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GPS Rollover Problems!

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#1 DanielT

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Posted 07 April 2019 - 10:31 PM

I have a CPC 9.25, purchased in 2006.  The hand controller is new, Next Star Plus and has worked great for two months.  Just yesterday, the GPS link started going haywire.  Yesterday when it linked, it fell to the date 08/21/1999.  Today it shows 08/22/1999. 

 

I can go into utilities and reset the date but the next time it links with GPS the date will be reset to 1999.  The time and location are correctly set by the GPS, its just the date that it gets wrong.  I did the factory reset routine but that did not solve the problem.  In order to align, I have to do so quickly before a new link is established or it will think it is 1999 and not give the proper stars for alignment.  

 

Any help would be greatly appreciated.

 

Thank you.

 

Sincerely,

 

Daniel T.  



#2 evan9162

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Posted 07 April 2019 - 11:09 PM

GPS week number rollover happened yesterday...

 

https://www.labsat.c...=article&id=155


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#3 Michael_Swanson

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Posted 07 April 2019 - 11:26 PM

Hi Daniel,

 

We were worried this would happen.  Celestron's software engineering team was unable to get confirmation from all of the manufacturers for the various GPS receivers they have used through the years so they have been waiting for the rollover to occur so they can implement a fix in the hand control firmware.  I will check back with them.

 

FYI - they have confirmed with their current GPS receiver manufacturer (the one they have been using since 2014) that those receivers are NOT affected by the rollover.

 

In the interim, anyone with an affected mount will probably want to go to the hand control's Utilities menu and turn off GPS.

 

Best regards,
Mike Swanson
Author of "The NexStar Users Guide II"
Author of "The NexStar Users Guide"
Author of "NexStar Observer List"

https://www.nexstarsite.com 


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#4 DanielT

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Posted 08 April 2019 - 04:07 PM

Hello Michael,

 

I appreciate your's and Evan's response. 

 

Do you know if Celestron is planning to ever do a firmware update? 

 

It sounds like there would be a pretty simple code fix.  

 

PS:  I purchased your book a few months ago and now wish I had done so years ago.  I have learned a great deal more on the scope since reading your book and use it as a ready reference.  You really should convince Celestron to include a copy with every new telescope sale.

 

Thank you!

 

Sincerely,

 

 

Daniel T.



#5 Noah4x4

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Posted 08 April 2019 - 06:17 PM

Hello Michael,

 

I appreciate your's and Evan's response. 

 

Do you know if Celestron is planning to ever do a firmware update? 

 

It sounds like there would be a pretty simple code fix.  

 

PS:  I purchased your book a few months ago and now wish I had done so years ago.  I have learned a great deal more on the scope since reading your book and use it as a ready reference.  You really should convince Celestron to include a copy with every new telescope sale.

 

Thank you!

 

Sincerely,

 

 

Daniel T.

My understanding is that regular GPS timeframe is an 'Epoch' comprising of 1024 weeks. Those CN'ers that remember pre-megabyte and Gigabyte days will see the significance of 1024. 

 

The trouble is that different manufacturers of GPS receivers all commenced their Epochs on different dates so despite the common 1024 week parameter, each series will expire on different future dates. Whilst Celestron can confirm that no GPS device manufactured after 2014 would fail on 6th April 2019 as it has that data from the current supplier, it can't confirm when earlier models will fail as previous suppliers have not responded (or are no longer in business).

 

This is a wholly unforseen issue. Manufacturers never expected the lifetime of their devices to exceed 19.7 years and Celestron perhaps didn't understand satellite limitations. If the last digit denoting year generated by the satellite is merely "9", the receiver can't tell if that is 2009, or 2019 or 2029.  However, Celestron should be able to offer a fix on the fly provided it knows the extent of the problem. But with no response from past suppliers, it's only data will be from users as and when devices tangibly fail. I suspect it is an easy fix, but subject to gathering this data. 


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#6 Michael_Swanson

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Posted 08 April 2019 - 07:14 PM

Hello Michael,

 

I appreciate your's and Evan's response. 

 

Do you know if Celestron is planning to ever do a firmware update? 

 

It sounds like there would be a pretty simple code fix.  

 

PS:  I purchased your book a few months ago and now wish I had done so years ago.  I have learned a great deal more on the scope since reading your book and use it as a ready reference.  You really should convince Celestron to include a copy with every new telescope sale.

