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I’m looking for some advice regarding a possible motherboard failure. In the photo of the board in my mount the capacitor circled doesn’t look too good; I believe it has failed. I’m using the mount with a Raspberry pi 3B running Stellarmate. The Pi is powered by the official Rpi power supply and the mount by a 12v power brick with sufficient power for the mount and the peripherals. The mount carries my Skywatcher Explorer 200p and both scope and mount are well balanced. What is happening is the mount will slew easily enough to a target then it will track for a while quite happily, but after a period of time, which varies between a minute and several minutes the reticle on my laptop screen will jump E/W or N/S sometimes by several degrees all the while the mount goes on tracking. Then a N/S jump will take the supposed position below the horizon and the mount will stop tracking. I have also had the mount spontaneously slew to a different position, or creep until the ‘scope is pointing to the ground or worse still, collides with the tripod legs. On occasions it has also been slow to respond. Polar alignment via Stellarmate is near impossible as the software reports 'Mount aborted. Please restart the process and reduce the speed.' If I ignore this I can sometimes get an alignment but not always and reducing the speed does not help. The same thing happens when calibrating the auto-guider, making calibration, on times, impossible. I’ve removed the R-pi and noted the mount also misbehaves when using the Synscan dongle linked to Skysafari. I’ve not had it do a random slew in this configuration but I did not have the scope on the mount at the time. All I saw was the reticle on Skysafari flashing on and off at random intervals. I can leave the mount running with the handset and everything seems fine but the whole idea of using the Rpi was to stay warm whilst photographing the stars and using a robotic telescope on my back yard. It appears the problems are worse when the mount is loaded. I understand from my research the failed capacitor is a smoothing capacitor for the power supply to the board. Is its failure likely to be responsible for odd signals being transmitted to the Rpi which then cause the behaviour in the third paragraph above. Is this the likely source of the problem? Would it be worth simply replacing the failed capacitor in the photo to see if that would help? Or is the board completely Kaput? Any thoughts and advice would be appreciated especially if you have done something like this yourself.

Hi I have a Skywatcher Newtonian telescope ( D:200, f:1000) The other day I noticed that the 'O' ring which was attached to the finder scope had broken. After a bit of digging around, I obtained what I believe is the correct size replacement ( 1.5 mm thickness, 52mm internal diameter). However, I can't see how it attaches to the finder scope ! Can anyone offer some guidance ? Many thanks in advance. Andrew

Due to an unfortunate accident my SN10 primary mirror is broken. While it was an unwieldy beast and pretty much required a complete rebuild when I got it from the previous owner I really loved it. My understanding, thanks to discussions between owners of this OTA, is that the SN10 used a spherical mirror. However Meade's representative did not wish to confirm this "proprietary information" after stating that they could not sell me a replacement. So, I'm stuck with a bit of a quandary: do I roll the dice and attempt to get a spherical mirror constructed? (I doubt that non-parabolic mirrors are routinely manufactured and would probably come at a price-premium). I have read anecdotal discussions that the primaries are somehow "matched" to the schmitt correctors which, I must admit, makes no sense to me as I thought that a spherical mirror was manufactured with a uniform curvature. Thus, without more information, I'm thinking that this could be an expensive and ultimately unworkable solution. Alternatively, do I cut my losses and replace it with something like a Skywatcher 250P? Any other suggestions? Many thanks for taking the time to read this and for any advice you can render.

Hi, Last night when we was out in the night to do astro photographing I got problem with my Star Adventurer mount. The friction coupling in RA axis got stuck and I have difficulties to aim the camera to the object. Today I have dismantled the mount to find what the problem is with it. I got to repair it, I took photos from my disassembling and repair that I think can be interesting for others to look at and read. Here is the link to my homepage: http://www.astrofriend.eu/astronomy/projects/project-star-adventurer-part2-repair/project-star-adventurer-part2-repair.html Have any other of you had a simular problem with the Star Adventurer mount? BR Lars

Good day, I own a skywatcher Heq5 pro mount, its awesome! I just realized the AC wire for my AC / DC adapter is broken (see pic 1). I found another AC wire from an old AC adapter and was wondering if this is ok? I see the gauge wire is bigger though and wonder if it matters? I am thinking of cutting near the female adapter and soldering it back to the entire length of wire that came from the laptop adapter even though the gauge is bigger. ( see pic 2). Thank you.

