ETX, GENERAL FEEDBACK
Last updated: 31 July 2013
This page is for comments and user feedback about ETX telescopes. ETX models discussed on this page include the ETX-60/70/80/90/105/125 (EC, AT, BB, Premier Edition). This page also includes comments and feedback of a general nature. Comments on accessories and feedback items appropriate to the ETX-90RA, DSX, and DS models are posted on other pages. If you have any comments, suggestions, questions or answers to questions posed here, e-mail them to me for posting. Please use an appropriate Subject Line on your message per the Site Email Etiquette. Thanks. Remember, tips described on this site may invalidate the warranty on your telescope or accessories. Neither the submitter nor myself are responsible for any damage caused by using any contributed tips.
Subject: Meade 35-4702-00 electronic controller wiring diagram Sent: Tuesday, July 30, 2013 06:01:44 From: Alex Card (email@example.com) I wonder if any kind soul can help me. I'm a total noob where telescopes are concerned but recently bought an ETX90 which has a dead Electronic Controller model number 35-4702-00. There is no activity from it so I unscrewed the back and found that 7 of the 8 wires were detached from the PCB. The Orange wire is still connected to the 2nd point from the left but I'm wondering if anyone can advise me which points the other colours should be soldered to please ? Many thanks, Alex Card
Subject: Eyepiece holder Sent: Tuesday, July 23, 2013 17:06:05 From: Gregory J. Scotti (firstname.lastname@example.org) I wonder if you might know the thread size and length of the eyepiece holder on an ETX 80? I lent my telescope to a friend, and got it back minus the eyepiece holder. Unfortunately I didn't check the scope right away and Meade tells me this piece is part of the telescope and NOT available as a separate part. My friend has offered to pay for the holder, but it looks like I'll have to have it made. Any help you can provide would be greatly appreciated. Gregory Scotti Sent from my iPhoneMike here: If you mean the screw, see "Q. What is the size of the eyepiece holder screw?" on the ETX FAQ page.
Actually, the entire eyepiece holder tube that screws into the telescope is what I'm missing. It's the tube that the eyepiece drops into. I was hoping maybe someone would have the dimensions of this tube so I could have one made, as Meade doesn't offer this for sale and weren't very helpful about giving me the dimensions. Again thanks, Greg ScottiMike here: Egads. I don't know the dimensions of the ETX-80 holder but you might try Telescope Warehouse (link on the Astronomy Links page) for a replacement.
Subject: Re: Wide angle 30mm+ eyepiece Sent: Monday, July 22, 2013 07:25:16 From: Chris Mcilhargey (email@example.com) Ok thanks a lot! So in your opinion would a 32mm be too much? Sent from my iPhoneMike here: I have found my 40mm useful when wanting wide-field, low magnification views. A 32mm eyepiece can be useful; just understand its limitations.
Ok thanks I am after a nice wide view. I think I will try find a Meade 4000 32mm giving around 60x mag. Thank you very much for all your help btw! I really do appreciate it! I got the etx flashed to 43eg and connected and controlled thru stellarium on my MacBook. I just bought a modded web cam so I can see what I'm looking at on the laptop too! Very excited :) Cheers Chris
Subject: Wide angle 30mm+ eyepiece Sent: Sunday, July 21, 2013 04:23:05 From: Chris Mcilhargey (firstname.lastname@example.org) I'm sorry to bother you again but I was wondering if you could maybe give me some advice. I really want a wide angle 30mm or more eyepiece. Due to the etx 125 long focal length even my 26mm is still quite high magnification. I had a look in the eyepiece section here on your site but most are very old. Was just wondering if you could suggest a good one? I'm not looking to spend a fortune! Max maybe like 70 ($100). Thanks Chris Sent from my iPhoneMIke here: I've used a 40mm eyepiece on my ETX telescopes. I also use a wide-field adapter on my ETX telescopes. There is one issue with either: the central obstruction becomes more evident. Long focal length eyepieces will allow you to see the central obstruction. Depending on the particulars of the eyepiece, it can be more or less evident.
