Last updated: 31 March 2008
This page is for user comments and information specific to the Meade ETX-60AT, ETX-70AT, ETX-80AT-TC, and ETX-80BB. Additional information is available on the ETX-60AT & ETX-70AT Announcements page. Comments on accessories and feedback items appropriate to other ETX models are posted on other pages. If you have any comments, suggestions, questions or answers to questions posed here, e-mail them to me and I'll post them. Please use an appropriate Subject Line on your message. Thanks.
Subject: Broken Elevation counter spring mount Sent: Sunday, March 30, 2008 17:33:47 From: Willard561@aol.com (Willard561@aol.com) I have a ETX-80 that I bought it at Goodwill for $30.00. As you would expect it has a "few issues", the most obvious was the mirror was loose, and it was an easy fix. It also has a clunking sound from the right hand fork. When I got it apart thanks to the info on your website, I found the clunk was the attachment for the counter balance spring to the elevation axis. I've attached a picture of it, as it's made from Acetal, I doubt any type of glue could be used to fix it. Can you think of any repair ideas other than send it back to Meade? Thanks for your work. Bill Higdon
I guess a good question is the spring really needed?Mike here: I would assume it is there for a reason.
Subject: Re: ETX 60 AT want focuse Sent: Tuesday, March 25, 2008 18:19:26 From: Charles Powell (firstname.lastname@example.org) Thanks for your help Mike. It took quite a few turns to bring it into focus. I watched the eyepice for movement and was not watching the objective lens housing for movement. I then tried to put the telescope back into it's case and it would not fit. The tube waas to long so I had to run the focuse out to move the lens housing in. Thanks again for your help. Now if you could clear out the clouds that would be great. CharlesMike here: If anyone has any "tech tips" about getting rid of clouds I'd be happy to post them on the Tech Tips page!
Subject: ETX-60AT used as a Balloon Theodolite Sent: Tuesday, March 25, 2008 17:53:18 From: Jim Rogina (email@example.com) I'm working on the following alternatives and combinations: I installed the ASCOM "platform" driver for Autostar however the appropriate 'Meade LX200 Classic Driver v5.0.1' available from ascom-standards.org clearly specifies the #495 and/or #497 controller. My EXT-70AT's Autostar 494's firmware is at Version 10E1; I plan to purchase and install a #497 controller as soon as possible... as I understand it, I just plug-in the new #497 controller to upgrade? Richard mentioned that POTH and PIPE may come with the current ASCOM driver, and so it makes sense to upgrade the Autostar and install the current version of the driver. Unfortunately Outlook blocks .vbs files on my PC, apologetically, hopefully; Richard might resend his script; maybe a different file extension will fool my Outlook configuration. In the mean time, I'll order the #497... That is if there are no further Autostar upgrade complications to consider. Alternatively, Richard says Andrew's MyScope can track where an ETX is pointing with user-program-supplied timestamps... Apparently you can specify serial commands to output at a specific time/rate, and it will log the results. I see on your website the following link: http://members.optusnet.com.au/johansea/ I'll download and play with this program tomorrow. For future balloon theodolite units (total cost < $400.) I'm considering the ETX-60ATBB, upgraded to Autostar #497 and using a 40mm Wide Angle T Threaded Eyepiece with a directly attached ToUcam - [Philips PRO II PCVC840K Webcam]. http://www.telescopes-astronomy.com.au/telescopes095.htm Telescopes-Astronomy.com produces the 1.25" (32mm) diameter eyepiece which has a focal length of 40mm and a T Thread on the end for directly connecting the ToUcam. The clear aperture 26mm lens is flat and positioned close to the end of the eyepiece to keep it as close to the camera as possible, widening the field of view. The magnification is 350mm/40mm = 8.75X or 17.5X (with the flip-Barlow lens); very much like a "real" theodolite. This configuration should allow pibal following on a laptop screen with a wider, more desirable Field Of View. The internal flip-Barlow lens will provide magnification doubling when called for... hopefully someday, auto-tracking with PHD Guider will be possible. http://www.stark-labs.com/phdguiding.html Maybe I should send the DSI back to Amazon; it's supposed to arrive Thursday... Thanks so much for everything Jim RoginaMike here: Yes, just disconnect the #494 and connect the #497. Be certain to select the telescope model and mounting mode and do a CALIBRATE MOTOR and TRAIN DRIVES.
Will I need any additional cables like the 505 or possibly the USB/505 to connect my computer to the #497?Mike here: You will need a #505 serial cable, which is easy to make using information on the Helpful Information: AutoStar Info page on my ETX Site. If your computer does not have a real RS-232 serial port and only USB, you will need a USB-serial adapter. Note that not all work reliably with the AutoStar; see the article "AutoStar and USB" on the AutoStar Info page for more details. I use a Keyspan adapter with my Macs and it works fine with the AutoStar.
