regards, Don SutherlandAnd this:
From: Bruce Hi Niall I saw you problems on Mike Weasner's site. I have a '105, and some comments might be in order. I presume you intend taking pictures (that's why you are polar aligning the scope), and that you are using an Autostar. If you don't plan to take pictures, don't bother with polar alignment. 1. Hard stops on RA axis. My (early) ETX105 has them. I get about 3 turns, stop to stop. I have seen a reports of these being broken on various models, so you do need to check this with Meade.... But don't hold your breath. Try emailing firstname.lastname@example.org - you might be lucky. 2. Home position. The altaz home position is with the control panel pointed to the west, and the tube level and pointed north. I don't know what the home position is for polar mode (I've read it on Mike's site, but haven't verified that it works.) In case it helps, home position for the LX200 is with the scope pointed at the intersection of the meridian and the celestial equator. 3. Alignment failed - this is caused by having the wrong angle (i.e. segment of a great circle) between two alignment stars. The scope can't work out where it is on the world, and gets confused. 4. As far as I know, the polar alignment routine only requires alignment to Polaris (by adjusting the wedge) and sync on a single star with RA ~6h different from the RA of Polaris. It does not need two stars to work - ergo I think your scope is trying to do an altaz alignment while mounted on a wedge. A polaris / single star alignment routine is pretty useless anyway, since you frequently can't see through the eyepiece, and it's nowhere near accurate enough for photography. I suggest you use the approach offered by Bruce Johnson (see http://members.aol.com/ccdastro/goto-tests.htm). I have tried this and it works like a charm - I find it's as good as drift alignment and _much_ quicker. (It was intended for the LX200, but the ideas will apply to any goto-scope.) 5. MUF - this usually indicates bad power connections or low supply voltage. Since you are running on an external supply, make sure that it can source enough current - if it can't, the voltage will drop and you could create a MUF problem. FWIW, I have an external supply that produces regulated 12VDC @ 1 ampere, and this seems to be fine. I have also seen an MUF failure when my ETX was significantly out of balance, and when I had a dud Autostar cable. If you have a camera mounted or are using 2" eyepieces, I suggest you balance the scope carefully; since you're a computer person making another Autostar cable should be a doddle - just check the order of the connections. 6. Easy align - I have had mixed experiences with easy align. One scope I had to fix (LX90) wouldn't do it properly; otoh, mine does - I don't know why. I recommend you use Paul Rodman's BestPair II to pick alignment stars - http://www.ilanga.com/bestpair/index.shtml/index.html and do it manually. 7. Finder - yes these are bloody awful, and a complete waste of money. Perhaps you should bin yours and get a unity power finder. I use a Telrad on my 12", and it's much more convenient than the finder, although you might think of something a bit smaller for the ETX. Hope this is a helpAnd:
From: Niall Saunders (email@example.com) Many, many thanks for your kind thoughts and comments. Yes, I AM trying to do digital astro-photography and, in any case, it just seemed more 'natural' to run the scope in Polar-Mount mode, if only because only one axis had to be driven. However, as my timed exposures can only be 16 seconds maximum (for as long as I continue to use my current camera) then perhaps the advantages of Polar mode are not really worthwhile. After all, I can always 'rotate' any captured images as required. Currently, the dealer who sold the telescope last year (it is still under warranty, purchased from f1cameras.com) has been FANTASTIC. He is arranging for the entire scope to make a round trip to Meade - either for repair, or replacement. What I was really (originally) looking for, and everyone who has replied seems to be confirming this, is whether (or not) the ETX-105 should have had RA/Az hard-stops. After all, there must be other users that (like us) depend on the huge amount of information exchange provided by Mike's fantastic site. It appears that I ought to have end-stops, and I don't, and the DEC/Alt feed cables have been badly damaged because of this. So, others - BEWARE!! Your comments on 'using' the scope are also very useful. Despite NOT having hard-stops, I do NOT think that the damaged cables should be causing the problems I noted the other night. As far as Polar Home position is concerned - I have been setting the OTA in the forks, such that the OTA is pointing AT Polaris (with whatever 'Kochab Clock' offset I can manage). This means that the OTA is effectively 'aligned' with the forks, and I also make sure that the forks themselves are 'parallel' with the ground. To me therefore, all that is now needed for the scope to operate correctly, is for the Autostar to move to a given RA/DEC coordinate, and the target SHOULD be in the FOV. After all, the Autostar KNOWS the correct Lat/Long and Local (UTC) time, and it KNOWS that