Repairing a Tal MT3A Mount STEPPER MOTOR Help... Before anyone says "why bother" let me just answer because I'm not ready to pick up a Losmandy at the moment... So I have a Tal 200K which I have enjoyed quite a lot. I have always known that the single motor MT3A mount was less than ideal but it works and if nothing else, an 8" Russian made Kletsov catadioptric scope on a super solid peer mount is a pretty good conversation starter, and some of the views I've seen of Jupiter, especially with a 16mm Nagler - well they were amazing... So a few months ago the mount stopped tracking and slewing at a star party. I could hear that the motor was spinning or making noise, but the mount was definitely not moving under the motor control. I might have just waited and bought something else, but I've had some major expenses plus I'm expecting another due to a large move about to take place so I can't justify spending the money at the moment, BUT I would really like to have a working mount for the Mars opposition in July. So I decided to tear it down and take a good look. I was able to pull the mount casing apart ... and kept going, largely thanks to the PDF AndyH so kindly shared with me that had all the great teardown photos .. despite the native German which apparently translates into comical English with Google Translate ("Loosen the maggot whisk and the grub screws..." is that right??? ) The part that took me some time was realizng after removing the screws holding the case together and removing the setting circles and springs, that it was pretty difficult to unscrew the collar holding the drive shaft in the mount casing. For that I had to use a long screw placed into a hole in the collar as a kind of spoke to get some leverage to unscrew it. Once it started it was easy. Next I was more apprehensive about the drive shaft- The shaft fits through 2 bearings that had not seen freedom in 15 years, so I had to wack the shaft pretty darn hard from one end to break it free. I did this (again thanks to the photo in the pdf) using a block of wood over the end of the sharft - hitting the wood with a small hammer, and then a larger hammer. Like the collar once it was freed up it was easy to slide it through. From there I just took stuff apart until I got into the drive gearbox. The small clock-like gear assembly was not difficult to remove and finally I got a good view of the stepper motor. At first I thought the gear was slipping on the shaft but it winds up being more serious. I removed the gear (loosened the 2 grub screws.. or were the maggot whisks?.. ;-) Of course I kept all the little screws in a secure place and tried to keep them attached to their mating parts when possible. But I think I'll be able to reassemble things.. I don't see any broken gears. My idea is to clean them up and lubricate them with a good quality lithium grease. THE STEPPER MOTOR I hooked up power and the controller and I clearly saw the drive gear is not slipping, but the motor is slipping, - internally. So I need to either repair the motor which no longer has the torque needed to drive the mechanism, or replace it. There's no way I can get the original motor (Tal is out of the astronomy biz and in Russia), and I don't know the specs about the motor to know how to ID it properly with an equivalent. It may be a type NEMA 17 with 6 leads. They aren't that expensive but will it fit? (looks pretty darn similar) Will the gear fit? Does it take the same signals/control voltages? etc. Alternatively Can the motor be repaired? I don't know much about stepper motors so I have non idea.. I know that stepper motors measure steps in degrees, and I imagine there's a spec that specifies the rate of spin, but I' don't know how to find this out for the motor in the MT3S. I have seen a NEMA 17 stepper motor in Amazon and it's less than $20, has 6 leads and has a 1.8 degree step. I might just take a chance and buy the motor and see if I can figure out the wiring.. if it's the same voltage...??... I've attached an image of the printing on the motor and a short video showing it's unfortunate behavior. If anyone has any suggestions how I can move forward I'd really appreciate it. Cheers. Bob TalMT3S-StepperMotor.mp4

As I am hopeless with DIY, give me a car, bike home electrics or plumbing I`m fine anything else I am rubbish. Well bought this ironing chair second hand from Ebay £9.98 came in bubble wrap on inspecting it the back is cracked and broken. For the price I am not bothered about that but could you kind people give me some ideas as to how replace it please.

Hi Guys. I have a NEQ6 Pro mount, about 3 years old. One of those with the poxy little jack on the main circuit-board to plug in the power supply. ( I understand this has been improved in later models) Despite taking care, after much use the inevitable has happened and the socket has parted company from the circuit board and the mount can't be used. Prior to it breaking totally I did a DIY repair soldering it back on to the pcb. This worked for a while but I don't much fancy my chances of doing this a second time, what with hot soldering irons and delicate, heat sensitive electronics not being a great mixture. I live in deepest darkest Shropshire ( Thats in the UK for non locals! ) does anyone out there know of a place within a reasonable distance that they would trust to do the repair. When I contacted Skywatcher, they said I would need to replace the entire pcb and wanted over 200 quid!! This seems just plain silly, it needs someone to attach 2 wires to the pcb going to an external socket, job done and can't break again in the same way. Any suggestions ? I am pinning my hopes on you guys.

Just a quick comment on the service I've received from Steve Collingwood at SCTelescopes. I had a 14" Meade LX200 which had developed a very serious intermittent fault with its electronics. By arrangement, I took the scope to Steve today for him to look at as he is a trained Meade service engineer with many years experience behind him. He offered to work on the scope while I waited since I had a 260 mile round trip and it would potentially save me a second journey to collect the scope. In addition I would provide a second pair of hands as the 14" is a good weight to manhandle. That suited me fine so work began. The electronic faults were investigated and fixed. The scope was then thoroughly cleaned and serviced to a good standard. Normally Steve would accurately collimate the scope before it left the workshop but, as it was going to be bounced around in the back of a car for several hours, we agreed it probably wasn't worth as it would be better done once remounted in the dome. Even so, Steve had a quick check for any obvious misalignment before letting the unit leave. Steve was a very pleasant and knowledgeable chap with a good, traditional approach to and appreciation of quality engineering. The final price was reasonable, the work quality good and, most importantly, the tea was nice! All-in-all a good experience. AndyG