Here's another well-reviewed free telescope command/control program, RTGUI http://www.debunker.com/astro/rtguipage.html and the final line on the features list says: "# Command-Line Parameters allow Scripting for automated operation" Chasing down that link led to the information of where/how they talk to the scope: "1. RTGUI+S is a 32-bit program for Windows systems such as Win 95/98, ME, XP, NT 4, Windows 2000, etc.. It is written using Microsoft Visual Basic 6. The Application Program Interface used to access the COM port is taken from "modCOMM" published on TheScarms by David M. Hitchner (see http://www.thescarms.com/VBasic/CommIO.asp). " and "RTGUI+S is based upon an earlier MS-DOS program, "RTASTRO" (RT.EXE). RTASTRO is still available for Windows 3.1 and DOS users at http://www.debunker.com/astro/rt_702.zip. It has many of the features of RTGUI+S, but without the easy-to-use interface. The accuracy of its planetary and lunar positions is not nearly as good as RTGUI+S. It is no longer being supported." ... that latter program (or the modCOM package) may perhaps be easily warped into doing precisely what you want (we can hope). Whoops! Maybe not: "3. RTGUI+S does not read status from any telescope during GOTO operations. It only writes the current object's RA and DEC to the control port, using the data format proper for that scope's protocol. But this is good - there have been situations when this code, because of its total simplicity, has worked and certain expensive, heavily-advertised astronomy programs would not! " But THEN they say: (note the 494 information!) --- 5. Known Problems: Changes made to code to read location from Meade scope, attempting to address a problem reported with the new RCX400 scopes (apparently a small change in scopes' responses). Issue not yet resolved. Problems have been reported with the Goto on the Meade Autostar model 494, which has more limited real-time capabilities than the other Autostar models. A 5 ms delay has been inserted between each character to attempt to remedy this problem. In addition, there is a 50 ms delay between the commands. However, the problem is not yet resolved. --------- have fun --dick
In fact, even -Meade- provided an example program that would (mostly) work with the 494... they did it in the Appendix of the Classic LX200 manual. Visit www.meade.com/manuals and download the LX200_Classic_Manual.pdf Buzz down to page 58, and there starts the source listing of a Basic program for talking to an LX200 serial-speaking scope. Page 59 -has- a "report where we are" section of code. The important lines are: OPEN "COM2:9600,N,8,1,CD0,CS0,DS0,OP0,RS,TB2048,RB2048" FOR RANDOM AS #1 which tells the PC you are going to be doing mixed In/Out from the COM port (in this example, COM2) Then (page 59): ------------ telpos: LOCATE 6, 7: PRINT "TELESCOPE POSITION"; c$ = "#:GA#": PRINT #1, c$; : d$ = INPUT$(7, 1): RAL$ = LEFT$(d$, 3): RAM$ = MID$(d$, 5, 2): LOCATE 9, 10: PRINT "ALT: "; RAL$; CHR$(248); RAM$; "'"; c$ = "#:GZ#": PRINT #1, c$; : d$ = INPUT$(7, 1): RAL$ = LEFT$(d$, 3): RAM$ = MID$(d$, 5, 2): LOCATE 10, 10: PRINT "AZ : "; RAL$; CHR$(248); RAM$; "'"; RETURN ----------- The "PRINT #1, c$" sends the commands GA and GZ to the scope, and " d$ = INPUT$(7, 1): RAL$ = LEFT$(d$, 3): RAM$ = MID$(d$, 5, 2):" reads (INPUT) the COM port and extracts the desired characters from the result. "LOCATE 9, 10: PRINT "ALT: "; RAL$; CHR$(248); RAM$; "'";" puts them on your PC screen. You could have it PRINT to a file. Loop until the balloon is no longer visible... (oh, the good old days when PCs came with BASIC on ROM chips in the machine...). GWBASIC can be downloaded from many sites (just google on "GWBASIC download") including: http://www.geocities.com/KindlyRat/GWBASIC.html have fun --dick
Subject: RE: ETX-70AT with DSI used as a Balloon Theodolite Sent: Monday, March 24, 2008 15:39:11 From: Jim Rogina (firstname.lastname@example.org) Mike, I'd like to thank you for your continued interest and assistance; and thanks (in advance) to Dick Seymour for any advice he might provide. With focus on how you might help us... The most important issue for this project is finding a solution for writing ETX scope position data to a file for analysis. In our limited experience, it appears that Autostar uses standard LX200 scope control code. If we have to do a little embedded systems programming, I won't let this quell AWBC Student enthusiasm, but if we can avoid this more advanced solution simply by purchasing some inexpensive off the shelf amateur astronomer software solution, this would be a better solution for our students; and a dual lesson as well; the fully functional amateur astronomer equipment and software might inspire our students to become amateur astronomers. I can imagine amateur astronomy telescope control software that allows the user to track an unknown object like say an asteroid and then use that empirical data to display the object's track against the celestial sphere; if in the year 2008, no such inexpensive astronomy program with ETX/LX200 telescope control now exists, I'd imagine it's only a matter of time. Meade's Autostar Suite, Starry Night Pro, The Earth Centered Universe Pro, etc.; our research indicates that possibly many others, like for example Daniel Wolf of Videobotics, have made some use of the LX200 control code in their software product offerings. We are hoping that we won't have to purchase and individually test thousands of dollars worth of software to find telescope control software functionality that will allow us to write ETX scope position data to