it is currently pointed at the North Celestial Pole. If I have been 'accurate' with the setup, then virtually NO ALIGNMENT should thereafter be needed. If I did an Alignment in any case, I would have hoped that the Autostar would have just been removing any small errors 'left over'. But, when the first alignment star is not even in the FOV of the FinderScope, it makes you wonder what is happening!! I need to spend MORE time trying to analyse what is happening - and this is just eating up my viewing time. Hence the irritation. It is a shame that Meade don't release some sort of 'flow chart' that might explain to users what causes some of the problems to appear (MUF, Alignment Failures, Proc Trap 2, etc.) I understand that the detailed code is 'intellectual property' - but 'bugs' (if they exist) could be ironed out with constructive feedback from users. I haven't looked at your two suggested links (yet!!) but will do so later today/tonight. With a little luck, the roar of the rain outside (reminding me of the Monsoon's first rain in Kenya, many years ago) will eventually clear the air, and we might get a clear sky sometime soon!! Then I can try things again. As I said, in the meantime I am trying to hang on to the faulty scope for one more observing session, so that I can try and identify what is causing my problems. That way others can benefit, via Mike's site. I am also going to look at powering the scope in a different manner - just in case THAT has been part of the problem. Again, the internal wiring does NOT inspire confidence. Even though current consumption is low on these scopes (at MUCH less than 1000mA) I am not entirely convinced that induced voltage drop (due to internal wires being too thin) is NOT part of the problem. Why Meade went for a groove down the side of the DEC/Alt mounting bolt, as opposed to a hole bored through the same bolt is not immediately clear. That said, they could have quite easily machine FOUR grooves in the bolt, and allowed for larger wires AND thicker insulation. They could even have used 'extra flexible' silicone-sheathed wires and the cost could only have gone UP by a few dollars. And the FinderScope and/or balance issue. Yes, at the start of my evening of problems, I was using my trusty 'Rifle Scope' - mounted on the front end of the OTA using Velcro bands and some small patches of anti-slip rubber matting. It was certainly a huge improvement on the Mead unit, even though the scope is only a 6 x 40 device. The image was MUCH brighter (due to the larger aperture, and the lack of grease on the eyepiece) and it was MUCH more accurately aligned - due the accurate windage and elevation setting screws that a rifle-scope provides. But I removed it when I dismantled the scope mid-evening, just in case 'balance' was an issue. I had hoped to counteract the extra 'nose' weight when I attached my digital camera - had I ever been able to track successfully that evening! I will 'start again' if I get a replacement RA Finderscope once the unit is back from Meade. So, now all I need are clear skies . . . . . . Cheers, Niall
Subject: RE: ETX-105 End Stops and Problems - a continuing saga Date: 1/14/04, 18:38 From: Niall Saunders (firstname.lastname@example.org) Sorry it has taken so long for me to respond to your kind emails - but I have been trying to actually USE my ETX-105 whenever the dreadful weather conditions we are experiencing here in Aberdeen permit. However, tonight was the last straw. Thankfully I surrendered my shotgun licence a few years ago, otherwise I PROMISE I would have blown the useless piece of junk clean off its tripod. I consider myself thoroughly computer literate, I have a degree in Electronics and studied Astrophysics at M.I.T. - I can dismantle a C.D. player, replace its laser and recalibrate it; I can take a mobile phone to pieces, locate a faulty surface mount component and replace that, I can program microcomputers, microcontrollers, FPGA ASIC chips, and can even get Microsoft Windows to behave; I can align a fully stabilised 2.7m communications dish to a geo-stationary satellite in orbit, whilst on a vessel at sea, rolling +/-20 degrees in all three axes; I can strip and rebuild a V8 Landrover engine (and its gearbox and transmission); and I can Gas, Arc, MIG and TIG weld; and I can operate a Lathe or a Milling Machine. But the ETX has me beat. Tonight we had about 5 hours of PERFECT skies - in between two frontal systems that otherwise wiped everything out with 100% cloud cover. Using a fifty-year-old 4" Refractor on an Alt-Az tripod made from little more than 6-foot long 2"x1"'s I was able to marvel at all three major rings on Saturn; one of the nicest views I have ever had of M-42 in Orion; M-57 was so obviously a 'ring'; the Andromeda Galaxy (M-33) was breathtaking; Ceres-1 could be seen in Gemini, as could the Eskimo Cluster; and I could 'split the doubles' in Epsilon Lyrae. But the ETX-105 took TWO HOURS to TOTALLY FAIL in all alignment attempts. Firstly, I use a DIGITAL INCLINOMETER (accurate to 0.1 degree, and in FULL CALIBRATION) to set the top of the #887 De-Luxe (ha-bloody-ha!!) Tripod to be LEVEL in two orthogonal axes (by adjusting leg length). At the same time I will