Subject: mended Sent: Thursday, July 18, 2013 13:17:38 From: GPLeask@aol.com (GPLeask@aol.com) Just had the guy that I work with around, to have a look at the scope. He turned the lower part of the up/down mechanism around 90 degrees, so the worn teeth were at the back, put it all back together, problem solved. It still makes the odd click, but it's almost back to as new. Just had it tracking Arcturus, even though it's light and cloudy, but Stellarium never lies. It's a shame there isn't a cut off point when things get too low or too high. Thought I'd tell you my good news. All the best, George
Subject: Etx 125 turning left is very loud Sent: Thursday, July 18, 2013 08:07:08 From: Chris Mcilhargey (email@example.com) First off can I just say your site is amazing!! Thanks so much for it! I have spent many hours reading all I can about the etx here :) Sorry if its mentioned somewhere however I couldn't seem to find the info I'm looking for (prob cause I have no idea about the terminology used for the mounts and gears etc) basically my new (used) etx125 makes a considerably louder noise when moving left! All other directions seem fine! Only left is very loud. Is there anything I can do that is basic enough for me to do without damaging stuff to try and fix it? Or any explanation on why it does this? Much appreciated! ChrisMike here: There are a couple of possibilities but before getting into those, be certain you have done a CALIBRATE MOTOR and TRAIN DRIVES (on both axes). If that doesn't solve it, the gear motor mount could be loose (or broken). With the azimuth (RA) axis unlocked, do you hear the same loud noise when slewing left? Does the slew speed matter? With the axis unlocked, if you slowly move the telescope to the left by hand, do you feel any resistance difference vs turning it to the right? If so, there could be some obstruction.
Wow that was a fast response!! :) I can confirm that I have done both of them. Thanks to your site for explaining how to do it :) How often do I need to train the drives? Every time I use the scope? I'm sure I read it's only every few months or something. I will try and see if there feels like any interference when moving manually tonight after work. However I'm pretty sure there isn't. From memory the slew speed does decrease the noise however all directions are quieter and going left is still louder than another direction. It's not a big deal to be honest as it still moves and from what I can tell it tracks fine. I just thought it sounded a bit dodgy. And wanted the opinion of the etx god!! :) Thanks again! I will update you when I have checked your suggestions. Cheers Chris Sent from my iPhoneMike here: TRAIN DRIVES usually doesn't need to be done very often. CALIBRATE MOTOR should be done when replacing the ETX batteries or switching power sources. It should also be done if battery power is getting low and no replacement batteries are available. TRAIN DRIVES should be done after doing an AutoStar ROM update (but version 4.3Eg is the latest, best version for the older AutoStar #497). It should also be done following a RESET. Otherwise, do it if you see "rubberbanding" or other GOTO/tracking oddities.
Ok thanks very much! I have got into a habit of doing a calibrate motors each time I use the scope as it only takes seconds. I always use the 12v into a plug socket so nothing to do with batteries. Ohh on that point about autostar update. It's an old version off the top of my head 39 something. I have ordered what I hope is a working USB to serial adapter to update it (first one I bought was junk) It's unlikely but would the old version of autostar have anything to do with the loud noise nah? Btw totally off topic but... I love this scope! It's truly amazing. Thanks to your site it gave me the confidence I needed to part with my money! (Third scope in 6 months of this hobby) i managed to push the magnification up to 475x on the moon the other night and it focused fine!! :) Also got my first view of a DSO M13 and almost shat myself when I found it!! :)Mike here: Yes, the ETX is a "mighty" telescope! The older version is not likely to be the culprit. As to the USB adapter, not all work reliably with the AutoStar. If you find that the AutoStar Update application from Meade doesn't stay connected, try StarPatch from StarGPS (www.stargps.ca) or AutoStarX if you use a Mac (http://www.rti-zone.org/macosx_autostarx.php).
Thanks for that! i will use the link for updating with a Mac. i did hear tho that autostar suite cant be used on a mac :( Ok so i tried to see if there was any difference when moving manually. I couldnt notice anything. it moved left and right with no problems. Do you think it would be worth opening and having a look inside? i dont want to break anything.Mike here: Opening up and looking is probably a good idea.
sorry for bothering you mate! I have one question about the autostar update. i downloaded autostarx to update using my macbook. i then cleared eeprom. But i dont have the latest version of autostar. Where can i download it? i tried the meade site but it only gives .exe for windows files. Sorry if this is a stupid question :) Cheers ChrisMike here: See the AutoStar Software Archive on the Helpful Information: AutoStar Info page. You want the ROM file 4.3Eg.
Love the speed of your responses btw!! Thanks for that. Another stupid question... Do I pick the latest one yeh? I.e. "landmark path kit for autostar v43eg (v30)" or is that just a addon to "patch kit for v43eg" dated 2007? CheersMike here: Start with no patches. The patch software is Windows only. And just to clarify, use the 4.3Eg ROM file from the AutoStar Software Archive page.
Ahhh ok I found it now! Thanks so much! I should have followed your instructions better the first time! It's flashing 43eg now :) Btw just in case it may help someone not make the mistake i did when attempting to connect the etx to a mac...and buy a cheap USB adapter. The second one I bought seems amazing with both windows 8 and osx 10.2.8 just download driver and plug it in. no messing about with com ports or nothing. For only 10. Gets great reviews too. http://www.amazon.co.uk/gp/aw/d/B00425S1H8/ref=mp_s_a_1_1?qid=1374260396&sr=8-1&pi=SL75 Thanks again for the help!! Now I will attempt to open this beast and try and work out what's making this noise in the mount :)
Subject: Re: ETX 90 Tracking Problems Sent: Wednesday, July 17, 2013 07:42:32 From: Micki Goodman (firstname.lastname@example.org) Thanks for your typically quick reply. I should have told you I do not have Autostar. It is the simpler, multi-button ETX 90EC hand controller. I hope you, or anyone else has seen this problem before, and found a solution. Thanks again.Mike here: You previously said "If I try to adjust the tracking speed for the left side of the FOV then the tracking is off on the opposite side (opposite drift)." How are you adjusting the tracking speed?
The hand controller has tracking speed adjustments, via the focus in/out arrow buttons, when you enter the appropriate "Mode". It allows incremental speed changes for slower and faster. I typically try to get the best tracking in the middle of the FOV, but it is more accurate, initially, to the right side of the FOV. I have had little or no problems setting the Polar alignment, thanks to your previous info. Once I get this tracking issue solved, I will be able to do longer video clips. Thanks again for all your help.Mike here: It has been years since I've used the EC Handcontroller. I thought the only speed adjustments were slewing. There are four slewing speeds available with the EC Handcontroller.
All true, Mike, of slewing. So-what do you recommend (who might know) as to the tracking issue? Thanks again.Mike here: If tracking is inconsistent, the RA gear could be loose on its shaft. Or the motor is going bad. You could contact Dr Clay Sherrod for his Supercharge tune-up service. Or get an AutoStar #497, which provides tracking speed adjustments.
Thanks for the suggestions. I will check the RA gear first, then decide from there which steps to take. As I mentioned, the hand controller I have has tracking speed adjustments and they work quite well. I look forward to more of your Cassiopeia postings, when your wether clears.Mike here: You are correct. I checked an ETX EC manual and Appendix A described the key presses to change tracking from 0.5% of sidereal rate to 65%, either faster or slower. Getting to 65% requires 127 key presses. I had forgotten about this adjustment capability. Of course, this only applies with the telescope mounted in Polar mode, either with the short tripod legs (optional with the ETX-90EC) or on a tripod that can be adjusted for your latitude. If you still see some drifting after making the adjustments, it could be that the your mount is not precisely polar aligned. Using Magnetic North may not be accurate enough if your local Magnetic Variation is large. But sighting on Polaris should be accurate enough for short durations. For more accurate polar aligning, use the "Drift Method" (see the "Polar Alignment Guides" section on the Helpful Information: Guides & References page.
I spent some time today and tonight checking focus shift and later tracking issues. During the day I took off the electric focuser and there was negligible focus shit, manually. I lubricated the electric focuser brass gear and the circular brass gear, that came with the electric focuser mounted on the focus shaft), and it made the shift more tolerable. The tracking problem persists and I will look at the RA gears soon (I did a complete overhaul, lube etc. not too long ago). It was too gusty for photography and even viewing was turbulent, but the observing was still enjoyable of the Moon and Saturn. As a side note, I made some stands, to attach tarps to, to help block neighborhood light pollution, and from passing cars lights. It will be helpful, when the wind is not so strong. The last post you had of your neighbors' lights, to your north, seemed more considerate. I hope that continues, when the weather affords more sessions. Yours-Fred (you may sometimes see my wife's name instead of mine since we only have one joint email account).