a file. Thanks (in advance) for any assistance you might provide. Following is a more complete discussion of the AWBC project issues; if you want to take the time... you may find this additional information interesting... or not... in any case, thanks again for your time and interest...Jim Rogina I'd like to take a moment to emphasize that this project has a very good cause, www.awbc.info ... We are working with K9-K14 students here in Alaska, trying to use the inspiration of 'Sport Ballooning' to create a context and/or motivation for learning science in the classroom... to inspire students to excel in the sciences, to motivate students to learn how to make use of computers, mathematics, physics and the Internet to negotiate a successful process that might even lead to... of all things; innovation. I have been recently amazed, for example by the scientific community's admonishment of Garrett Lisi, ostensibly because the guy has a "new" Esub8 theory; as if the top scientists of the last several centuries have never been wrong about anything, much less everything. http://www.telegraph.co.uk/earth/main.jhtml?xml=/earth/2007/11/14/scisurf114 .xml When the human ego oppresses the spirit of learning, I speak out against it and try to get the student's focus back on being inquisitive. There is nothing wrong with a student having a theory and trying to solve a problem; even if the so called "experts" disagree. Clearly, I'm no ETX expert, so, in all humility... with regard to the LNT; this is what I was thinking... When Autostar goes to an alignment star during its 'one star' alignment routine, I'm guessing it slews to a position where a particular star should be if the scope were properly aligned; then after the user manually centers this alignment star in the FOV, the user somehow indicates to Autostar that the alignment star is indeed now in the center of the FOV. Autostar can then make the relative corrections to 'Level and North' based on this enhanced information. Enhanced alignment would occur if a landmark like a mountain peak were used. I don't spend much time considering these details, because in my opinion they aren't deal-breakers... if we use the LNT and accept the FOV automatically chosen by Autostar (regardless of scope position) the winds aloft data will have relative errors, errors that can always be corrected in future soundings through a more through scope alignment procedure. It's important of respect the application. By comparison; I have, for more than 35 years, executed thousands of safe successful balloon flight plans, based upon 20 minutes of observed winds aloft data acquired from a simple compass and a wrenched neck. Relative position errors will create relative errors in the sounding data. The students can determine the magnitude and/or effect of these relative errors on a safe hot-air balloon flight plan; and alter their scope alignment procedures accordingly. Most of the theodolite "experts" we have consulted on this subject spend all of their time with us conjuring up and focusing on details to suggest that our concept 'won't work' and discouraging the students from further investigation. In spite of this, we have easily demonstrated 'proof of concept' by acquiring inexpensive readily available 18" latex pibals and tracking them for more than the desirable 30 minutes [$150 ETX-70AT and a 25mm eyepiece]; in fact... if in the final assessment this is the best we can do to automate the pibal tracking process, this manual tracking method is acceptable (certainly as easy as the procedure for aligning and using a $15,000 theodolite). Proof of Concept... Never the less, the discouragement from some of the theodolite "experts" has been overwhelming. Acquisition of the pibal in the ETX FOV, for example, became such a big deal with 'the experts'; any student with a normal sensibility of ego would have given up under the pressure long ago. Luckily, I'd already made the crushing investment in the ETX, may years ago. We made it clear in our discussions with the 'experts', acquisition of the pibal is not important during the first five to ten minutes of the sounding, because during this time, the pibal can easily be tracked very simply, visually, with a compass; allowing plenty of time to get the pibal in the ETX FOV. We explained; Ballooning only happens when the winds aloft are relatively calm; the angular displacement of the pibal during the 30 minutes of tracking might only be in total 15 to 30 degrees. Still, the students are only advised as to why this won't work, not encouraged to investigate further. One of the biggest issues the theodolite 'experts' throw at the students as reasons to abandon our project??? They site the difficulties in alignment of the ETX scope... Why all the discouragement? What are the real deal breakers? * $8,000 to $15,000 for 'expert' theolodite instrument(s) * $6 per pibal + helium costs If we had to endure these costs; there could be no soundings made by any of our students, ever. AWBC needs many concurrent sites for observation. Instead we are suggesting that adequate data can be affordably obtained from a $150 ETX scope and $.02 latex helium pibal balloons...... @ less than 2% of those 'expert imposed' deal-breaker costs listed above. Yes, using readily available cheap latex pibals might introduce errors in the sounding data, however the possibility of these errors doesn't justify scrapping the idea altogether, rather we teach the students to account for those errors and make a determination as to the value of the data that can be gathered from those 'cheap pibals'.
