Results 1 to 5 of 5
  1. #1
    Join Date
    Dec 2010
    Posts
    1,422

    Default My observatory suddenly quit working it had been fine forever HELP

    This is a guide post to help those who run into this all together COMMON situation.

    What do you do when things have been running and now for unknown reasons they are NOT running? Where do you begin?

    First, this WILL happen to all of us eventually so take heart its COMMON.

    Secondly, ask yourself what has CHANGED? What MIGHT have changed, well plenty. Here are some common issues

    New Windows update, yikes always a problem!
    New ACP, ACPS, TSXPro, FM, ASCOM driver, you put in new software NOT related to astronomy, new computer, new USB hub, new video camera, new firmware in some piece of gear, new gear, you decided to re teather your cables, its now WINTER, its now SUMMER, it just rained for a week, its been DRY for a week, you had GUESTS in the obs, YOU were in the obs, MICE were in the obs

    Guests by the way LOVE to touch things, YOU were in the obs and bumped something, tugged something, don't even begin to tell me this hasn't happened already to you!!

    Lets say NONE of that is true!!! This is still COMMON!!!!

    So, if their were no changes other than the obs just quit working now what?

    Begin a logical attack. ACP and many programs provide a GENEROUS number of simulators. You probably haven't used them but wondered how they could help, well they are fantastically helpful at isolating problems.

    You may or may not have an idea of what's caused this failure. Lets begin with the easier one, lets say you DO HAVE an idea. Your Dome suddenly quit working properly. Lets say the shutter will not close but the dome moves and stays with the scope. So, in this instance you already know a ton, you now know the communications wires, hubs connectors are all good since the dome tracks. This is an important concept that you should apply to ANY failure you have. In other words it a PIECE of your hardware teathered to another piece works you have already isolated the issue considerably. Take a step back for a moment and consider what's just been observed. You already know a ton but if you don't take a second to think about it you may over look what you DO KNOW. Over looking what you DO KNOW is a common mistake in our haste. You now know that the hardware leading to the shutter is all good, computer, wires, hub, software and so on. In this instance you would immediately pursue a hardware issue, broken spring, tension wire and so on.

    Lets make it a little tougher, lets say your dome and shutter no longer respond, this scenario could be applicable to ANY piece of gear going down. Now things are tons more difficult. Lets add one more piece to the puzzle, lets say as is very common, your dome is off a USB hub with other gear on it. The other gear appears to work just fine. Now what do you do? First, a visual inspection of the hardware and cabling of course MUST be done. Again, this inspection applies to any scenario where their is an abrupt failure, don't under estimate environmental changes!!! If I have had one device that has let me down more than any other I can say without a doubt that its been USB hubs. MANY times, they "sorta" work. Drives me nuts!! Why would one port crud out? I have no idea but I have seen this half a dozen times!!! How do you prove it? Boy you'd think logic would apply, like swapping the Dome port for say your camera which is working, that should expose it right? Well not always. One technique I have used is to substitute those simulators for equipment on the hub. I actually UNPLUG the other gear and put a simulator in its place. If all that gear is off the hub, and all that is left is the failing piece that keeps on failing then I can safely conclude the OTHER gear is NOT adding to my problem. This is important if you are concerned that other equipment may be malfunctioning and corrupting the process. This is a subtle but important point. ACP for example talks to subsystem "A" if subsystem "A" fails it might lock up other subsystems. So, what you THOUGHT was the dome not responding was in fact some OTHER piece of gear that died and then the last domino to fall was the dome not responding. This is the most treacherous of problems!!! So, by removing all the other gear and substituting a simulator you remove the potential interaction. Lets say you remove everything from your USB HUB, and leave only the Dome. You now use the simulated OTHER equipment and your Dome suddenly WORKS, ah ha!! You now just start adding back hardware one at a time until you reproduce the fault and you'll find your problem. MAYBE!!! Lets say you add back your auto guider, and eurica, the dome fails. WHAT is the cause? Well, is it, the USB HUB, Cable to Augtoduider, cable to dome, the auto guider itself, a ground loop????? Now you need to begin replacing pieces one at a time. So, change the USB HUB ...by the way DO NOT make wholesale hardware changes all at once .... DO NOT DO THAT.....WHY, because you MIGHT fix the problem but you will never know WHY it failed in the first place and it may happen again. Further, you start dumping all sorts of new hardware into the equation you just increased the potential for new problems by a zillion, actually I think the equation is X times (x-1) times (X-2).....till one. Wanna have a nervous breakdown!! ONE piece at a time, so maybe the USB HUB, then cable and so on. Sooner or later your going to find the culprit.