Subject: screws? Sent: Tuesday, July 16, 2013 10:40:03 From: GPLeask@aol.com (GPLeask@aol.com) The screws on the Meade are a different kind, as you know. Any chance of you telling me what does fit the screws? The guy I work with is a whizz with electrical stuff, and is pretty good with his hands. I'm going to get him to come have a look at it, and would like to know what kind of screw driver to take with him. It might, hopefully, be an easy fix, even though I doubt it myself. I'm hoping it's just something jumped out of line. Regards, GeorgeMike here: Many screw heads are "hexagonal cross-section" and need a "hex key" (also known as an "Allen wrench"). They may be SAE or Metric sizes.
Subject: Spares? Sent: Tuesday, July 16, 2013 07:55:34 From: GPLeask@aol.com (GPLeask@aol.com) Do you happen to know where I could find a vertical cog for my ETX? I was trying out the goto the other night, went to answer the phone. The next I knew it was ripping the cog apart. Having looked all over the net, and with Meade saying they don't do the ETX any more, I'm stumped where to find a new or second hand cog. Would the cog out of my ETX 80 fit the 125AT? Thanks in advance, GeorgeMike here: I suggest trying Telescope Warehouse (link on the Astronomy Links page). Also, there are some gear source and replacement articles on the Helpful Information: Telescope Tech Tips page. As to the ETX-80, doubtful.
Subject: ETX90EC skewing problem Sent: Monday, July 15, 2013 08:56:04 From: Tom S (email@example.com) Using the controller, skewing at low speed is perfect in all four directions. Motor operation and gear box sounds are normal. However in the next three higher speeds the motor seems to bog down (like not getting the correct voltage) and the gear train will not rotate. Removed the bottom cover for a visual inspection of wiring and components and all looks very satisfactory. Suspect a faulty PCB. Is there another item I should be concerned with? and am I on the right track? Thanks, TomMike here: I assume from your description that you have only the standard EC handcontroller and not the AutoStar. Could you be overtightening the axis locks. Is the slewing (not "skewing") problem only on one axis or both?
Thanks for your fast reply. Yes on the standard EC handcontroller and not autostar. Tried different tension on the axis locks, no help. No slewing on either axis. I never use higher speeds at all, maybe I need to be satisfied with what I have (the one low speed) but wanted to have the scope perfect. TomMike here: Have you replaced the ETX batteries with fresh ones? Be certain they are all inserted correctly.
Batteries new, also used a power supply to make sure....no higher speeds. TomMike here: With both axes unlocked, can you hear both motors running at the higher speeds? Also, what's the voltage and amperage supplied by the external power supply?
Subject: clean gear plastic ETX 70 Sent: Monday, July 15, 2013 01:09:49 From: toni toni (firstname.lastname@example.org) Hello, my name is Antonio. I have a Meade ETX-70. I'll clean plastic gears has the mount. My question is: I read that lithium grease is not suitable to be plastic gears. What type of grease is recommended?. Thank you very much for your attencion.Mike here: See the current Live Forum feedback; I provided an answer on grease last night.
Subject: re: ETX90 Motor Drive Sent: Saturday, July 13, 2013 19:33:28 From: richard seymour (email@example.com) Assuming you mean an ETX90 with Autostar, fascinating (to some of us) detail can be gleaned from Meade's patents. I normally use http://www.pat2pdf.org/ and give it these numbers: 6,304,376 6,392,799 6,445,498 6,563,636 align: 6,922,283 there's also 7339731, 7221527, 7092156, 7079317, 7053992, 7414707, 7227223 In short, the motors are all DC analog motors with 150 Hz PWM drive pulses. There's a local processor on each motor card which does the "tight servo" loop processing to keep the motor moving at a speed commanded by the master CPU in the Autostar. have fun --dick
Subject: ETX90 Motor Drive Sent: Tuesday, July 9, 2013 14:21:58 From: JimD (firstname.lastname@example.org) Just recived the Meade ETX90 scope, & am in the process of checking it out. Do to the less then average sky conditions, & bumper crop of bugs, astronomical views have been pretty poor. However the terrestial views, are equal to the 3.5" Questar, which I have used on & off over the past 4 decades. Star tracking, has been good, considering I have it on a wooden deck in the back yard, & have not done a true polar alignment. Having been involved with the design of optical instruments, I was wondering if you have any informatioin as to the drive systems of the ETX, for my own curiosity? i.e. prints or equivalent that show the detail drive operation. The ones I have been most familiar have a dual servo & sync. A.C. motor (RA only). Thank you, JimD.Mike here: You didn't specify whether you have the ETX-90RA (original ETX without the handcontroller), ETX-90EC/AT (with EC or AutoStar handcontroller), or an ETX-90PE (AutoStar; LNT). But all the information that I have is available on the Helpful Information: Telescope Tech Tips page and the Helpful Information: AutoStar Info page.