 

Thank you!

 

Sincerely,

 

 

Daniel T.

Hi Daniel,

 

Thank you for buying the book and for the kind words.  

 

Celestron is indeed working on a firmware update for the hand control (HC) to address this issue.  If one contacts Celestron Tech Support you will receive their official response.  The current plan is that Celestron will create new firmware for the NexStar+ and StarSense HCs, run it through beta testing, and release it to the public in 4 to 6 weeks.  Also, they clarified that the GPS receivers used in their equipment since 2012 (not 2014 as I stated above) are NOT affected.   The current SkySync GPS module is okay, as are the CPCs manufactured since 2012.  We now know the older CPCs are affected.  I'm still verifying if the NexStar 8/9.25/11 GPS series and the older CN-16 GPS module are affected (they probably are).

 

In Celestron's official response, it also states that this will only be fixed via the NexStar+ and StarSense HCs.  Owners with older HCs (version 4 for CPCs manufactured prior to 2012, all of the HCs shipped with NexStar GPS scopes) are advised to:

  • purchase a NexStar+ HC (they are not doing this to sell HCs - it is just that updates of the older HCs are no longer provided due to technical issues)
  • purchase a new GPS module (SkySync is of course the suggested module, though I would recommend the much smaller and slightly cheaper StarGPS-NX - https://www.nexstars.../StarGPS-NX.htm), or
  • turn off GPS in the HC menu and manually enter the date/time.

 

For the older NexStar 8/9.25/11 GPS, many people have foregone use of the newer HCs as they do not offer the automated "North and Level" GPS Align routine.  That routine is only available on HCs version  1.6 and 2.2.  If these mounts are in fact affected by the week rollover and someone wants to use the older 1.6/2.2 HC on one of these scopes, I recommend opening the base, disconnecting the internal GPS and purchasing the StarGPS-NX I linked to above.  It can easily be mounted inside the right fork arm (the one with the HC recess) and then connected to the HC jack in that recess.  Then, use the HC plugged into one of the AUX jacks on top of the base.

 

As soon as all this settles down, I will post an article at my website.

 

Best regards,
Mike Swanson
Author of "The NexStar Users Guide II"
Author of "The NexStar Users Guide"
Author of "NexStar Observer List"
https://www.nexstarsite.com


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#7 mclewis1

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Posted 08 April 2019 - 07:28 PM

This post should be immediately be "stickied" and re posted in a few forums (NexStar, Mounts, and maybe Equipment too). The title of this particular thread isn't clear enough (humorous that it is), any stickied thread should have a clearer title pointing out the failure and Celestron statement.

 

The sooner we get out in front of this mess and post straight forward information the less confused and PO'd folks will be posting in these threads. Leaving it like it is is almost as bad as Celestron's handling of it.


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#8 Michael_Swanson

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Posted 08 April 2019 - 07:34 PM

Update - I've also been chatting with PixSoft about the potential of using the StarGPS-NX as a complete replacement in the NexStar 8/9.25/11 GPS and they reminded me that the compass readings come through the internal GPS module.  The StarGPS-NX does not have a compass (if it did, it would require precise mounting to even make that useful) and simply reports North continuously.  It will definitely be necessary to disconnect the internal GPS or that module will randomly feed bad info to the HC.  So, it may be difficult to keep "north and level" on the older HCs.

 

But, it might still be workable.  The question will be if it still waves left/right looking for north or just sees the StarGPS-NX reporting north and sits still.  The point being as long as the user can manually point north at some point prior to alignment starting, it can still work.

 

If we get this tested and working, I'll let you all know.

 

Note that I'm still verifying whether the NexStar 8/9.25/11 GPS is even affected by the week rollover.

 

Best regards,
Mike Swanson
Author of "The NexStar Users Guide II"
Author of "The NexStar Users Guide"
Author of "NexStar Observer List"
https://www.nexstarsite.com


Edited by Michael_Swanson, 08 April 2019 - 08:34 PM.


#9 Noah4x4

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Posted 09 April 2019 - 02:09 AM

Mike, you are correct that GPS receivers manufactured after 2012 are not affected by the 6th April 2019 Epoch ending rollover date. Thanks for that reassuring update. But am I right in saying they all depend on "Epochs" and hence even later models will be affected by future rollover dates that might fall as soon as 2023 for some? 