    Remember all those variables up front, weather temps, mice yadda yadda yadda.....TEMPERATURE and HUMIDITY are serious and often under appreciated problems. Believe me I know!! Consider what your observatory looks like at 4 am. NOT day time when you are in there. THINK about how the dew might lay across that gear, think about the temperature change at night, often 25 deg F or more different. Would DEW settle into those nice little holes in your gear, hubs etc??? Would the contraction of the USB connector disrupt things? Serial connector, sure you had those screws tight? Did you use LOCK TIGHT???? Constant temperature changes make for a mess!!!! The constant cooling and warming of plastic and metal parts DOES CAUSE THEM TO MOVE. Do not underestimate how much things change. A regular inspection of all your joints will save you hours of agony. I do this monthly, and STILL I get hosed occasionally!!

    Mice love cables, enough said just remember to look.

    WATER, mans best friend except when it crept underneath the wall of the obs and you didn't notice, ooops. Hidden behind that pile of "stuff" or under the computer, power switch HUB or whatever. MOVE stuff around from time to time and LOOK for it, you just might be horrified at what you find!

    To sum up, common things happen COMMONLY!!! So, thinking logically about this abrupt failure,

    WHAT has CHANGED????
    If nothing changed then you already know a ton!! SOFTWARE doesn't RUST!!!
    Do a thorough visual inspection.
    THINK about 4 am and what it might look like, that means dew that means WHAT POSITION was the equipment in?????? Did the cables get moved in a way you didn't expect??? Snagged, loosened, cable tie break mice, screws moved due to constant temperature changes, water????

    Do the WALK AWAY !!! Probably the least used and most effective tool I have ever had!!! Sometimes just a day of NOT thinking about it....cause of course in back round you ARE thinking about it, is all it takes to come to a eurica moment. Its HARD to discipline yourself to do it, you WANT IT working NOW. But, that one down day can be a game changer.

    Well, if none of this helps you, I would do as a friend suggested recently LOTS OF JACK DANIELS!!

    I hope this was helpful
    Peter

  2. #2
    Join Date
    Feb 2012
    Location
    Charlottesville, VA
    Posts
    885

    Default

    Hi Peter:

    Thanks for your post. Here are a few other practices that have helped me at my observatory:

    1) Keep a logbook, and log every change that I make. This has been very helpful. Sometimes a very innocent change can cause a problem a week later. In a recent case I updated by SBIG driver and broke my system so that I could only connect one camera at a time. (It was a bug in the new driver.) So having all of the changes documented narrows down the list of what can be causing a problem. I also try to document solutions to problems so that I don't have to recreate them a year later.

    2) Make one big change at a time. For example, I would test a SkyX Daily Build before trying to upgrade SkyX, FocusMax and ACP on the same day.

    3) Keep hard drive backups. (Peter, as I understand your observatory you run dual computers). I have a hard drive set up to create an incremental backup twice a week during the daytime at 9:30 a.m. Approximately once per month I create an "Image Backup" of the whole drive. This came in handy a few months ago when I fried the motherboard on my CPU. I was able to slip the hard drive out of the computer, purchase an identical computer on ebay for about $250 (because it's a year old machine it was very cheap), slide the old drive back in and bring EVERYTHING up without having to reinstall ANYTHING. Amazing! That worked so well that I purchased another identical machine on ebay (I waited for a deal and got one for less than $200 because I was no longer desperate) and routinely install an image backup in it so that I always maintain a spare computer. This can protect you from a ton of badness.

    I've always dreaded dealing with two problems: having my observatory go bad and having my shutter pulley fail. Both happened in the past six months, and the recovery wasn't as bad as I thought.

    If folks are not backing up their observatory computer, my advice is to go out today and buy a backup drive and just make it happen.

    All best,

    Rob
    Rob Capon
    (Self-appointed) "Executive Director"
    Stillhouse Mountain Observatory
    Charlottesville, VA
    ----------------------------------
    RCOS 12.5 with SBIG STL11000M
    Televue NP101is with SBIG ST8300
    Paramount ME with SkyX
    Techn. Innovations PD10 with Digital Domeworks
    Robofocuser
    ACP with MaximDL and FocusMax

  3. #3
    Join Date
    Dec 2012
    Location
    Southern Oregon
    Posts
    81

    Default

    Thanks for the reminder - just made a complete system backup, first since last September!

    Sean

  4. #4
    Join Date
    Oct 2005
    Location
    Mesa, AZ
    Posts
    33,149

    Default

    Another Peter Prendergast classic!!! This is really priceless sir. THANK you from the bottom of my heart. When I get back in the office Monday it's going the stickies for the company & products section.
    -- Bob

  5. #5
    Join Date
    Oct 2005
    Location
    Mesa, AZ
    Posts
    33,149

    Default

    I would add that the most powerful problem solving tool is to exclude things first, in order to narrow down the possibilities. If you're lucky you can exclude everyting that it could be, except one, and that is it! Usually you're not that lucky, but excluding the things it can't be can really speed up the process of finding the problem. I never read Sherlock Holmes, but I've been told that he said the same basic thing. My life has revolved around it.
    -- Bob

 

 

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. A plug for a fine photometry program
    By George Sjoberg in forum General Astronomy-Related
    Replies: 0
    Last Post: Nov 6, 2013, 14:45

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •