Loading ...
Sorry, an error occurred while loading the content.

Re: [LX200GPS] Re: My lx200gps is going mad, RA not moving at all...

Expand Messages
  • John Mahony
    ... In an earlier message, he said he had tested the wires with an ohmmeter. -John
    Message 1 of 36 , Jan 1, 2010
    • 0 Attachment
      ----- Original Message ----

      > From: autostaretx <rseymour@...>
      >
      > From the symptoms, i would check the cables inside the base
      > to the RA card.
      > "Moving by itself" and "not moving at all" happen if the RA motor
      > card cannot "hear" the main computer card.
      >
      > You have to test each wire, end-to-end

      In an earlier message, he said he had tested the wires with an ohmmeter.

      -John


      > Also look for "cold solder joints" or loose pins where the
      > connectors attach to the circuit cards.
      >
      > good luck
      > --dick
      >
      > --- In LX200GPS@yahoogroups.com, "sheng" wrote:
      > >
      > > I check the RS232 wire last night, and it's the bad of the wire. After open
      > the DB9 head, I found one of the wire get broken. After fixing it, I can connect
      > my computer to it. :)
      > > But the RA problem is getting more strange. Last night I powered it on, the RA
      > slewed by itself, it MOVED!!! But I can't control the RA with Autostar. Then I
      > shut it down and restore the power, RA not move anymore... nor can I control it.
      > I tried to control it through my computer, but I can only control the DEC. I
      > tried to directly talking to the telescope with command ":Me#" and ":Mw#",
      > nothing happen (It worked before). But the telescope has response to the command
      > ":Mn#" and ":Ms#".
      > >
      > > Here is what I think, am I right?
      > >
      > > 1. firmware (v 4.2g): not sure.
      > > 2. Serial input chip: maybe is OK.
      > > 3. Power panel: seems OK?
      > > 4. RA motor driver: maybe there's a problem. I didn't see anything burnt...
      > > 5. Motor encoder: not sure.
      > > 6. Motor: should be OK.
      > >
      > > I will try to flash another firmware to check whether it's a corrupted
      > firmware issue tonight.
      > > Thank you!
      > >
      > > --- In LX200GPS@yahoogroups.com, John Mahony wrote:
      > > >
      > > > Is this scope permanently mounted? Has there been a lightning storm
      > recently in your area?
      > > >
      > > > I'm not sure about the GPS models, but on the old LX200 classic, the
      > "MAX232" chip in the RS232 electronics was susceptible to lightning damage if
      > the scope was permanently mounted, and the scope was left attached to an
      > external computer. That could also explain your RA problem.
      > > >
      > > > -John
      > > >
      > > >
      > > >
      > > >
      > > > ----- Original Message ----
      > > > > From: sheng
      > > > > To: LX200GPS@yahoogroups.com
      > > > > Sent: Mon, December 28, 2009 11:19:18 AM
      > > > > Subject: [LX200GPS] Re: My lx200gps is going mad, RA not moving at all...
      > > > >
      > > > > Hi John,
      > > > > Thanks for your reply.
      > > > > I just upgrade the firmware before this problem coming out. But I didn't
      > turn on
      > > > > the "RA PEC ON". The RA/DEC move randomly at their full speed. But right
      > now, I
      > > > > can only control the DEC, the RA doesn't move at all.
      > > > > And I found another problem with it. I can control the telescope with my
      > > > > computer through RS232 port just after I upgrade its firmware. But today I
      > just
      > > > > found I can't control it through the RS232 port anymore...
      > > > >
      > > > > --- In LX200GPS@yahoogroups.com, John Mahony wrote:
      > > > > >
      > > > > > ----- Original Message ----
      > > > > >
      > > > > > > From: sheng da
      > > > > > >
      > > > > > > Hi
      > > > > > > I have a LX200GPS. Recently the telescope seems going mad. At the
      > beginning,
      > > > > the
      > > > > > > RA/DEC randomly move when I power it on.
      > > > > >
      > > > > > Can you be more specific? How fast does it move?
      > > > > >
      > > > > > The scope usually moves (slowly) in RA when you turn it on. It's
      > looking for
      > > > > the PEC sensor. If you didn't used to use PEC, but just recently trained
      > the
      > > > > PEC and turned "RA PEC ON", then if it was off before, it wouldn't have
      > made
      > > > > that move before, but will now. Or if you recently upgraded from old
      > firmware,
      > > > > it moves a lot more than it used to, so maybe you just didn't notice this
      > > > > before.
      > > > > >
      > > > > > -John
      > > > > >
      > > > > >
      > > > > > > And from few days ago, the RA stopped
      > > > > > > moving totally, but I can control the DEC with my autostar handle.
      > > > > > > I opened up the base board and checked the wires inside, they seem
      > fine.
      > > > > > > Any one know what's going on? Is it possible circuit gets burnt? How
      > to
      > > > > examine
      > > > > > > the source of the problem?
      > > > > > > Many thanks to you!
      >
      >
      >
      >
      > ------------------------------------
      >
      > Yahoo! Groups Links
      >
      >
      >
    • johansea
      Gday Sheng As per my prev post, i have two semi dead motherboards. One appears to use inductors and the other appears to use resistors in the clock/data lines.
      Message 36 of 36 , Mar 25, 2010
      • 0 Attachment
        Gday Sheng

        As per my prev post, i have two semi dead motherboards.
        One appears to use inductors and the other appears to use resistors in the clock/data lines.
        Just for info, what is the rev of your motherboard?????

        Andrew Johansen Melbourne Australia

        --- In LX200GPS@yahoogroups.com, "sheng" <singleye_512@...> wrote:
        >
        > Hi Bruce,
        > It should be conductible. So ohmmeter will show a very small number or 0.
        > Your problem maybe not exactly the same as mine. You can follow the schematic to test all the 6 wires of J8. Make sure the wires are conductible end to end. You can find the schematic here: http://tech.groups.yahoo.com/group/LX200GPS/files/LX200GPS%20Schematics/
        > Check "MainBoard-IO.pdf", you will find how the J8 is connected with U11. You will probably find some wires are connected with inductors. For my case, it's the 3rd wire of J8.
        >
        >
        > --- In LX200GPS@yahoogroups.com, "watsonbw61" <watsonbw@> wrote:
        > >
        > >
        > > Sheng,
        > >
        > > Thank you so much for your reply. It was your original post about this issue that has helped me get this far. I suspected that your power panel problem would eventually come back if it was anything like mine. I'm happy you have a good working scope again, and I hope your info will lead to a fix for me. I will test the Inductor L10 after finding the schematics. What readings on your ohmmeter indicated a problem when you tested your board? Do you have a part number for L10?
        > >
        > > Thanks again, Bruce
        > > --- In LX200GPS@yahoogroups.com, "sheng" <singleye_512@> wrote:
        > > >
        > > > Hi Bruce,
        > > > I had the the same problem with you. As I'm in China, it will cost me a lot of money to return to meade. So I decided to fix it myself.
        > > > After many tests I found when I take the power panel off, the problem is gone. When I install it back with tight screw, the problem is back. So I just insulate the screw and the power panel. It seems OK. I think it's the same as to loose the screw a bit.
        > > > After doing this, the scope worked fine for me till someday I decided to take out the power panel to look at it. What a bad idea it was. The telescope was not under my control from then. No matter I loose the screw or took the power panel off, it didn't work.
        > > > Then I looked at the schematics which you can find in the "Files" of this group. I tested the wires on the PCB. I found the source of the problem is the inductor "L10". I asked my friend to help me changed it. It works perfectly no matter how hard I tight the screw.
        > > > I think you should test your PCB. It's easy to test just with ohmmeter. You can focus on the part between "J8" and the "U11". You can find the print on the PCB.
        > > > Good luck!
        > > >
        > > > --- In LX200GPS@yahoogroups.com, "watsonbw61" <watsonbw@> wrote:
        > > > >
        > > > >
        > > > >
        > > > >
        > > > >
        > > > > Thanks for the posts, as they have been helpful with a problem I'm working on, and I believe I may know what's wrong. Here's what's been going on. I have owned a used 10" LX200GPS, F6.3 for about a week now. I was told it worked perfectly and in a short test run before deciding to buy it, it did. I found a flat spot on two teeth in the RA drive, so it looks like a gear upgade is in order (slight thumping noise, but it still drives). But beyond that I have been working on trying to align the scope between clouds over the last several nights with no success. At times I would get a motor stall error message, while at other times the RA motor would slew to the East without stopping. I have searched this group and the "Classic" group for ideas and did the following as suggested:
        > > > >
        > > > > First I checked all connectors, and decided to solder the wires to the two pin power connector for the RA motor. It seemed to work on the bench, but after reassembling outside the problems came back.
        > > > >
        > > > > Next I inspected as many solder joints as I could. No apparent issues there. I ohmed all the wires I could, again no problems found.
        > > > >
        > > > > Firmware was at 1.6b, so I upgraded to the latest, and half way through the RA motor started traveling again. It took some doing, but I was able to update the firmware, but it did not fix my problem.
        > > > >
        > > > > Next I found this thread regarding the possibility of a short between the power panel board and the mount. I removed the panel and bench tested. It worked perfectly! I insulated all edges of the PCB that looked like they might be able to make contact, but after reassembling the problem persisted. I must have spent three hours using tape, rigid plastic sheets, etc. trying to insulate the board to no avail. I decided I must not be able to see everything, so I removed the power panel board from the metal panel (only four round screws for the jacks). It all worked fine in the air and I could not see any short circuit possibilities there. Upon reassembly I could not get the RA motor to turn on at all, ever, even with the power panel out of the mount. I took it apart again and with the board and panel separated and out of the mount the RA motor worked normally again. At this point I decided it wasn't a short circuit I was fighting, but a bad trace, bad solder joint, or cracked board. I'm guessing that when the board is slightly flexed when attaching it to the panel, or installing it into the mount, or plugging a cable in, or... that a circuit is being "broken" causing a loss of power to the RA motor, or more rarely, motor run away.
        > > > >
        > > > > This afternoon I called Meade to ask if I could order a replacement board, but was told I would have to ship the entire scope to them for repair at a cost of $450 plus freight to their location. I declined, as I just shipped the scope from where I bought it in Costa Mesa, CA to my home in WA State, and there's no money in the budget for that right now. Nor does it seem to be cost effective, even if I had the spare cash.
        > > > >
        > > > > Tonight, even though it is mostly cloudy, and with a fair bit of finesse in handling the scope/power panel I was able to align the scope and use the "Goto" feature with reasonable success. I only had the motor runaway once, so I loosened the screws on the power panel a bit more to relieve the "flex" in the board, but I'm sure this isn't the best way to continue using the scope.
        > > > >
        > > > > Could "Sheng" also have this type of problem rather than a short circuit? Maybe if his problem returns this will help him. Does anyone agree or disagree with my thoughts? Can I just buy a new board somewhere? Can it be repaired? Other ideas? I'm new to this scope and to this forum, so any help will be greatly appreciated. Thank you!
        > > > >
        > > > > Bruce
        > > > >
        > > > > --- In LX200GPS@yahoogroups.com, "autostaretx" <rseymour@> wrote:
        > > > > >
        > > > > > You are correct that none of the exterior metal (power panel, body casting) should be making electrical contact with the circuit cards or electronics.
        > > > > >
        > > > > > On my scope, all of the sockets going through the power panel have insulating washers or bushings, and all of the screws securing the circuit cards have no conducting "circuit traces" touching them.
        > > > > >
        > > > > > Inspect carefully to find what is actually doing the "touching", and insulate it. A "soft" plastic, such as a plastic bag or black electrical tape, may "creep" over time and allow the touching to resume in the future. Use a stiff plastic.
        > > > > >
        > > > > > good detective work
        > > > > > --dick
        > > > > >
        > > > > > --- In LX200GPS@yahoogroups.com, "sheng" <singleye_512@> wrote:
        > > > > > >
        > > > > > > Hi guys,
        > > > > > > I think I found the problem.