 

If so, this means a firmware update for all GPS units will eventually be necessary or they too will 'die'.

 

The fact that each batch might have a different rollover date dependent on release date and this data is possibly unknown means this may be messy. I can't imagine Meade and other manufacturers are immune to this. My guess is nobody ever expected equipment using this technology to survive beyond its originally scheduled 19.7 years and whilst computing technology has advanced from days when everything had to be squeezed into 1024 bytes (1kb), this has remained stuck in some forgotten past paradigm. 

 

I agree with Mark, this thread needs to be pinned especially since all GPS unit owners may ultimate be afftected and a progressive fix rolled out perhaps up to 19.7 years (one Epoch) may be likely. But an Internet source might also replace GPS where a signal is available.  


Edited by Noah4x4, 09 April 2019 - 02:10 AM.


#10 rnshagam

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Posted 09 April 2019 - 11:18 AM

My old iOptron GPS module is now reporting 8/24/2099.  I don't suppose there will be a fix from them!!!



#11 Michael_Swanson

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Posted 09 April 2019 - 05:34 PM

Mike, you are correct that GPS receivers manufactured after 2012 are not affected by the 6th April 2019 Epoch ending rollover date. Thanks for that reassuring update. But am I right in saying they all depend on "Epochs" and hence even later models will be affected by future rollover dates that might fall as soon as 2023 for some? 

 

If so, this means a firmware update for all GPS units will eventually be necessary or they too will 'die'.

 

The fact that each batch might have a different rollover date dependent on release date and this data is possibly unknown means this may be messy. I can't imagine Meade and other manufacturers are immune to this. My guess is nobody ever expected equipment using this technology to survive beyond its originally scheduled 19.7 years and whilst computing technology has advanced from days when everything had to be squeezed into 1024 bytes (1kb), this has remained stuck in some forgotten past paradigm. 

 

I agree with Mark, this thread needs to be pinned especially since all GPS unit owners may ultimate be afftected and a progressive fix rolled out perhaps up to 19.7 years (one Epoch) may be likely. But an Internet source might also replace GPS where a signal is available.  

Yes, that is exactly the implications of the various methods a GPS receiver (not Celestron's design but a receiver they implement in their products) might employ to deal with the 1024 week recurring rollover.  There are basically three ways a GPS receiver can deal with the week rollover:

1) It stores a static date (usually the date of the receiver's firmware creation) and if the date it calculates after GPS sync is earlier than the static date, it adds 1024 weeks.  This means that the receiver is okay on Apr 7, 2019, but will start calculating the incorrect date at some point in the future (1024 weeks after the firmware date).  This is the scenario you are considering Noah.
2) After a GPS sync, it compares the new calculated date to the last date it had stored in its temporary memory.  If the new date is earlier than the last stored date, it adds 1024 weeks.  The problem with this is that the temporary memory is dependent upon the backup battery (or super capacitor in the newer CPC mounts and SkySync module) in the receiver.  As most NexStar GPS owners are aware, those batteries do not last forever and can also be completely discharged (https://www.nexstars...es/GPSBoard.htm).  In this scenario, if the battery/super capacitor discharges and the last date/time is lost, it will likely resort to a variation of option 1 meaning it will eventually calculate an incorrect date.
3) This one is a variation of option 2, with the difference being that the last date/time is stored in non-volatile memory - semi-permanent memory that doesn't require a battery/capacitor to keep its stored values.  This one is obviously the best as it can keep working indefinitely, but we (and Celestron to my knowledge) have no idea if any of the GPS modules used in their scopes employ this method.

 

So, all that said, Celestron's HAND CONTROL firmware will be aware of this issue going forward (NexStar+ and StarSense HCs only) and easily be able to deal with it.  Why?  Because the HC will check the date being provided by the GPS module and if that date is earlier than the date of the HC firmware, it will add 1024 weeks.  If it is still earlier, it will add another 1024 (in iterations) until it is a date later than the firmware date.

 

Best regards,

Mike Swanson
Author of "The NexStar Users Guide II"
Author of "The NexStar Users Guide"
Author of "NexStar Observer List"
https://www.nexstarsite.com


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#12 DanielT

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Posted 09 April 2019 - 10:56 PM

Here is the official response I received from Celestron:

 

 

Dear Daniel,

 

Thank you for contacting Celestron Technical Services. Since you purchased your unit before 2012 you will more than likely have to use one of the below options to use your scope.

1. Purchase a NexStar+ hand control (SKU 93981 for AZ or SKU 93982 for EQ) and update its firmware using CFM (***note the firmware is in the works but we do not have a date when it will be available yet).
2. Purchase a SkySync GPS Accessory. (SKU 93969) This replaces the GPS receiver module in your existing product.
3. Do nothing, and correct the date manually in the hand control before aligning the telescope.
If you are unsure if you have the NexStar+ or the older NexStar hand control, you can look at the NexStar logo printed on the LCD screen window. If the NexStar logo has a “+” after it, then it is the NexStar + hand control. If the NexStar logo has a “*” after it, then it is the older NexStar hand control.

Thank you

 

Elena

 

Technical Services Representative

2835 Columbia Street | Torrance, CA 90503 | www.celestron.com
, Celestron Technical Support



#13 Michael_Swanson

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Posted 09 April 2019 - 11:04 PM

A couple of caveats about the response from Celestron Tech Support (caveats which I have already fed back to Celestron):

 

For option 2, if you purchase a replacement external GPS module (like the SkySync or PixSoft's StarGPS-NX), you will need to open up the mount and disconnect the internal GPS module.  Otherwise, it will be hit and miss as to which module feeds the date/time/location to the hand control.

 

For option 3, you would need to go to Utilities in the hand control menu and turn off GPS the hand control might switch to the GPS date/time even after you manually enter a good date.

 

It is also important to remember that Daniel has a version 4 hand control and Celestron currently faces significant technical issues (perhaps insurmountable) in providing a fix on those HCs.  That is why the response said in option 1 that it might be necessary for Daniel to purchase a NexStar+ HC.

 

Also, I have been asked outside of this forum whether the upcoming firmware fix will work on the older, RJ-22 (phone jack vice USB) version of the NexStar+ and StarSense HCs - yes, it will.

 

Best regards,
Mike Swanson
Author of "The NexStar Users Guide II"
Author of "The NexStar Users Guide"
Author of "NexStar Observer List"
https://www.nexstarsite.com



#14 Digital Don

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Posted 10 April 2019 - 12:04 AM

I would like to thank Mike Swanson for all his assistance and insight into this issue.

 

One of my scopes (an affected CPC 1100) is permanently mounted (Alt-Az) in my observatory.  I discovered the GPS issue last night.  Since my scope is always in the same location, I use the 'hibernate' feature at the end of an observing session so I don't have to align next time.  I'm definitely spoiled by not having to realign each observing session!

 

After reading through this thread, I decided to turn the GPS off before putting the scope to sleep.  Upon waking the scope with GPS off, it now asks for the time and date which I entered manually  and sent the scope to Arcturus.  It was nearly centered in a cross-hair eyepiece (about the same accuracy as I typically get).  However, the scope was in hibernation less than 24 hours so I don't know how significant that result actually is.

 

It's going to be cloudy for the next few days, so I won't be able to check it until it clears again.  But if all that's required (for a permanently mounted scope) is turning the GPS off and manually enter the time and date, I can live with that. 

 

Of course my portable CPC 800 of similar vintage is a different matter...

 

Don usa.gif

 



#15 emflocater

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Posted 10 April 2019 - 09:53 AM

Thank you Mike Swanson for the updates from Celestron. It bums me out that having the version 4 hand control and the CN-16 GPS Unit, that IF Celestron is able to create a Firmware that one will need to purchase a NexStar+ for the CN-16 to work. So bottom line is...purchase a new compatible GPS or a new NexStar+ or plug in your values manually !

 

It is my understanding that the NexStar+ hand control will either not work with the CG5-ASGT Mount and or not firmware update the Motor Control board and if tried can Brick your mount. What a mess!

 

I wish Celestron would offer a swap or at lease a huge discount if one has to go from the version 4 to the NexStar+ hand control as its not the consumers fault that they took care of their equipment to last so long and Celestron did not figure the Rollover with their GPS Units. As long as one can show a receipt of proof of purchase of version 4 hand control and return it for the NexStar+ would in my mind be fair game.