Subject: Re: Dusting off old scope, Stuck "finding level" Sent: Tuesday, July 9, 2013 08:41:36 From: email@example.com (firstname.lastname@example.org) When I get back from Yosemite I'll take on the project of building a cable and doing the update to see if that resolves these issues. If not, I'll reach out to Dr. Sherrod. Thank you again for all your efforts.
From: Ron (email@example.com) I had some problems with my LNT module and found I had a broken wire in the harness/wires that runs from the LNT connector to the DEC Motor card in the right fork. If one of the wires that is in the AUX circuit is broken causing intermittent operations Eric may get the Red Dot but still not be able to get the full auto alignment. Just guessing her but as the ETX rotates a broken wire may break the circuit causing everything to stop. I forget what my symptoms were but at the time I was able to buy a LNT module from Meade before I discovered the broken wire. The ETX OTA and forks pretty much has to be disassembled to be able to test the wires for continuity. Plugs are on both ends. I will try to find the file with the part numbers for the connector and pins and forward it. They are MOLEX parts and available from several sources. Only the pins would be needed. Ron
Attached are the MOLEX Documents for the connector housings and pins, male and female. Plug Housing 1 Plug Housing 2 Plug Housing 3 Plug Terminals One thing to note is that there are different part numbers for single pins and tapes of pins. Ron
Subject: about your FaceBook Sent: Tuesday, July 9, 2013 00:47:47 From: T.Yashiro (firstname.lastname@example.org) You taught many about ETX to me. I am very thankful to you. If I can,I would like to visit your FaceBook. I found your twitter. But I could not find your FaceBook. Please tell me where your FaceBook is. I am glad if I can be your friend by FaceBook. Regards, Takashi YashiroMike here: I am not on Facebook. There are too many security issues with Facebook.
Subject: Help please, with RA problem Sent: Monday, July 8, 2013 15:27:25 From: MICHAEL ROLLO (email@example.com) Just purchased a ETX 105, of course i did all the things one shouldn't do when purchasing from a stranger. I didn't check to see if it was functional. Well, Fortunately , Cosmetically it is near perfect, and I did pay 350.00 for it, which . I think is pretty good. Only one problem. The RA doesn't work it just makes noise. I tried a setup first, and once it started, Dec worked fine, but when it should have shifted left or right, it just didn't move, there was noise, but no movement. I can't get any help from Meade support of course, and I can't afford the cost from the few people that fix this sort of thing. Most fixes would probably cost more than what I paid for it. An hour later, frustrated, I went back to the scope, and by tilting the scope to the left while it was still on the tripod, the RA did work , but only while I held the arrow key down, once I stopped, it would not work again, unless I tilted it again. It also would only move counter clockwise. Clock wise only produced noise. Like fast clunking? I've tried all speeds, and all produce the same effect, nothing but noise, I do not want to hurt the scope so I wont use it till I fix it...but how ??? Does anyone know a fix for this, and does it sound serious? Thank you for taking the time to read this. Regards, Michael RolloMike here: With the axis UNLOCKED, do you hear the same noise? When locking the axis for normal operation, be certain to not over tighten it. It should be just tight enough that the telescope will not easily move if you push it by hand. If the lock lever seems to not tighten enough, there is an easy fix for that. Also, assuming no other problems, be certain you have done a CALIBRATE MOTOR and TRAIN DRIVES (on both axes).
Thank you, It sounds the same locked or unlocked. There is no problem with the locking mechanism, it wont reach midway befor it it gets hard to push any further..which,..I'm afraid I did..once. I have noticed at slow slewing speeds that even when it wont actually move to the left, I can see it in the eyepiece that it is trying to grab at something. The sound is like a power drill. and when I try to slew to the right...it will make a clunking sound. I am thinking of opening it up. I have been assured by the previous owner that it hasn't been used more than a half dozen times..i tend to believe her. As it looks untouched. Last it was touched was 6 years ago..so she says. I can't imagine what could make this happen. Thanks again, if you can think of anything else that it may be, please feel free to let me in on it..it is greatly appreciated.Mike here: Since the sound is the same when unlocked, it could be that a motor or gear has become loose. You will have to open the base and look around. You may see a loose motor or gear mount or perhaps even a broken mount. There are some repair tips for that on the Helpful Information: Telescope Tech Tips page.