        > > > > > > I accidentally remove the 4 screws which attach the power panel with the mount body, and I can control all the motors with no problem. Then I think maybe the power panel and the mount body should not be electronic conductable. I did some test to prove this:
        > > > > > >
        > > > > > > 1. I try to attach one of it, when I screw it tight the RA motor stopped moving.
        > > > > > >
        > > > > > > 2. I push hard on the part where the screw is attached on the power panel, sometimes the RA motor will stop moving.
        > > > > > > Then I use some plastic sheet to isolate the power panel and the mount, I also isolated the screw and the power panel, the telescope is back to normal!
        > > > > > >
        > > > > > > I think it maybe a design issue of this power panel. If this is true, meade should improve it in the future. Because on the power panel where the screw is used to attach to the mount body, the oil paint on the panel could be easily rubbed away by the screw.
        > > > > > > Hope this experience may be useful for some body else.
        > > > > > > And many thanks to people who helped me!
        > > > > > > :)
        > > > > > >
        > > > > > >
        > > > > > > --- In LX200GPS@yahoogroups.com, John Mahony <jmmahony@> wrote:
        > > > > > > >
        > > > > > > > ----- Original Message ----
        > > > > > > >
        > > > > > > > > From: autostaretx <rseymour@>
        > > > > > > > >
        > > > > > > > > From the symptoms, i would check the cables inside the base
        > > > > > > > > to the RA card.
        > > > > > > > > "Moving by itself" and "not moving at all" happen if the RA motor
        > > > > > > > > card cannot "hear" the main computer card.
        > > > > > > > >
        > > > > > > > > You have to test each wire, end-to-end
        > > > > > > >
        > > > > > > > In an earlier message, he said he had tested the wires with an ohmmeter.
        > > > > > > >
        > > > > > > > -John
        > > > > > > >
        > > > > > > >
        > > > > > > > > Also look for "cold solder joints" or loose pins where the
        > > > > > > > > connectors attach to the circuit cards.
        > > > > > > > >
        > > > > > > > > good luck
        > > > > > > > > --dick
        > > > > > > > >
        > > > > > > > > --- In LX200GPS@yahoogroups.com, "sheng" wrote:
        > > > > > > > > >
        > > > > > > > > > I check the RS232 wire last night, and it's the bad of the wire. After open
        > > > > > > > > the DB9 head, I found one of the wire get broken. After fixing it, I can connect
        > > > > > > > > my computer to it. :)
        > > > > > > > > > But the RA problem is getting more strange. Last night I powered it on, the RA
        > > > > > > > > slewed by itself, it MOVED!!! But I can't control the RA with Autostar. Then I
        > > > > > > > > shut it down and restore the power, RA not move anymore... nor can I control it.
        > > > > > > > > I tried to control it through my computer, but I can only control the DEC. I
        > > > > > > > > tried to directly talking to the telescope with command ":Me#" and ":Mw#",
        > > > > > > > > nothing happen (It worked before). But the telescope has response to the command
        > > > > > > > > ":Mn#" and ":Ms#".
        > > > > > > > > >
        > > > > > > > > > Here is what I think, am I right?
        > > > > > > > > >
        > > > > > > > > > 1. firmware (v 4.2g): not sure.
        > > > > > > > > > 2. Serial input chip: maybe is OK.
        > > > > > > > > > 3. Power panel: seems OK?
        > > > > > > > > > 4. RA motor driver: maybe there's a problem. I didn't see anything burnt...
        > > > > > > > > > 5. Motor encoder: not sure.
        > > > > > > > > > 6. Motor: should be OK.
        > > > > > > > > >
        > > > > > > > > > I will try to flash another firmware to check whether it's a corrupted
        > > > > > > > > firmware issue tonight.
        > > > > > > > > > Thank you!
        > > > > > > > > >
        > > > > > > > > > --- In LX200GPS@yahoogroups.com, John Mahony wrote:
        > > > > > > > > > >
        > > > > > > > > > > Is this scope permanently mounted? Has there been a lightning storm