 

Do all the NexStar+ hand controls connect via USB now? If so what change in cables and other issues can I expect going from the NexStar version 4 to the NexStar+?

 

Maybe there is an computer electronic wizard among us out there that can add a code/firmware or something that would allow the version 4 hand control to work with the CN-16 GPS and forward it to Celestron.

 

Either way, other than doing it manually, it will cost all those and myself in this similar situation money to correct something of no fault we did. Also please don't advise me that I can get an App and run a GPS via some type of

I-Phone or Smart phone etc. I have a simple pay as you go phone for emergencies and still use a LAN line. I have already spent enough money on this hobby over the years. Man I am bummed! bangbang.gif

 

Cheers

Don


Edited by emflocater, 10 April 2019 - 10:04 AM.


#16 hobbes

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Posted 10 April 2019 - 04:07 PM

I couldn't be happier to see users discussing this issue, it sheds a lot of light of the current GPS rollover problem. I also contacted Celestron by phone and received the same response. It sounds like the quick fix is to: Purchase a SkySync GPS Accessory. (SKU 93969) This replaces the GPS receiver module in your existing product.

 

Since I am not looking at waiting 4-6 weeks for a HC firmware update, and buying the NexStar+ HC, I was hoping to possibly pick up the SkySync GPS accessory and continue on my way. However, reading Michael's response, "you will need to open up the mount and disconnect the internal GPS module.", I am a bit wary of opening up the mount. The Celestron technical support representative mentioned that I didn't need to open the mount, and am now conflicted and wonder if this is the route I want to go. Shouldn't the SkySync GPS accessory bypass the internal GPS receiver module? If not, can you refer me to any documentation on how I could manually disconnect the internal GPS receiver?

 

I took a look at the StarGPS receiver as well, and the 65 channel receiver seems like a great update over the 16 channel receiver from SkySync, at a much better price. Micheal, you mentioned that the StarGPS receiver does not have a built in compass, any idea if the SkySync does? When I set up my wedge to do my polar alignment, I am always facing the wedge so it points North. I was hoping you could clarify what you meant by pointing North to resolve the non-compass issue?

 

If I purchase the SkySync or StarGPS accessory, wouldn't it also have an Epoch that is set to rollover in the future. If that's the case, is it possible to update the SkySync or StarGPS firmware for future updates?


Edited by hobbes, 10 April 2019 - 04:47 PM.


#17 Michael_Swanson

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Posted 10 April 2019 - 06:05 PM

Thank you Mike Swanson for the updates from Celestron. It bums me out that having the version 4 hand control and the CN-16 GPS Unit, that IF Celestron is able to create a Firmware that one will need to purchase a NexStar+ for the CN-16 to work. So bottom line is...purchase a new compatible GPS or a new NexStar+ or plug in your values manually !

 

It is my understanding that the NexStar+ hand control will either not work with the CG5-ASGT Mount and or not firmware update the Motor Control board and if tried can Brick your mount. What a mess!

 

I wish Celestron would offer a swap or at lease a huge discount if one has to go from the version 4 to the NexStar+ hand control as its not the consumers fault that they took care of their equipment to last so long and Celestron did not figure the Rollover with their GPS Units. As long as one can show a receipt of proof of purchase of version 4 hand control and return it for the NexStar+ would in my mind be fair game.

 

Do all the NexStar+ hand controls connect via USB now? If so what change in cables and other issues can I expect going from the NexStar version 4 to the NexStar+?

 

Maybe there is an computer electronic wizard among us out there that can add a code/firmware or something that would allow the version 4 hand control to work with the CN-16 GPS and forward it to Celestron.

 

Either way, other than doing it manually, it will cost all those and myself in this similar situation money to correct something of no fault we did. Also please don't advise me that I can get an App and run a GPS via some type of

I-Phone or Smart phone etc. I have a simple pay as you go phone for emergencies and still use a LAN line. I have already spent enough money on this hobby over the years. Man I am bummed! bangbang.gif

 

Cheers

Don

Regarding the NexStar+ and the AS-GT mount - it works fine with that mount, the only caveat is you cannot update the motor control firmware through that hand control.   The AS-GT mount hasn't received a firmware update in many, many years (current version is 5.20) and isn't likely to ever see another so this really isn't that big of an issue.

