Mini PC crashing caused scope to hit mount

Jon Foulkes · Mar 11, 2026, 01:10 PM

Looking for some help/advice please, on how to understand what caused my mini pc to crash & also how to stop the mount continuing to drive in the event of a pc hanging-up..

Following a recent imaging session I awoke to find my mount (an EQ6-R) had rotated through 180 deg leaving the scope hard up against the pillar mount. The power light on the mini pc (a Mele Quieter 4c) was still on, and the TEC cooling lights on the camera were on, as was the power to the mount (all are mains powered through the supplies that came with the equipment) . My indoor laptop had lost remote connection and wouldn’t re-connect to the mini pc.

After cycling power everything was still working. The last image taken prior to the crash was at 01:19am. The log file from N.I.N.A. shows that the last action was to start an exposure at 01:19:52. The log from PHD2 showed no issues, with the last update occurring at 01:21:44. So everything seemed to be running ok until around 01:21, then simply stopped. I’ve tried checking the Windows11 log files using event viewer, with limited success. The last event recorded was at 01:16, then nothing until I recycled power around 07:15 the following morning. When the mini pc did restart, one of the first events logged at 07:16 showed an error - ‘a previous system shutdown at 01:16 was unexpected’. A further critical event at 07:15 shows system rebooted without cleanly shutting down first - I’m assuming this was as a result of me power cycling the equipment. I’m no expert in win logs, but I suspect there maybe something I’m missing in those logs which might shine a light on what’s happened - would really appreciate any help with this.

My current assumption is that the pc froze, but did not reboot. As the pc stopped responding, then the Meridian Flip didn’t happen (this is set-up via N.I.N.A.). As the mount was tracking at sidereal rate, although there was no further guiding pulses from PHD2 the mount continued to track, which ultimately brought it up against the pillar mount. Although mount limits were set (and enabled) in EQMod, these appear to have had no effect. So my question here - is there some way that the mount limits can be set within the mount which would continue to work even if the pc lost comms?

I have had the same issues in the past (twice I think), fortunately without pier crash. The only thing I could gather that would solve the issue is limit switch that cut the power to the mount in case the RA axis goes physically above a certain angle. Someone on stargazer lounge did a diy on that:

https://stargazerslounge.com/topic/436819-mount-ra-overrun-prevention/#comment-4610601

https://stargazerslounge.com/topic/436714-harmonic-mounts-just-a-bit-too-powerful/page/3/#comment-4610675 (scroll up a bit to find photos of his set up).

Unfortunately I’m shit at diy electronics so I just wake up for meridian flips now, don’t even move out of my bed but I check on my phone that the flip did occur at least. And I wake up to bring back the rig inside quickly after the sequence stopped too.

More advanced mounts have internal limits but not the cheaper models.

Over the years I’ve learned to check for any “Automatic Updates” occurring.

Particularly Windows Security Updates. Because Windows doesn’t like third party App’s on any computer running Windows. They only readily accept App’s from the Windows Store. Which none of our typical equipment apps come from.

So check and see if any Updates have come into your minicomputer lately.

That is the one thing that I’ve found consistent with bad behaviors.

I do hope the crash didn’t bugger up your telescope. Make sure your limits are set correctly, too.

SonnyE · Mar 11, 2026 at 02:10 PM

Over the years I’ve learned to check for any “Automatic Updates” occurring.

Particularly Windows Security Updates. Because Windows doesn’t like third party App’s on any computer running Windows. They only readily accept App’s from the Windows Store. Which none of our typical equipment apps come from.

So check and see if any Updates have come into your minicomputer lately.

That is the one thing that I’ve found consistent with bad behaviors.

I do hope the crash didn’t bugger up your telescope. Make sure your limits are set correctly, too.

I do wonder if a windows update is the cause - there have been several updates since Jan 26 which have caused rdp issues, which ties in to when I started getting this problem. The equipment seems ok, thank God. At the moment I use EQMod for limits (I have proven they work in the past) but need to investigate if anything can be done in the mount itself.