Subject: Dusting off old scope, Stuck "finding level" Sent: Sunday, July 7, 2013 23:16:48 From: Eric Rosenzweig (firstname.lastname@example.org) I have an ETX-105PE running version 43Ea that hasn't been used in a couple of years and I've decided to get it going again. It worked when I put it away a couple of years ago (scope wrapped in original plastic bag and placed in locking case). So, I replaced the ENT battery as the old one was dead and have been trying to get it to work ever since (checked the new battery and voltage is fine). Here's what I've done and the results: 1. Started by trying an auto align and it gets stuck at "finding level". Can sit there for over 15 minutes before I give up and turn it off/on or the Autostar just goes black. 2. Tried a two star align using Deneb as the first star. Scope pointed 180 degrees from Deneb 3. When I try an auto align it comes up and prompts for time. The date is correct, but the time is always 8pm. I found an email on your site referring to make sure the red-dot finder works and it does. 4. Tried calibrate sensors. Gets past "finding level" slews "finding North" (actually end up pointing West) and gets stuck at "releveling". Let it stay for 15 minutes before reboot. a. Tried it again and it never got past "finding level" 5. Did a "Reset", went through setup process and all of the above still happening. Oddly after the reset it was as if it didn't see the LNT as I didn't get the usual prompts for auto align. However, after I turned it off and back on, it appeared normal although still wouldn't get past 'finding level'. I've searched your site and the internet and haven't found anything along these lines other than checking the connection between the LNT and the scope which I did and it's fine. I'm heading to Yosemite next week and was hoping to get this scope going. Obviously I can use the scope without these features, but was hoping for more. Any help you can provide would be greatly appreciated. Thanks, EricMike here: First, the AutoStar will always show 8pm (or 2000) as the default time on power on. Second, you might want to update to 4.3Eg (the last, best, version for the old #497 AutoStar). If replacing the battery in the LNT didn't help (still locking up finding level), then it could be that the LNT has failed. If that's the case, you should still be able to use the non-Auto alignment modes. So, lets start by getting that to work. You said (#2) that Two Star Align was not working properly. Have you done a CALIBRATE MOTOR (different than CALIBRATE SENSOR) and a TRAIN DRIVES afer you did the RESET? If not, do those. Also be certain you have fresh batteries in the ETX (and not just the LNT). Next, remember (in case you forgot after a couple of years on non-use) that the HOME position for Auto and non-Auto alignment modes are different. Be certain to use the correct one.
Thanks for getting back to me so quickly. Couple of questions before this evening: 1. I can't find an option for CALIBRATE SENSOR. I had found that note on your site, but can't find that option. Even in the manual for scope where it shows all the Autostar menu options there's not one for CALIBRATE SENSOR. Is this hidden somewhere? 2. I thought I had read on your site that if the LNT was working correctly it would keep the time, but if that's not the case that's fine. FYI, I did notice that there were a couple of times where I checked the time and it was about 30 minutes fast. Thank you again.Mike here: If there is no CALIBRATE SENSOR option, then the AutoStar is not "seeing" the LNT module. The LNT will get the time IF you have the optional Atomic Clock module connected.
I'll play with it more tonight but I thought if I could turn on the red dot finder, which I can, the LNT was talking to the scope? One other thing that happened once, which may confirm the lack of connectivity, is that after the reset when I went to CALIBRATE MOTOR the scope slewed a bit up and over while saying TESTING MOTOR. after I turned it off and on that didn't happen. I just got stuck on FINDING LEVEL. Other than the physical connector from the LNT is there anything else I can check? Thanks again.Mike here: Does the Finder options appear in the MODE menu display? If not, then there is some problem with connectivity. But that could be a separate issue from the leveling sensor problem. As to CALIBRATE MOTOR, yes, it briefly runs the motors to check operation and measure the power output of the batteries via the optical encoders.