From: Richard Seymour (email@example.com) Whoops... my apologies... the request was a complicated one, so i couldn't just dash off an answer... and it did arrive in the midst of other things going on. It's difficult to determine exactly -what- Jim is requesting. I -believe- he's trying for "object moves in camera field, scope follows" (if not, could you please restate the -technical- "what i want" -without- the surrounding history, mission statement and justification). If "moves...follows" is the goal, then that's really what's behind "autoguiding", a common astrophotographic process. There are many (some free) programs which will provide that function. He is correct in that the ETX-70AT will respond to many LX200 serial commands. If he upgrades his 494 Autostar to a 497 Autostar, there are even more commands available, and they're processed faster (the 494 with the 506 cable/converter is limited to fewer than 100 characters per second. The last time i check it (5 years ago) it was about 67 cps). The 497 (with a built-in rs232 interface) can handle over 900 cps. An example free guiding program is PHD Guider http://www.stark-labs.com/phdguiding.html It uses the ASCOM driver platform to be able to talk to dozens of brands of automated telescopes. It can use the Meade DSI camera as its sensor. Another example is CCDguide (or something like that... i'm not at home with my notes at the moment), which is also free and can accept the (cheaper) Meade LPI camera. ((when i get home, i'll send the correct name)) Since his targets are going to be moving far faster than images drift in the typical astronomical application, he may have to tweak the code to issue commands at a higher slew rate than most guiding programs request. One problem with Meade's cameras is that their CMOS sensor only subtends an angle equivalent to a 6mm eyepiece... so the field of view is -tiny-, and it may be difficult to keep the object in view. (put in a 6mm and try to do it by hand...). Additional optics (such as a focal reducer) may be needed. To simultaneously extract "where is it pointing?" you'll need a method of "multiplexing" the two programs' (guider and recorder) data streams to the Autostar via a single COM port... ASCOM's POTH (Plain Old Telescope Hub) does that. The two programs view POTH as their "telescope", and POTH is the real owner of the COM port that talks to the physical telescope. Likewise, Meade's AutostarSuite has a method (called Network Server) to allow two of its components to share telescope access... so their guiding program (LPI.exe or Envisage) can control the scope, and the scope's path can be traced on their SkyMap application. For numeric analysis, you could capture a simultaneous log of the serial port's data stream (using PortMon, for example) and later extract the desired data. How well Envisage and the LPI.exe program will interact with a 494 Autostar will depend upon many factors (firmware version in the 494, whether Meade allows you to autoguide it, etc.). You may have to lie to AutostarSuite and claim it's a Classic LX200. Daytime alignment of the scope is simple. You could ignore the LNT and simply establish a know due north (or known offset from due north) landmark. Point the scope *there* (with barrel level) and power up. *Skip* the alignment, (after date and time, just tap [mode] to esaape it). Press [mode] 3 seconds, release, scroll to the Alt/Az readout. It should be reading Az=00, Alt=00 and you can take it from there. Feel free to ask for more details. have fun --dick
Jim Rogina wrote: > Thanks Richard, > > You've suggested many options, I'll explain our simple request more > specifically; and address our other issues with order of priority. > > 1) We're hoping to be able to control the scope manually, with selectable > slew rates, all the while writing the 'scope position' data to a file. If, by "manually", you mean by tippy-tapping on the Autostar's keypad, it can handle this. From the PC you'd send :GA# to get its altitude, and :GZ# to get its azimuth. If you do -not- attempt an alignment, these will be relative to where the telescope was powered up. If you limit your interrogation rate to once or twice per second, the 494 should be able to keep up. Sometimes the results may lag the actual position by a bit... this will be murder for your application (that's what smoothing algorithms are for, right?) but it's a quirk of how Meade wrote their firmware. > Regarding FOV; if I have to look through the 25mm eyepiece while controlling > the scope manually, this is an acceptable option. Being able to more > conveniently use the video output from a focally reduced video/web camera, > would be nice, but the simple goal is #1 above. > > If we need to purchase the latest ETX Premier Edition with the 497 Autostar > and built in RS-232, this is an acceptable option; this scope is available > now for less than $600. Five years from now there will be thousands of them > available on ebay, and by then one will cost only $300. You only (may) need to purchase the 497 itself... it will happily operate any ETX telescope (except the original ETX90-RA, which does not have a motor on the