        > > > > > > > > recently in your area?
        > > > > > > > > > >
        > > > > > > > > > > I'm not sure about the GPS models, but on the old LX200 classic, the
        > > > > > > > > "MAX232" chip in the RS232 electronics was susceptible to lightning damage if
        > > > > > > > > the scope was permanently mounted, and the scope was left attached to an
        > > > > > > > > external computer. That could also explain your RA problem.
        > > > > > > > > > >
        > > > > > > > > > > -John
        > > > > > > > > > >
        > > > > > > > > > >
        > > > > > > > > > >
        > > > > > > > > > >
        > > > > > > > > > > ----- Original Message ----
        > > > > > > > > > > > From: sheng
        > > > > > > > > > > > To: LX200GPS@yahoogroups.com
        > > > > > > > > > > > Sent: Mon, December 28, 2009 11:19:18 AM
        > > > > > > > > > > > Subject: [LX200GPS] Re: My lx200gps is going mad, RA not moving at all...
        > > > > > > > > > > >
        > > > > > > > > > > > Hi John,
        > > > > > > > > > > > Thanks for your reply.
        > > > > > > > > > > > I just upgrade the firmware before this problem coming out. But I didn't
        > > > > > > > > turn on
        > > > > > > > > > > > the "RA PEC ON". The RA/DEC move randomly at their full speed. But right
        > > > > > > > > now, I
        > > > > > > > > > > > can only control the DEC, the RA doesn't move at all.
        > > > > > > > > > > > And I found another problem with it. I can control the telescope with my
        > > > > > > > > > > > computer through RS232 port just after I upgrade its firmware. But today I
        > > > > > > > > just
        > > > > > > > > > > > found I can't control it through the RS232 port anymore...
        > > > > > > > > > > >
        > > > > > > > > > > > --- In LX200GPS@yahoogroups.com, John Mahony wrote:
        > > > > > > > > > > > >
        > > > > > > > > > > > > ----- Original Message ----
        > > > > > > > > > > > >
        > > > > > > > > > > > > > From: sheng da
        > > > > > > > > > > > > >
        > > > > > > > > > > > > > Hi
        > > > > > > > > > > > > > I have a LX200GPS. Recently the telescope seems going mad. At the
        > > > > > > > > beginning,
        > > > > > > > > > > > the
        > > > > > > > > > > > > > RA/DEC randomly move when I power it on.
        > > > > > > > > > > > >
        > > > > > > > > > > > > Can you be more specific? How fast does it move?
        > > > > > > > > > > > >
        > > > > > > > > > > > > The scope usually moves (slowly) in RA when you turn it on. It's
        > > > > > > > > looking for
        > > > > > > > > > > > the PEC sensor. If you didn't used to use PEC, but just recently trained
        > > > > > > > > the
        > > > > > > > > > > > PEC and turned "RA PEC ON", then if it was off before, it wouldn't have
        > > > > > > > > made
        > > > > > > > > > > > that move before, but will now. Or if you recently upgraded from old
        > > > > > > > > firmware,
        > > > > > > > > > > > it moves a lot more than it used to, so maybe you just didn't notice this
        > > > > > > > > > > > before.
        > > > > > > > > > > > >
        > > > > > > > > > > > > -John
        > > > > > > > > > > > >
        > > > > > > > > > > > >
        > > > > > > > > > > > > > And from few days ago, the RA stopped
        > > > > > > > > > > > > > moving totally, but I can control the DEC with my autostar handle.
        > > > > > > > > > > > > > I opened up the base board and checked the wires inside, they seem
        > > > > > > > > fine.
        > > > > > > > > > > > > > Any one know what's going on? Is it possible circuit gets burnt? How
        > > > > > > > > to
        > > > > > > > > > > > examine
        > > > > > > > > > > > > > the source of the problem?
        > > > > > > > > > > > > > Many thanks to you!
        > > > > >
        > > > >
        > > >
        > >
        >
      Your message has been successfully submitted and would be delivered to recipients shortly.