Well, I'm at wits end. I forgot that I had a new LNT from when I first got my scope and the red dot didn't work right so OPT got me a new one on warranty and then was able to get the other one working. Long story short I have two. So I've done the following with the following results: 1. Put new battery in new LNT (call it nLNT). Got calibrate sensors as an option, kicked it off and it worked great. Leveled, rotated to find North and then got stuck at releveling. Joy followed by despair. 2. Put in old LNT (call it oLNT). Got calibrate sensors as an option as well. Definitely wasn't there before. Tried it and it got stuck at leveling. 3. Put in nLNT. Tried to calibrate sensors, got stuck at leveling. 4. With both oLNT and nLNT calibrate motors works fine. 5. With oLNT tried 2 star alignment (thanks for the reminder that the home position is different) and it got in the ballpark, but not really close. When I finished with two stars it told me alignment failed. a. I couldn't remember how to set time with DST so I tried it with DST off, and when it was 9:30 local time I set it to 9:30 with DST ON and 8:30 with DST ON thinking that might help, but didn't get me much closer to the alignment stars. For the record if it's 9:30pm here in California where we're in DST, how should I set the clock? 6. Had the same oddity with the time slipping 30 minutes forward with oLNT. 7. Also on more than one occasion after turning off/on when it came to date the month field was wacky. As I scrolled through I got gibberish, REV and then finally the months. I've repeated this a couple of times and never get past leveling. With both LNTs I get the red dot finder options and they seem to work fine. I don't have an RS232 port on my computer so I would need to get a USB to RS232 cable to update the Autostar, but I don't have time for that before I leave. So, I'm at an impasse and it would appear there's a serious problem somewhere so, given that the scope is certainly out of warranty, is there anyplace better to send it for a tuneup other than Meade? Thanks again for all your help and your responsiveness. Much appreciated.Mike here: First on DST: when your location is using Daylight Saving Time (as California is now), DST should be set ON. When you "fall back" later this year, set it OFF. For locations that don't do the clock dance (like here in Arizona), DST should always be OFF. I'm beginning to think the AutoStar is at fault since both LNT modules experience the same problem. As a next step, I suggest updating it to 4.3Eg. Use either the Meade AutoStar Update application version 4.6 (both the ROM file and application are available on the AutoStar Software Archive (on the Helpful Information: AutoStar Info page). You can also use StarPatch (from stargps.ca). You will need a #505 serial cable (easily made; see the AutoStar Info page). If your computer has only USB, you will need a USB-serial adapter. Not all adapters work reliably with the AutoStar; I recommend Keyspan adapters. If you have another adapter, use StarPatch as it is more forgiving of USB-serial adapter issues. If you do want to send it to someone for repair, I suggest contacting Dr. Clay Sherrod for his Supercharge Tune-up Service (see the link on the ETX Site home page).
Subject: ETX-125 DEC Slip Sent: Sunday, July 7, 2013 13:13:24 From: John Deriso (email@example.com) After a total overhaul of the mount (bearing changes, motor swaps, etc.) then RESET/CAL/TRAIN, my go-to's are fine in any AZ or DEC direction, but then I get a slow downward drift of the OTA. No AZ drift. Is there anything else but DEC clutch slip that can cause this in astronomical target mode? I haven't fooled with DEC ratio or percentage. Didn't try terrestrial mode yet to confirm it's not tracking error. Trying to avoid tearing completely back down to reach the DEC clutch surfacesthe one thing I didn't inspect. I'm quite familiar with ETX 70/90/125 repair and the torque normally needed for DEC lock. JohnMike here: Just to confirm, did you TRAIN DRIVES on both axes? If so, it could be slippage. Is the drift downward the same regardless of OTA orientation? That is, is it the same if pointed southward as when pointed eastward? Is it the same if mounted Alt/AZ vs Polar?
Yes, trained both drives, still downward drift after go-to in any direction. No AZ drift. I never mount polar. I'm guessing that checking for DEC drift in terrestrial mode (motors not running) will confirm it's not tracking error, but clutch slippage. I was curious if DEC drift like this could be firmware related or if it really is likely mechanical slippage. Shame on me for not inspecting the DEC clutch for grease or wear when I installed this replacement base/forks onto an existing OTA. Considerable cannibalization to get one ETX-125 from 2 hulks, but I didn't strip down the DEC arm. Didn't try switching Autostars either. JohnMike here: Certainly an error in the AutoStar (or encoders) or an error in DEC training data recording could create a downward drift. Another possibility is an error in where the AutoStar thinks it is. Check the site location.
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