DEC/Alt axis). List price for the 497 is now $200, but they're frequently available for $100 or slightly less (with digging). If you have not yet purchased the 506 cable/converter for your 494, the cost of that could be put towards buying the 497. Another advantage of the 497 is that the firmware -can- be patched to change its behaviour. I've generated many custom patches over the years to help projects like this. It's part of the fun of the system. > ***) Again, in other words; I'm hoping to procure a telescope control > program that will control an inexpensive amateur consumer EXT-type scope > manually, with selectable slew rates, all the while allowing us to write > 'scope position' to a data file. Now here we're ambiguous again... if you mean "manually" to be using the PC as the -controller- (click on screen, keyboard or wiggle a mouse/ joystick) then you're adding some levels... there are programs which will do much of this (Andrew Johansen's MyScope has a lot of this... but it's aimed at the additional serial commands available in the 497). But it's certainly feasible to toss together a (for example) Visual Basic program to provide the functionality you desire. You'll only be limited by the command repertoire of the 494 (i'm not sure at the moment what speed control you have available). > If the Autostar 494 is a problem, we'll get the 497. It may depend upon your 494's firmware. You can see the version number by menuing to Setup/Statistics [enter][scroll up] If it's 12Ea, i can find out what serial commands it knows. If it's a newer version, i don't have copies of that ROM to analyze (yet). > If FOV is a problem we'll use the 25mm eyepiece. If telescope > alignment is a problem, I'll deal with it on my own, thanks; I'm hoping that > we make use of your valuable and much appreciated time trying to solve the > problems that are the real deal-breakers. The difference between a 494 and > a 497 is $150. A Meade LNT is $150, a webcam is $150, a focal reducer is > $150... A theodolite it $8,000 to $20,000. We don't care about $300 or > $500, especially if it means that we are going to continue to miss the boat. The ETX70 is quite possibly a better starting point (in some ways) than the ETX90 or ETX125... because it's a shorter focal length/wider field scope. > Auto-guiding the telescope after acquiring the pibal would be a great > feature and I'll be working toward the possibility of this feature as a goal > in the future; but we don't want the complications of auto-guiding or any > other less relevant details to overwhelm the feasibility of the project. In > all humility, I don't know why our inquiries continuously get bogged down > with seemingly endless almost irrelevant details. I apologize; I'm > apparently not able to state the problem effectively. In the simplest terms > we're hoping to be able to control an ETX-style scope manually, with > selectable slew rates, all the while writing the 'scope position' data to a > file. If we can't do this one simple thing, every other discussion on this > subject is totally useless. Tracking where it's pointing, with user-program-supplied timestamps, is relatively simple. Andrew's MyScope can do that... you can tell it serial commands to output at what rate, and it will log the results. Writing a similar application in (insert your favorite language) isn't too hard, depending upon (your favorite language)'s facility with bidirectional communication via a serial port. If memory serves, in Visual Basic it's just opening COM1: as a file for read/write, for binary access or record lengths of "1". The Autostar's terminating character is the "#", it does not emit "carriage returns" as terminators. (so a simple "readline" doesn't work). Adding "manual" control via the PC becomes an exercise in interface design (for talking to the human), and sorting out which commands the 494 accepts. The "talking to human" portion can indeed be a long drag into "irrelevant" areas... have fun --dick
Whoops... forgot to include a few references: Andrew's MyScope is available from http://members.optusnet.com.au/johansea also check out his "MyVideo", which includes Autostar control -and- video processing. He wrote those in Delphi, and is quite happy to attack interesting problems. The Official Meade LX200 command document is here: http://www.meade.com/support/LX200CommandSet.pdf There are dozens of newer commands -not- documented in that, but the 494 probably doesn't have them, either. have fun --dick