Jon Foulkes · Mar 11, 2026, 02:39 PM

Rick Krejci · Mar 11, 2026 at 02:10 PM

I had a Beelink mini PC that would sometimes reset itself due to the power supply it came with being insufficient. When it would do something computationally intensive (like plate solving/analyzing a new image after download), it would sometimes reboot itself. Once I used my overspeced scope power supply rather than the little brick it came with, all my problems went away.

On the AP mount, you can set it to stop tracking if it loses communication for a certain period of time.

I’d love to know how to stop tracking if it loses comms

For the Astro-Physics mounts using APCC, in the Park tab, there’s a Safety Park feature where you can have it Park to the current position (or any other park position) after a configurable amount of time after losing communication with your PC.

For your mount, it’s not as easy. The last post in this thread seems to indicate a work-around. https://www.cloudynights.com/forums/topic/824870-eq6r-pro-auto-park-on-pc-crash/#findComment-11918131

Rick Krejci · Mar 11, 2026 at 02:55 PM

Jon Foulkes · Mar 11, 2026, 02:39 PM

Rick Krejci · Mar 11, 2026 at 02:10 PM

I had a Beelink mini PC that would sometimes reset itself due to the power supply it came with being insufficient. When it would do something computationally intensive (like plate solving/analyzing a new image after download), it would sometimes reboot itself. Once I used my overspeced scope power supply rather than the little brick it came with, all my problems went away.

On the AP mount, you can set it to stop tracking if it loses communication for a certain period of time.

I’d love to know how to stop tracking if it loses comms

For the Astro-Physics mounts using APCC, in the Park tab, there’s a Safety Park feature where you can have it Park to the current position (or any other park position) after a configurable amount of time after losing communication with your PC.

For your mount, it’s not as easy. The last post in this thread seems to indicate a work-around. https://www.cloudynights.com/forums/topic/824870-eq6r-pro-auto-park-on-pc-crash/#findComment-11918131

Thanks - I’ll look into that 👍

Given the timing, I’d really think windows update got you. You can search ‘update history’ in the windows search and it will give you a log of all previous updates. Per your theory that the PC was frozen, I don’t believe it. You hard reset the PC, and it logged that action. That means it wasn’t frozen up to that time. What I believe is your windows update happened, and it sent you back to the main windows login screen, and some services didn’t start up. RDP being one of them. Don’t ask me why, but this is EXACTLY what happened to me the one time I experienced an update.

Easiest and simplest way to disable automatic updates is to set your network connection to metered. That’s it. No crazy registry changes. Now, keep in mind if for some reason the connection changes, like you get a new router, you’ll have to update that setting again, but I’ve done this now for 2-3 years on all my rigs and only had an issue once, and that was because I created a new wifi, didn’t update metered.

EQMOD mount limits will not work if EQMOD is not on, or frozen.

You can breathe some fresh air in knowing it’s pretty hard to damage an EQ6R in a situation like this. Unless you’re cranking down on the clutches, they allow things to slip. It’s just a brass knob pushing against the smooth brass of the gears, with a bit of grease in the middle. Not the same story for the electronics like the camera, but for this reason I never tighten the clutches more than I need to stop free movement + little bit of wind.

I think the SynScan software allows you to set slew limits on Skywatcher mounts, but you have to do it using the handset. Various sources on the internet claim that this procedure also prevents tracking past the set limit, but I have not tested it.

I believe it can be set in EQMOD as well. Modification using either method is stored in the firmware (like PEC) and is normally respected by software packages.

📷 image.png

Brian Puhl · Mar 11, 2026 at 03:46 PM

Given the timing, I’d really think windows update got you. You can search ‘update history’ in the windows search and it will give you a log of all previous updates. Per your theory that the PC was frozen, I don’t believe it. You hard reset the PC, and it logged that action. That means it wasn’t frozen up to that time. What I believe is your windows update happened, and it sent you back to the main windows login screen, and some services didn’t start up. RDP being one of them. Don’t ask me why, but this is EXACTLY what happened to me the one time I experienced an update.