have set the 'leading leg' to as close to Celestial North as I can manage. I raise the tripod 'wedge' to a HIGH elevation, as this tilts the whole scope forward, allowing me to place the digital inclinometer across the rear faces of the forks, thus guaranteeing that the forks are parallel to the ground, and also therefore orthogonal to the earth's polar axis. I then lower the 'wedge' back down to the compliment of my Latitude 32.8 degrees(complimenting the 57.2 degrees for my home address - which I know to within 3m accuracy from Differentially-Corrected GPS readings), and which I can set to within +/- 0.2 degrees accuracy with the aid of my Digital Inclinometer (I can't get the angle any more accurate, because the Deluxe Tripod is too cheap to offer anything more than the coarsest of adjustments, but I try my best). I then tilt the OTA such that the body is at the same angle as my Latitude (and I double check by taking a reading of the complimentary angle across the face of the objective end of the OTA). I can't use the Meade (or similar) instructions to otherwise set the POLAR HOME position - because my ETX-105 absolutely, positively DOES NOT HAVE END-STOPS. (and I have checked by rotating the base THREE FULL TURNS anti-clockwise, followed by SIX FULL TURNS clockwise, and then back to the mid-point with three more turns anti-clockwise. There is no end-stop, nor any hint of such. As prompted by the proprietor of the dealership that supplied the scope, I had already removed the three rubber 'feet' and had looked inside the base assembly. I was horrified by the state of the twisted Az/Dec feed wires. The black outer sheath had 'knotted' itself up, and then subsequently had 'split' a few millimetres from the RA/Az axis bolt. The blue wire had even had its insulation stripped - although fortunately was not rubbing against anything. So, having seen this, I knew that I must always be 'conscious' of how many AZIMUTH turns the scope was making, always ensuring that either the Autostar, or me, 'unwound' the scope back to the position I had left the wires in prior to refitting the base assembly lid. So, the process described is the one I have to use for initialisation. With the Autostar and power still disconnected, I check my polar alignment using the 26mm lens (57x magnification, approx 1 degree FOV). If I am lucky - and I am usually NOT !! - Polaris 'might' be in the main FOV. I cannot use the 8 x 25 R.A. viewfinder, it is utterly useless. A plastic scope from a Christmas Cracker would work better! The finderscope ONLY focuses in the centre 1/8th of the 7.5 degree FOV. This appears to be due to a film of grease covering the entire eyepiece, as a result of the viscous lubricant used in the focussing ring. I dare not clean it as I am concerned that anything stronger than heavy breathing might dissolve the finderscope completely. So, I probably need to adjust the scope to centre on Polaris. Forget about using Kochab's Clock or anything that sophisticated. Just getting Polaris into the main FOV must be considered a successful evening's entertainment. If I am REALLY LUCKY, I might just need to compensate in declination (Azimuth). On the basis that I feel the Autostar will want to 'start' from the 'Home' position I do not touch the OTA, and instead I adjust the elevation rod on the #887 Tripod 'wedge'. I am getting 'good' at putting in 'fine adjustments'. But, if I need to adjust 'sideways' the the polar-oriented RA/Azimuth axis is of NO USE to me (apart from the fact that I don't want to adjust the 'HOME' position). So, I have NO ALTERNATIVE but to physically move the WHOLE TRIPOD (because Meade were to 'tight' to offer an azimuth adjustment on their 'deluxe' scope). Now, of course, I have to consider the 'level' of the tripod all over again. I have decided now that I will ONLY adjust the two 'lateral' (East/West) legs when trying to 'centre' Polaris (as far as 'azimuth' in the viewfinder is concerned). If I can get the tripod adjusted to have Polaris 'centred' (in Azimuth at least) AND I have the tripod top plate 'level' (in the 'East/West' axis anyway), THEN I see no reason why I cannot use EITHER the 'leading leg' of the tripod OR the 'latitude adjustment rod' to get the base of the ETX set to the correct angle (this being the compliment of my Latitude). So, I choose to use the latitude adjustment rod, because this is easier to do when looking through the eyepiece. So, anything up to an hour after first going outside, I 'should' have Polaris centred in my 1 degree FOV. At least the delay allows the scope to settle into thermal equilibrium. As I said, Kochab's Clock - forget it. Polaris ANYWHERE in the FOV is often the best I can manage. Now I power up. I am running from a 12V 17Ah, fully charged 'Porta-Power' pack. If this can start my V8 Landrover it can surely run my itty-bitty ETX scope. (I have tried running 'direct' from the 12V battery AND from a LAB-QUALITY 12 mains power supply unit - what happens next is basically the same) I enter the date, and the time - accurate to the nearest second from my GPS receiver. And I will have entered my Lat/Long from the GPS as well - although I am surprised that the Autostar doesn't ask for the position