 

Yes, all current NexStar+ HCs have the USB port on the bottom.  That connects to an internal USB serial port adapter which requires a driver be loaded on the external computer.  More details on this and the required cable on this page of my website:

https://www.nexstars...m/PCControl.htm

 

It is definitely frustrating, but quite similar to all other technology.  For example, though my first smartphone is still running fine (I use it to stream music to my home stereo), it is no longer secure and runs a version of Android that is not compatible with a lot of the apps I like to use.

 

Regarding Celestron finding a path forward to provide the required update in the version 4 HC - I would suggest that for everyone that has the GPS issue and also a version 4 HC; log a ticket with Celestron Tech Support stating you really want the fix on the version 4 HC.  If management doesn't see this as an issue important enough to expend the (substantial) extra time and effort (which equals money) to overcome the issues they are facing, they won't expend that money.

 

Regarding the SkySync or StarGPS accessories and potential future rollover problems - yes, it would be possible to update their built-in firmware in the future.  But there are caveats to this.  Celestron has not provided a firmware update for any of their GPS modules to date and I think they will continue to lean on the more universal fix of managing it in the HC.  PixSoft is right now providing updates for their first generation GPS modules which are affected by the current rollover, but they are a small, privately-owned venture so there is no certainty they will be around for the next rollover.

 

Bottom line, technology becomes obsolete...

 

Best regards,
Mike Swanson
Author of "The NexStar Users Guide II"
Author of "The NexStar Users Guide"
Author of "NexStar Observer List"
https://www.nexstarsite.com



#18 Michael_Swanson

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Posted 10 April 2019 - 06:16 PM

I couldn't be happier to see users discussing this issue, it sheds a lot of light of the current GPS rollover problem. I also contacted Celestron by phone and received the same response. It sounds like the quick fix is to: Purchase a SkySync GPS Accessory. (SKU 93969) This replaces the GPS receiver module in your existing product.

 

Since I am not looking at waiting 4-6 weeks for a HC firmware update, and buying the NexStar+ HC, I was hoping to possibly pick up the SkySync GPS accessory and continue on my way. However, reading Michael's response, "you will need to open up the mount and disconnect the internal GPS module.", I am a bit wary of opening up the mount. The Celestron technical support representative mentioned that I didn't need to open the mount, and am now conflicted and wonder if this is the route I want to go. Shouldn't the SkySync GPS accessory bypass the internal GPS receiver module? If not, can you refer me to any documentation on how I could manually disconnect the internal GPS receiver?

 

I took a look at the StarGPS receiver as well, and the 65 channel receiver seems like a great update over the 16 channel receiver from SkySync, at a much better price. Micheal, you mentioned that the StarGPS receiver does not have a built in compass, any idea if the SkySync does? When I set up my wedge to do my polar alignment, I am always facing the wedge so it points North. I was hoping you could clarify what you meant by pointing North to resolve the non-compass issue?

 

If I purchase the SkySync or StarGPS accessory, wouldn't it also have an Epoch that is set to rollover in the future. If that's the case, is it possible to update the SkySync or StarGPS firmware for future updates?

You will most definitely need to disconnect the internal GPS receiver to get consistent results.  Otherwise you have two devices with the same internal address responding to the hand control's request for GPS data.  I don't have any pictures of the locations of the connections of the internal GPS receiver but perhaps someone will jump in.

 

The CPC does not have an internal compass, that is only an issue for the owners of the NexStar 8/9.25/11 GPS scopes.  They had an alignment routine (used only in alt-az mode) where the scope automatically pointed north and level and then moved off to the first alignment star with no user intervention.  This depends upon a functioning internal GPS module (the compass interfaces with the rest of the system through that module) and we are trying to work out a method where the internal GPS could be disconnected and a replacement like the StarGPS-NX is used in its place.  But, since all owners we of NexStar 8/9.25/11 GPS scopes have reported no rollover problems, this is likely a moot point (for now).

 

See my previous post regarding potential rollover problems in the future.

 

My recommendation for your scenario is just to turn off GPS in the hand control for now and manually enter date/time until you see a clear path forward that works for your situation.