Thank you, Mike and Richard Clearly, there are many ways to skin this cat. I appreciate... the time you've given my inquiries on the subject; and your patience with my frustrations. My requests may seem ambiguous, I'm sure from your perspective they are. For example, I'm not sure if it's best to control the scope from the Autostar hand controller, or the keyboard of some other device; one of many issues, one of many choices, each with their own set of decision parameters and complications. Clearly, I don't know the best configuration solution for the equipment, and so I'm not able to specify what 'exactly' I'm trying to do succinctly... To this end, I've tried to provide enough background to emphasize the important issues in designing/innovating a ballooning theodolite; while rejecting discussion on those issues that are not important. I think that I've read in your responses in several places that there is indeed software available that will log scope position and write to a file. Thank you. I'll be looking over your suggestions over the next few days and, if you like, I'll keep you posted as to my progress. Of course, if you should think of something in the shower, I'd love to hear about your refined innovative ballooning theodolite ideas. Making use of my old ETX-70AT scope equipment is not as important to us as being able to repeat what ever solution we finally choose... we (AWBC students) intend to acquire/make several of these balloon theodolites in the coming months. Thanks Again, Jim Rogina
Subject: Vista connection ETX60/70/80 Sent: Saturday, March 22, 2008 04:48:21 From: Henrik van Holthoon (firstname.lastname@example.org) As Mike said you need #506 serial cable one side goes into the AUX port on de control panel of the ETX60/70/80 other side to serial port PC or serial/USB adapter. I use Autostar suite software in combination with ETX70AT together with Vista no problem it works without any problems. For the rest follow Mike's advice. Regards Henrik
Subject: RE: ETX-70AT with DSI used as a Balloon Theodolite Sent: Friday, March 21, 2008 12:15:03 From: Jim Rogina (email@example.com) I've read up on focal reducers, thanks. I'll know more about the magnitude of my FOV issues after I test drive the DSI. I read with interest your suggestion regarding the Autostar #497. On the Meade site they list the 'additional capabilities' of the #497... For example... "Digital readouts of telescope position, continuously in RA and Dec." This sounds like what I'm looking for; but there are no details; I can be sure what they mean. Daniel says that he stopped development of his CamMotion software CIRCA 2001. The advantage of working with his software is the less expensive equipment; maybe an old ETX, an inexpensive Webcam and his software might be sufficient. On the other hand, technology marches on. I'm thinking that maybe I should consider purchasing one of the newer Premier Edition ETX scopes. The LNT features will be very useful in my application. The PE scopes come with #497. Do you know of a way to get the advertised 'Digital readouts of telescope position, continuously in RA and Dec'? I need to create a track log... scope position history (file). Thanks for your advice JimMike here: There is AutoStar programming info on the Helpful Information: AutoStar Info page. As to the LNT, that may or may not be useful. Once the LNT completes its "North-ing" and leveling it will slew to an alignment star. You probably don't want that.
For my purposes, (daylight terrestrial tracking of a pibal) exact scope alignment is not important; yet the scope must be approximately aligned or the scope position data file might be (relatively) compromised beyond being useful. The LNT simply automates the approximate leveling and North-ing tasks; I'd simply accept its alignment star position and move on with my pibal tracking efforts. With the old ETX-70AT, I'd level and align the scope manually and accept the one star alignment routine. I've read much of the Autostar programming info on your site; clearly, you have lots of experience with this subject. My first approach is to see if there isn't something built-in to commercially available software that will serve my needs; and this is where I'm hoping your experience might be helpful. The DSI I purchased comes with Meade's Autostar Suite. I see a dialogue box for the "Obsevatory Dome Controller" on which I see a field for a Log File; ostensibly presented in the context of 'keeping observing logs'. Upon further investigation reading the AutostarSuiteManual.pdf I read: "In addition to controlling the observatory structure, the controller also keeps a running log of telescope pointing, air mass and auxiliary instrumentation in the Log File. The name and location of this file can be set from the main window. For complete information configuration and operation of the Observatory Control Module, see the documentation for the Observatory Controller Box." It's difficult to determine what might or might not be a real feature from reading Meade's advertising. Of course, I can't find any documentation for the "Observatory Controller Box". If I use Autostar Suite to control the scope, will I be able to keep a log file of scope position history?Mike here: Well, you might be better off using a landmark (which can be "marked" in the AutoStar). This would work if you always work from the same (or known) locations. The problem with the LNT could be that it doesn't necessarily end up pointing North and being level at the completion of the North-ing and leveling. But if you let it go to the first star and then abort out (if you can do that from software) then you would still have to slew to some known position, like az=0 and alt=0. Dick Seymour is our resident expert on AutoStar software so I'm adding him to this thread for his thoughts.
Subject: ETX-70AT with DSI used as a Balloon Theodolite Sent: Friday, March 21, 2008 01:15:48 From: Jim Rogina (firstname.lastname@example.org) I design, build and fly hot-air balloons in Alaska. A standard pibal theodolite http://www.pilotballoon.com/balloon.htm can be a very expensive [$8,000+] and tedious instrument to use http://en.wikipedia.org/wiki/Theodolite ; an ETX with a Web camera can be had for $300. Many years ago I purchased an ETX-70AT, hoping to be able to track pilot helium balloons for mountain flight plan winds aloft verification. www.awbc.info My concept is to use the ETX drive controls, a video camera, and a laptop to track a helium balloon. I purchased a Meade DSI this evening [~$160]; I'm sure I'll learn something for my money and trouble. In my feasibility test, I was at 14X magnification ~[350mm/25mm], now with the DSI I'll be at 350x; twenty five times that magnification... I've been in contact with Daniel Wolf at www.videobotics.com he has created a rudimentary program [CamMotion ETX] that uses an ETX as a Webcam directional control platform. From what I've been able to read, it looks like Meade's software will control the scope OK, in fact it might even auto-track the pibal if I can get it into the field of view with some reasonable focus; but my problems will continue be the reduced FOV, and writing the drive control's data output to a file. Maybe Daniel Wolf could/will help with the data-file issue; I don't think Meade will be very helpful. Do you have any suggestion regarding the Field of View problem I'm going to have? Can I somehow install a lens before camera to reduce the magnification? Thank you in advance for any assistance you might provide. Jim RoginaMike here: Interesting idea. You could install a "focal reducer" before the DSI. Best results would be with one designed for the ETX. One other point is that you might need an AutoStar #497 (the ETX-70 came with a #494, which doesn't have number keys). But that would depend on Daniel's software.
Subject: ETX 60 AT want focuse Sent: Thursday, March 20, 2008 06:13:39 From: Charles Powell (email@example.com) My new ETX 60 AT does not look like it is focuseing when the nob is turned. Do you know how to check it? CharlesMike here: It can take many many many turns of the knob to focus, depending on where the objective lens housing is positioned. When turning the knob you should be able to see movement (very small though) in the lens housing as it slides up or down the tube. Try focusing on a distant terrestrial object.
Subject: azimuth drive failure. No spring? Sent: Tuesday, March 18, 2008 17:14:46 From: Jack Porter (firstname.lastname@example.org) The azimuth drive on my ETX-60 ceased working. The azimuth drive motors work as expected, and with plenty of torque. The azimuth drive lock lever felt loose in all positions so took the scope base apart. Don't know how it happened, but it seems the drive lock screw needed resetting, which I did by taking the lever off of the hex bolt, tightening it to just the right tension. Now the azimuth lock works fine. On re-assembly the azimuth drive motor works fine, but doesn't move the scope in azimuth. I realize now that the azimuth drive worm gear is not engaging the large (nylon) gear in the base - the one which is friction engaged to the base by the azimuth locking lever. This time I discovered that the whole azimuth drive worm gear assembly is swung on an axis and needs something to push the worm plus worm assembly against the large nylon gear. My guess would be that it is a spring, but there is no such animal in my scope now, and I have never had it apart before! Please answer following, if possible: What is the part or information I am missing. That is, what is supposed to press the worm against the big nylon gear? If I am missing a part, as I suspect, how can I get a replacement? Or, if that's a hassel, Can you describe the part so I might fabricate it? Thanks, Jack Porter.Mike here: Don't know if this will help but check the article "ETX-70AT Repair Guide" on the Helpful Information: Telescope Tech Tips page.
Subject: Ext-60at USB connection Sent: Thursday, March 13, 2008 19:19:42 From: Timothy Wood (email@example.com) I have the ext-60at and have the autostar software that came with it. I don't know what cables I need to connect it to my laptop. I have looked online but haven't seen what cables I need. Any help? -Timothy WoodMike here: You need two things: the #506 serial cable for the ETX refractor models AND a USB-serial adapter (assuming your computer does not have a RS-232 serial port). Note that not all USB-serial adapters work well with the AutoStar. You could go with the Meade adapter or see the article "AutoStar and USB" on the Helpful Information: AutoStar Info page. As the #506 serial cable, it is a not a cable you can make yourself. It comes with the Meade astronomy software package. Alternatively, if you get a #497 AutoStar you can easily make a #505 serial cable using instructions on the AutoStar Info page.
Ok, I looked it up and I see that for the meade cable the driver software is not compatible with windows Vista, which the the OS I am working with. Any solution? Also I am wondering if after I connect the 60at with my computer (with autostar software running) will it automatically connect and I will be able to control the telescope? Or will I have to run an update on the scope/computer? -Timothy WoodMike here: Yeah, Vista is a... Well, I'll be nice! Anyway, other adapters discussed in that article probably have Vista support (although I don't use Windows when I can help it so don't know from personal experience). Keyspan has adapters that seems to work best with the AutoStar. And yes, once you have the connection you can control the telescope from the computer. There are many excellent commercial, shareware, and freeware applications. For a couple, check out Scopedriver and AstroPlanner (discussed on the Accessory Reviews: Software page).