in any greater detail. I select Daylight Saving Time as "OFF" (although I experimented with the "ON" setting just to see what the difference was - a 15 degree 'sky error' just as I would have expected). And now the REAL FUN BEGINS. I ask for an EASY ALIGN, and off the scope slews to PROCYON (obviously the Autostar's favourite choice for my location, my viewing time, and this time of year). However, when the glorious fanfare is eventually sounded by the Autostar, I can usually see that the OTA is 'miles off' - looking up the OTA I can see that Procyon is off by the 'width of the OTA' (or about 5 degrees of arc). I have tried TWO things at this point. One is to use the slew buttons to get the OTA 'on-line', the other is just to physically move the OTA, by hand' until I get Procyon centred. Nether two methods seems to make much difference thereafter. Then I press ENTER as usual, and off we go to Aldebaran. Again I can expect up to 5 or so arc-degrees of error, but now I feel that I HAVE to use the slew-buttons to get Aldebaran centred. Finally I press ENTER again, and hold my breath. I don't know why, because the usual response is ALIGNMENT FAILED, and I have to go all the way back to Polar Home once again, and start all over. If I am TRULY lucky, I 'might' get an ALIGNMENT SUCCESSFUL, not that it does me much good, because any subsequent GO TO's will usually only put the target in the (un-useable) FOV of the Finderscope, never in the FOV of the OTA.. If I manually slew to centre something like Saturn, then sidereal tracking is all but hopeless. A few minutes in a low magnification eyepiece is the best that I have ever achieved. However, tonight the gremlins truly conspired against me. As the night wore on, I started to get 'MOTOR UNIT FAULTS' as soon as the scope started to slew toward Procyon - always in roughly the same position of RA/Dec. So, unwillingly , I resorted to the RESET; CALIBRATE; TRAIN DRIVES routine that Dr. Clay recommends. I did SEVERAL of these - to no avail. I then did DOUBLE RESETS, followed by DOUBLE CALIBRATES, followed by DOUBLE TRAIN DIVES (and I knew to make sure that I was training BOTH axes, although the Autostar 'user interface' at that particular - critical - stage is ABYSMAL). I checked 'Battery Voltage' - it was at 100% (actually 12.867V by my calibrated Digital Multimeter - surely a 'digital' readout could not have been THAT difficult to implement on the Autostar???). The outside ambient temperature was just around freezing, with frost on the grass, but the Autostar had been in my hand for the better part of two hours by this time. So, with no access to my shotgun, I decided to get the system 'opened up'. I virtually no longer cared about my warranty - if this was the best that Meade could supply by way of Quality Control, it seemed unlikely that they could do any better 'second time around'. Although I had suffered numerous 'M.U.F.s' when running the DEC/Alt axis at full slew speed, when I opened the base the DEC/Alt wires, previously seen as 'damaged', seemed no worse - although I decided to strip the damaged outer black sheath to relieve the strain, just in case. This time though, I also decided to look more closely at the RA/Az motor and gear train. The first thing I noticed (apart from a generous spray of 'Mexican Green Goo' everywhere) was that ALL THREE screws holding the drive assembly to the chassis were VERY loose - one screw was only just staying in place. I CAREFULLY tightened these, as it was obvious that ANY excess force would strip the thread out of the cast alloy base. I also could 'just' see that there was green grease around and about the plastic wheel that serves as a position sensor for the gear train. So I removed the two screws holding the drive PCB in place, and watched BOTH of the IDC connectors FALL OFF their header pins (the four-way connector feeding the Autostar AND the two-way connector feeding the motor). Fortunately I had already sketched their locations (blue wire to the 'inside' of the PCB on the 4-way, and black wire to the 'inside' of the PCB on the 2-way). I carefully 'rearranged' the header pins so that, when reassembled, the artificial mis-alignment would serve to make a firmer connection. Using methylated spirits (I couldn't be bothered to find my Isopropyl Alcohol, and I was already drinking the Single Malt, and wasn't going to waste THAT on this mickey-mouse gearbox) I cleaned all the mexi-snot off the sensors, and also off the slotted disc as well. I also removed a good half-teaspoonful from the remainder of the gear-train as it seemed that the Mexican assembly line instructions are to "use plenty, and then add a good dollop extra, just for good measure". Then I removed the two little screws from the inside of the fork that contains the DEC/Alt drive mechanism. I also removed the 'knurled clamp' and the 'non-enumerated' disc to reveal a further, slightly longer, screw that, when removed, allowed the outer cover of the fork to be removed. It was at least nice to see that the ETX-105 does use a LOT MORE cast alloy than its predecessors (the ETX-90 and ETX-125). There seemed to be little evidence of 'grease spatter' on the DEC/Alt mechanism - such that there was