Easiest and simplest way to disable automatic updates is to set your network connection to metered. That’s it. No crazy registry changes. Now, keep in mind if for some reason the connection changes, like you get a new router, you’ll have to update that setting again, but I’ve done this now for 2-3 years on all my rigs and only had an issue once, and that was because I created a new wifi, didn’t update metered.

EQMOD mount limits will not work if EQMOD is not on, or frozen.

You can breathe some fresh air in knowing it’s pretty hard to damage an EQ6R in a situation like this. Unless you’re cranking down on the clutches, they allow things to slip. It’s just a brass knob pushing against the smooth brass of the gears, with a bit of grease in the middle. Not the same story for the electronics like the camera, but for this reason I never tighten the clutches more than I need to stop free movement + little bit of wind.

I certainly think spurious windows & security updates are unwelcome, particularly given the complex AP software packages & associated drivers we tend to use. It’s why I only allow them during periods between imaging sessions, although I’m sure some still creep in (like windows defender doing stuff). The reason I think the Mele froze is that for about 6 hours there wasn’t anything logged at all - not a single event of any description. It only logged the hard reset after it had powered back up.

Thanks for the tip about setting the network connection to metered - I’ll look into that.

I don’t know what Microsoft’s current policy is, but my own historical experience has been that the usual suggestions for stopping updates work only temporarily. I’ve tried not only the “legit” methods of setting up my internet connection as metered and using Administrator controls, I’ve even deleted the update utility. LIke a bad meal, the updates come back again and again.

Some of the methods Microsoft uses to push these updates on unwilling users includes

1. If you declare your connection metered, it will eventually download the updates anyway or even pull them off another nearby computer using WiFi

2. Microsoft has reached down through the internet to turn updates back on, and to reinstall the update utility. Windows contains a program that reinstalls the update utility if you uninstall it, one that reinstalls the program that reinstalls the update utility, and one that reinstalls the program that reinstalls the program that reinstalls the update utility. I’m not kidding. I’ve done it.

After struggling over a year of having software disabled by updates and clownish events like turning off my computer for an airplane takeoff, only to have windows start installing an update with a warning about the horrible things that will happen if I shut my computer off mid-update, I eventually found that there are various pieces of software available online that will take care of these. Programs like Windows Update Blocker avoid all the aforementioned Microsoft shennangins by simply checking the folder that Microsoft downloads updates into every 5 minutes and deleting any contents. Works great!

For all the folks who want to warn me about security risks: I don’t keep any important personal info on my computer. Over the last 15 years I’ve been seriously inconvenienced by Windows updates many times, buy never by malware. I’m good.

Brian Puhl · Mar 11, 2026, 08:11 PM

Between your comments and Sonny’s about Windows updates being forced on you, I question if something else might be in play here. I’ve never had an issue. I do however, every 6 months to a year go through and let them update. Some of them are important security patches and that I don’t mind. I’ve certainly never had any of them break drivers, uninstall others, or flag the software on my computer which was also echoed above. Something doesn’t seem right and I suspect foul play like a virus or spyware got installed.

No, its a real thing, though I don’t know how common it is these days as I’ve blocked the updates for over a decade now.

The most verifiable example I have comes from work rather than astronomy. I used to use an Excel addin package for my data analysis at work, and virtually every update killed it. The company would scramble to put together a fix, and after a couple of days I’d get an email to download the new software. Then 2 weeks later, Microsoft would break it again. Great software, but I finally gave up on it.

A UPS will sense the loss of mains current but not the loss of data connection between the controller PC and the telescope. It gave me a funny idea though. If you could sense the state of the power light on the mini pc you could use that to turnoff mains current. Pretty easy to do with a photo-sensitive resistor.