Two more questions! Does the cable plug into the hbx port on the base of the scope itself? Or does it go into the aux port? If so, will the autostar on the scope try to compete with the autostar on the computer? Second, what is the difference/advantages of using the supplied autostar software vs. Buying the astrofinder software? They sound like the same thing to me -Timothy WoodMike here: With the #506 cable and AutoStar #494 (no number keys) the cable connects to the AUX port on the ETX-60/70/80 base. With the #505 cable and the AutoStar #497 (has number keys) the cable connects to the RJ11 jack on the AutoStar itself. The AutoStar software (on the handset) provide a lot of capabilities without needing a connected computer. However, if you want to control the telescope from the computer then you will need some telescope control software running on the computer.
Subject: My Meade ETX-80AT Sent: Monday, March 10, 2008 14:03:11 From: Dave Pople (firstname.lastname@example.org) I have just bought a Meade ETX-80AT with Autostar I have read the booklet and tried to get the Autostar to find me some interesting items. However when I click align the Telescope goes through some configuration and seems to find the constellation it was looking for. The telescope then says it's slewing and starts to make a noise like my mother in law is stuck in the boot of my car and does not move around any more. When I first set the scope up I set the direction to north and set the angle at 0 degrees. Am I doing everything right? I have made sure the locks are secure but not too tight Any advice or help would be good-thanks DaveMike here: Several points. Be certain you have done a CALIBRATE MOTOR and TRAIN DRIVES. Be certain you do not overtighten the axis locks. When setting the tube to 0 degrees, don't necessarily rely on the scale on the fork arm; it could be misadjusted. The tube should be level, regardless of what the scale says. If you want to correct the scale, see the FAQ page on my ETX Site.
Subject: mySKY and my ETX-80) (AT?) Sent: Sunday, March 9, 2008 12:25:05 From: Eric Vidacovich (email@example.com) I have an ETX-80, I believe that it is an AT, with the original controller. Apparently, I am somewhat of qn optimist, because I keep working with the scope with small results. I recently purchased a mySKY hoping that somehow this would assist me in a number of issues. After reading the instructions, I'm still not sure how to hook it up to my telescope or if I am putting it in the proper position for setting the GPS. When it says to set it on a stable surface with the top pointing at the sky, does the top referring to the front part or the top with the 3 lights. This seems that it should be a simple question and probably is. The main issue is, can I use it to move my telescope where I point the mySKY? EricMike here: Read my review of the mySKY on the Accessory Reviews: Showcase Products page. The "top" means the portion with the three lights. As to connecting to your telescope you will need the special cable for the ETX-60/70/80 models. That comes with the Meade mySKY Cable Set I discuss in the review.
Thanks, I have the cables already. Eric
Subject: Autostar 497/494 question Sent: Friday, March 7, 2008 09:08:30 From: Jack Fox (Jack.Fox@vdacs.virginia.gov) Can the 497 Autostar be used to control the ETX -70? If so, do you have to recalibrate and retrain the motors each time if you switch between controlling a ETX 125 and the 70 using the same Autostar? Do you need to tell the 497 under Telescope model menu that it is a 70? Jack FoxMike here: Yes, it can control any model ETX. You will have to CALIBRATE MOTOR and TRAIN DRIVES each time you switch telescopes. You can switch the telescope model if you want to have the optical calculations be correct for that telescope. Remember to switch the mounting mode if that changes.
Subject: ETX 70 with 495 handset upgrade Sent: Friday, March 7, 2008 08:12:02 From: David Hofland (firstname.lastname@example.org) I have a friend who has an ETX 70, an older model from a few years ago that the instruction book he has only includes operation instructions for the handset that came with it, which was at that time one without autostar, just an alt/az motor controller with up-down and left-right control. But in his box, I guess his wife got it used form somewhere, he doesn't have that original controller, instead he has a 495 handset. Now I have a new ETX 80 (2007 model) with a 494 handset, so he asked me to help him set his up as I am familiar with that basic operation. Problem is that on his 495 controller handset there is no "speed" button to change the slew speeds. So during alignment, when the scope needs to be slewed to center the alignment stars, the slew arrows work but the speed is set on the slowest possible speed and it is barely moving, too slow to reasonably operate it. Anyway, he has no instruction book, and I tried pulling up every mode and menu and could not find how to change the slew speed. I checked the Meade website manual download page and found nothing for the 495 handset. My handset 494 has a "speed" key, but his 495 handset does not. Any ideas? David HoflandMike here: You can use the number keys to change the slewing speed (9 is the fastest and 1 the slowest speed). You might want to consider (in fact you might have to) upgrading the #495 to a #497. Just installing the latest Meade software will do that.
Thanks, I will let him know
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