did NOT seem to be getting anywhere near the slotted disc, so a brief clean (and another sniff of the Meths) and all was deemed 'OK'. What I did do was to thoroughly 'de-oil' the little brass ring that sits between the large aluminium disc and the DEC/Alt bearing. I felt that the 'less' lubricant on this item would lead to 'less' force required to 'clamp' the DEC/Alt axis (especially useful if trying to load a digital camera onto the OTA). The DEC/Alt 'clutch' IS in fact this little brass ring - which is clamped down, by the knurled knob, between the large aluminium (graduated but non-enumerated) disc and the inner race of the ball-bearing. So, feeling that I had addressed SOME of the obvious faults on the unit, I went back outside (two hours of 10/10 viewing had elapsed !!) and tried to re-align on Polaris (after taking the time to RESET/CALIBRATE/TRAIN - AND to ensure that ALL of the other parameters had been correctly set: Scope Type, Scope Mount, Site Location etc. - and to record that the Autostar software is 2.6Ec). The Autostar started off towards Procyon for the Easy Align and, at the same point as before, ANOTHER damned M.U.F. - this time I just stopped the OTA where it was and worked BOTH axes (individually and together) at FULL slew speed back and forth (360 degrees in Azimuth, 90 in Altitude). I did this for TEN MINUTES, with no further MUF's. Back to the beginning again - although this time I could hardly see Polaris because the clouds were now rolling in. And then off to Procyon - but, when the OTA got there, Procyon was GONE. In fact the WHOLE sky was now obscured - except for a small patch just visible up the side of my house - where some unidentified star had just climbed out of the Eastern horizon. I tried to slew to the star, hoping to see if the Autostar would at least manage some form of sidereal tracking - only this time I encountered (for the FIRST TIME) the 'creep after slew' and 'rubber-banding' issues I have heard others describe. I gave up in disgust. Despite everything being reasonably damp I couldn't even be bothered to take my normal 'dew' precautions, and just heaved the whole (expletive deleted!!) sorry mess into my hallway - pending further disposal measures. My question now is : "Am I doing something wrong, or am I just stupid?" And, by the way Mike, I have read EVERY SINGLE page of your site - and the LDX site - and most of Dr. Clay's pages, AND the whole of the Meade site (including downloading the 300Mb of their 2003 catalogue in PDF format) and so feel that I am covering MOST, if not ALL of the 'common mistakes' that new ETX users make. If you decide to 'publish' this lengthy 'grumble' (and you have my permission to do so) then all I ask is for someone, anyone, to let me know if I am making some un-noticed fundamental mistake when trying to use my ETX. Failing that, then I dread hearing the standard response of 'back to Meade it will have to go'. Thanks in advance. Niall SaundersMike here: Sorry you are still having problems. First up, the missing hardstops. I still think you need to contact Meade about that. If no one reports such a problem how will they know about it? It could be a one-of-a-kind occurrence OR it could be a faulty batch of them. Meade needs to hear from you. Assuming the lack of hardstops isn't part of a larger problem, then you may be "over-engineering" the process. Lets start with the basics. Forget Polar Mode for now. Forget about the levels and GPS. Pick a city nearby. Set up in the Alt/Az HOME position (eyeballing the leveling). Do a 2-star Easy Alignment. Does that work better? What about 1-star alignment? Let know me know.
Thanks for getting back to me so quickly. You are absolutely right about going 'back to basics', and that is exactly what I intend to try on the next clear night. Prior to that I will do a full Reset (again), followed by a Calibrate and Dual-Axis Train Motors routine (ensuring that this time I am in Alt/Az mode). I will feed back my results. As far as Meade and my Dealer are concerned, I have spoken briefly to Meade to ask about their returns procedure, and at length to the 'original' dealer - who has been more than helpful (Mr. Papagno, of F1Cameras.co.uk). It would seem certain that the scope will be making a trip back to Meade (fortunately without the 'shotgun' evidence!). In the meantime, could anyone perhaps contribute to what scenario actually causes the "Alignment Unsuccessful" error message? (Perhaps the same question could be asked of the "Motor Unit Fault" message, although I am going back to re-read some of the Technical Information already gleaned from your site - I seem to remember having come across THAT answer before!) Once again, both myself and the ETX community are indebted to the service your site provides. Niall Saunders Aberdeen, ScotlandMike here: See the article "Motor Failure Error" on the Autostar Information page. "Alignment Failed" occurs when the geometry of the centered stars doesn't match what the Autostar expects. It typically occurs when the wrong star is centered during the alignment phase. It can also occur if there is a bug in the Autostar database (known to happen). Selecting a different alignment pair can help that one.
I am spending a few minutes on the Cloudy Nights website, then I'll be back to yours for another 'marathon session'. Who says learning stops when you graduate? Cheers, Niall
Subject: First Time Novice Observations with the ETX105 and a reply to Nick Preece Date: 1/9/04, 18:40 From: Larry Somers (email@example.com) Nick, Like you, I am new to telescopes. After doing my research and finding Mike Weasner's great site, My wife and I went ahead and purchased an ETX 105EC with UTHC, Autostar Controller, & 884 Tripod, for Christmas. I found that setting it up initially and training the motors was actually very easy but essential prior to first use. Youll want to do this during the daylight! The one thing I found confusing was how to align the scope. The instruction manual, the tripod manual, and the Autostar manual all give instructions on alignment. I was confused which method to use? So my first attempt polar alignment resulted in what seemed to me to be a very unsteady telescope. As I was unconvinced that I had done this correctly I drove on down to the local telescope store (Oceanside Photo and Telescope) and asked if they could quickly show me. Basically, it took them all of about 2 minutes to show me the correct way (Alt/Az) for easy alignment with Autostar. So, I suggest, have someone familiar with the ETX show you and/or follow the Autostar manual. The Easy Align is very easy and the way to go to get started. So that night, New Years eve, around 11:30 PM, I brought the scope outside and did my best to align the ETX following the Autostar Easy Align instructions. Basically all you do is 1) level the scope, 2) point it North (Home position), 3) engage the horizontal and vertical locks, 4) Tell Autostar to align the scope. My backyard faces south, so I couldnt see the north star, and I didnt have a compass, so I only guessed on pointing the scope north. I then told Autostar to do its stuff (Easy Align) and, to my amazement and luck it automatically slewed to Polaris in the southern sky. I didnt know it was Polaris but I just followed the directions and centered the brightest star I saw in that region of sky in my telescopes eyepiece, and told Autostar it was centered. Autostar then automatically slewed my scope to Aldebaran in the South West, I again centered the brightest star in that region of sky in the scopes eyepiece, told Autostar it was centered and tada the scope was aligned! Not believing it could be that easy I then told Autostar to GoTo the moon. Again, to my amazement, the scope slewed automatically to the moon right on! After viewing the moon for some time, at midnight I tried the ultimate test and told Autostar to find Jupiter and then Saturn. Again, to my amazement, the scope slewed immediately to each planet. I could make out some banding on Jupiter and the rings of Saturn using my 26 mm eyepiece. After focusing on Saturn, I replaced the 26mm eyepiece with an inexpensive 6 mm GSO eyepiece. Immediately the planet disappeared from view and I spent about a hour finding and refocusing the telescope on Saturn. Autostar is of no help at this point. It was difficult to focus perfectly because even touching the focus knob moved the planet out of the field of focus. Also, since the 6 mm eyepiece is much shorter then the 26mm eyepiece, the longer eyepiece of the spotting scope, which is mounted just to the left of the eyepiece, makes it difficult for you to view with your right eye. After refining the Autostar tracking a few times the scope tracked the plant perfectly until we were ready to stop for the night. I was able to just make out the division in the rings of Saturn but thats all. I am hopeful that a better quality eyepiece will give me better results in the future. I think the biggest reasons for my success were: 1. Training the telescope during the daylight an easy task but one I suspect is most critical to getting Autostar to work correctly. 2. Learning the correct way to align the scope (Easy Align). This is very easy but because there are several different ways to align a telescope it is easy for 1st timers to get confused. 3. Learn how to tell Autostar to refine the alignment once you focus on an object. This really improves tracking of the object. The Good & the Bad of the ETX 105 my opinion! I would appreciate the views of Mike and others regarding these items. The Good: * Optics: The optics of the scope seems to be superb. The moon and its creators are sharp as a tack with no color fringes that Ive notice. * Autostar seems to work great if the scope has been trained and aligned correctly. Just what the novice (me) needed to start finding objects. * 884 Field Tripod: Solid and well matched to the 105EX. This is important as the slightest movement of the scope, when observing with a high power objective, will cause the object to move out of the field of view. * Portability. Because we have a small back yard with a fence around it I wanted a scope I could hall up the mountain near our house. This should be no problem with the EX 105. The Bad: * Vertical Lock: I find the Vertical Lock on the ETX scopes to be its most serious week point. Its essential that the scope be vertically and horizontally locked to engage the motor drive. With such a good tripod, the last thing I expected was that the fork mount would not hold the scope steady! The Vertical Lock does not secure the scope from up and down movement very well. The result is that the user tends to over-tighten the vertical lock trying to make the tube steady. I checked this on a EXT125 in the showroom of a local dealer and it was no better then mine. This also makes the addition of a heavy camera very difficult. I suggest you research this issue prior to making your final decision. There are several comments about this problem on this very web site. Maybe Mike has something more to say on this issue??? * Focus Knob: This knob is at the back of the scope. When the scope is pointing directly overhead the knob is next to the base making it difficult to turn to focus the scope. Also, with a high power eyepiece adjusting the focus, which is essential when a different eyepiece is inserted, often causes the object to move out of the field of focus. A good solution may be the Flexi-Focus from the folks at http://www.scopetronix.com. * Auto Star Arrow Keys: It seems that the arrow keys on the Autostar controller dont always seem to move the telescope. Sometime they just seem to be dead! I found the solution is to press one of the number keys which, in turn, select the telescope motor speed. Then the arrow keys work again. Mike any ideas on this?? * Spotting Scope Eyepiece: Because the spotting scope eyepiece is mounted just to the left of the telescopes eyepiece it gets in the way when using short, high power eyepieces and viewing with your right eye. Conclusion: Im glad I purchased this scope and I believe it is of good quality for the cost. With Autostar, it is easy to learn to use for the novice. Possible, with experience, some of the item I had trouble with will become easier. Still, considering the number of other people with similar complaints, It would be even better if Meade would redesign the vertical lock and focus knob! Good Luck! Larry & Kathi Somers Rancho Santa Margarita, CA.Mike here: Thanks for the comments. Your "Bad" items are typical. The locks are "friction" type and so suffer from what you are complaining about. Many users (including myself) have replaced the focus knob with a different device. The delay in the Autostar movement is "backlash"; you can remove it (but may or may not want to) so see the "backlash" and "percentages" articles on the Autostar Information page. Many people due add a second finderscope, sometimes a 1X or Red-Dot type finderscope; see the Accessory Reviews - Finderscopes page.
Subject: ETX 105?? Date: 1/6/04, 11:46 From: Nick Preece (firstname.lastname@example.org) Firstly, let me introduce myself. My name is Nick, I'm 29 years old and from Hereford in England, UK. I have little or no experience as an amateur astronomer and have never owned a telescope!! Hence the need for some advice from an expert. You've got a wicked website by the way!! Nice to see one that gives you the answers and information that you need rather than an endless stream of fancy pictures, animations and the usual rubbish associated with so called state of the art sites. Yours was very informative and I spent over three hours browsing it the first visit!! The picture galleries are amazing. I never realised amateur astronomers would have the resources to take such detailed pictures so far out into space!! Anyway, down to the nitty gritty!! I've always been very interested in the skies and planets etc. but never thought it would be financially possible to afford a decent telescope to do the job. My wife and I have just moved from our small city of Hereford to a little hamlet in the country. Our house is situated on a hill and we can see for miles all around, so as you can imagine, without street lights anywhere near us and the situation of the house the views of the sky on a clear night are awesome!! Jo (my wife), new I was toying with the idea of buying a telescope so she decided to buy me one for Christmas. However, the telescope she bought was a very budget affair which was very hard to stabilise and not much use for more than a quick glance at the moon. (nice of her to try though, eh!!). So, we have returned the said telescope and I have been searching the internet for advice on buying a decent one. Your site was the only one which gave me any help at all. The telescope I think I would like is a Meade ETX 105? The only thing that bothers me is that I feel it may be too advanced for me? What do you think? Reading some of your articles from other astronomers having problems with training the motors and setting magnetic poles (whatever that is!!), are these things really as hard to get your head round as they sound? As you can tell I have not a clue about astronomy so I really would be starting from scratch. What I really don't want to do is buy a telescope that I will be disappointed with in a few months time. I have been comparing prices of these ETX 105's and you lot across the water get a lot more for your money than we do!! An etx 105 over here costs around 700, that's almost $1300. Whereas I have found an ETX 125 in the USA for $899, that's just 500 in our yard. It's almost worth me travelling over and picking one up as well as having a holiday rather than paying our over inflated prices!! Unless you know of a cheaper way or dealer I can get one from? Anyway, I have bored you silly now so I will say goodbye. Congratulations once again on the website. Hope to speak to you soon Best wishes Nick Preece.Mike here: The ETX and Autostar are actually very easy to use. You do have to read the manual three times and then play with the system in the daytime to get the steps down. BUT seriously, just about anyone can do it. If you can take some time to learn the night sky (which people have done for many centuries) your enjoyment will increase but other than knowing where True North is located (or being able to identify Polaris, the "North Star", which will take you about 5 minutes with a star chart in your hand), no specific knowledge of astronomy, telescopes, or computers is required. Where many people get in trouble is that they make it harder than it is by not following all the right steps, in the right order, and then getting frustrated. That's not to say that aren't potentially problems: Meade's doc is not that clear in places (so reading the Alignment Tips on the Autostar Information page is helpful), batteries (low and/or cold temps) can cause create problems, and of course, there is the occasional "lemon" (which gets the most reports of course). The only other concern would be your "expectations" of what you will be able to see. You can't always use photographs to indicate the size, colors, and details of what you'll see with your eye; see the User Observations page for real reports.
Many thanks for taking the time to give me your thoughts. I will keep you posted on how I get on!! Bye for now Best wishes Nick.
Subject: ETX-105 RA Hard Stops Date: 1/5/04, 12:52 From: Don Sutherland (email@example.com) Niall Saunders was wondering if the ETX-105 had hard stops. I received my ETX-105 UHTC in June 2003. It does indeed have hard stops, just under 2 full turns apart. Like Niall, I was appalled at the arrangement of the wires to the Dec drive. The wires to my Dec drive were severed by the RA drive gears shortly after I received my scope. I plan to replace the original wires with a "clock-spring" made from ribbon cable. This is what the auto makers use to connect the switches and air bag mounted the steering wheel of a car. If anyone has built a clock-spring for the Dec drive cable, please e-mail details to Mike. In the interim, I put a cardboard disc between the coil of wire and the RA drive gears. The disc is about 3" in diameter with a small hole in the center and a slit running from the circumference to the center hole. The wires to the Dec drive are slipped through the slit to the hole in the center. This seems to keeps the wires out of the hungry jaws of the RA drive. Regards, Don Sutherland
Subject: ETX-105 (UHTC) RA question Date: 1/2/04, 15:31 From: Niall Saunders (firstname.lastname@example.org) I recently purchased an ETX-105 (with UHTC coatings, so assumed to be 'very new'). Having spent hundreds of hours looking through your site before 'taking the plunge' I felt that I would be fairly 'familiar' with the scope when it eventually arrived. Before even powering it up, I set out to establish it in an Alt-Az 'Home' position. However, there was NO INDICATION WHATSOEVER of ANY kind of mechanical end-stop on the RA/Azimuth axis. (There are no problems on the Dec/Alt axis). I have tried THREE full (manual) turns clockwise and anti-clockwise (very gently, and very carefully) and I do not come up against any end-stop at all. So, sitting in front of a BRAND-NEW (!!) $1000 scope, and armed with a dentist's pick and a pozi-drive screwdriver, I carefully opened the base of the unit, making sure that no wires were stretched, and nothing was compromised. Imagine my dismay to discover that the four wires, along with the black plastic shrink-wrap sheath, that lead up through the groove in the RA/Az fixing bolt were HORRENDOUSLY twisted. In fact they had been so badly twisted that the shrink-wrap sheath had split, and the insulation on the blue wire had parted. I carefully 'unwound' the twist - by turning the base unit in the appropriate direction until the strain had been relieved. Matters had been made worse by the fact that the four-wire 'cable' was wrapped round one of the base-mounting pillars (presumably originally for cable strain-relief). Further, just the fact that the shrink-wrap sheath had been fitted meant that the individual wires could not twist along the full length of the available cable - instead the twists had been concentrated at the exit point of the groove in the bolt. I have spoken to the dealer, mentioning the apparent lack of an end-stop, and he (fortunately) suggested that I 'take a look inside the base' just to see how bad things were (so, I don't feel that my warranty should have been affected - as the suggestion to do just that had come from my Dealer!). He certainly suggests that it goes back to Meade (UK), and I will be doing just that - but not until the long dark nights have passed, or until my next door neighbour takes delivery of his 8" LX90. But, the question I need answered is this: "Should there be a pair of mechanical end-stops on the latest chassis of the ETX-105 models, or has the need for end-stops been alleviated by the 'Cord Unwrap' facility present in my Autostar?" In any case, until such time as it fails completely, everything has been working fine. I just make sure that I do NOT manually move the RA/Az axis more than 180degrees, and I ALWAYS use the 'Park Scope' command at the end of a viewing session. This alone, albeit along with the fact that the v2.6 AutoStar software seems to 'know' how far it has rotated in RA/Az, has seemingly prevented any FURTHER damage to the Dec/Alt power and signal feeds. The only other question is "Why don't Meade just provide a pair of 'AUX' connectors - one on the DEC/Alt fork containing the motors, and one on the base unit. That way, an external 'curly-cable' could have been used on the whole ETX range, and the 'cable-through-the-bolt' problem could have been avoided completely. Easier to implement, and cheaper than a 4-pole slip-ring on the RA/Az axis. After all, those users with Electronic Focusers already have a cable-wrap problem to contend with, and their curly-cable solution seems to work fine. (Come on Meade, get with the program, and start listening to customer feedback!!). Thanks in advance. Regards, Niall Saunders Aberdeen, ScotlandMike here: I haven't heard that the ETX-105 no longer has hard stops but it is certainly possible that Meade has changed the design of the base to be like the ETX-60 and ETX-70. Is the control panel on the base or a fork arm? In any case you could enable "Cord Wrap" on the Utilities menu to help avoid wrapping.
The control panel is still on the base - to all intents and purposes no difference between 'standard' ETX models, familiar to all of us. Yes, I have enabled 'Cord Wrap', and this seems to now be the ONLY level of protection that I have. I appreciate that you, personally do not have the ETX-105, but I am hoping that other (Clay Sherrod included) may have a definitive answer on this one (if indeed you do not have a friendly Meade engineer to whom you can pose the question). It is also interesting to note that there does not appear to be any form of 'serial number' identification on the telescope assembly itself (other than an 'inspected by' number on the OTA). How on earth do Meade establish whether a particular telescope is actually worthy of warranty repair? I will pass on my experience with Meade (UK), from here in Scotland, so that others might benefit. Thanks for taking the time to reply (as the leading contributor to a GPS users Forum on the internet, I know how time consuming it can be, dealing with upwards of a hundred emails a day!!). Regards, Niall
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