 

Best regards,
Mike Swanson
Author of "The NexStar Users Guide II"
Author of "The NexStar Users Guide"
Author of "NexStar Observer List"
https://www.nexstarsite.com


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#19 emflocater

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Posted 10 April 2019 - 07:12 PM

Hi Mike Swanson. I had spoken to Celestron this morning and can confirm everything you have posted to us. Again thank you. As you stated and so did Celestron, they are working on a firmware update to allow the Celestron GPS's affected by the rollover to work. They mentioned this firmware would be with the NexStar+. What I don't get is since I have a version 4 hand control and after doing some research...its been stated that there is only a slight difference between version 4 and NexStar+. I don't see why Celestron can't create a firmware that works on both hand controllers. It would seem to me that just as many if not more Folks are still using the version 4 hand control than the NexStar+. Thoughts?

 

Cheers

Don



#20 Michael_Swanson

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Posted 10 April 2019 - 08:07 PM

I'm not at liberty to discuss the details of the challenges Celestron is facing in updating firmware on the NexStar version 4 HCs, but I can tell you that one of the primary reasons Celestron created the NexStar+ HC is that they had pushed the version 4 hardware to its limits.  The NexStar+ HC has a faster processor and more memory which allowed Celestron to continue to develop new capabilities and features that are not possible on the v4 HC.

 

You are correct that the majority of the individuals experiencing this problem have the v4 HC.  Here is the timeline of some key hardware (not exhaustive of all possible Celestron GPS gear):

  • NexStar 11 GPS and NexStar 8 GPS:  models shipped between fall 2001 and 2002 have Celestron's original GPS module - two piggybacked boards.  But, at some time in 2002 or early 2003 Celestron switched to a newer second generation GPS module with a single circuit board.  All NexStar 9.25 GPS have the second generation.  We have heard from a few N8GPS owners and one N11GPS owner that their scopes are displaying the correct date after the rollover, but we are still trying to determine which of the two GPS modules each has.
  • CN-16 - this external GPS module has the same second generation GPS board as the later NexStar GPS scopes.  (Don - are you stating that you have confirmed the CN-16 is affected by the rollover?)
  • The version 4 hand control was released in early 2005.
  • CPC series:  This series replaced the NexStar GPS scopes in 2005 and shipped with the version 4 HC until the NexStar+ HC was released in 2012.  The models shipped from 2005 through 2012 are confirmed to have a problem with the rollover.  It is uncertain if they used the same GPS module as the CN-16 and later NexStar GPS scopes, or a different third model.  A new GPS module was incorporated in 2012 which is confirmed to NOT have a problem with the rollover.
  • CPC Deluxe:  This model was introduced in 2012 and always used the newest, unaffected GPS module.
  • SkySync: I don't know the actual date it was released, but it was around 2012 and it uses the newest, unaffected GPS module.
  • The NexStar+ hand control was released in early 2012.

So...the v4 HC was in use during the entire time the CPC series included the affected GPS module. I haven't kept up with release dates on the GEM mounts, but I do know the AS-GT and the CGEM and CGE Pro shipped with the v4 HC from 2005 onward and of course the GEM mounts switched to the NexStar+ HC in 2012.

 

Best regards,
Mike Swanson
Author of "The NexStar Users Guide II"
Author of "The NexStar Users Guide"
Author of "NexStar Observer List"
https://www.nexstarsite.com


Edited by Michael_Swanson, 10 April 2019 - 08:47 PM.

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#21 emflocater

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Posted 10 April 2019 - 08:44 PM

I'm not at liberty to discuss the details of the challenges Celestron is facing in updating firmware on the NexStar version 4 HCs, but I can tell you that one of the primary reasons Celestron created the NexStar+ HC is that they had pushed to the version 4 hardware to its limits.  The NexStar+ HC has a faster processor and more memory which allowed Celestron to continue to develop new capabilities and features that are not possible on the v4 HC.

 

You are correct that the majority of the individuals experiencing this problem have the v4 HC.  Here is the timeline of some key hardware (not exhaustive of all possible Celestron GPS gear):

  • NexStar 11 GPS and NexStar 8 GPS:  models shipped between fall 2001 and 2002 have Celestron's original GPS module - two piggybacked boards.  But, at some time in 2002 or early 2003 Celestron switched to a newer second generation GPS module with a single circuit board.  All NexStar 9.25 GPS have the second generation.  We have heard from a few N8GPS owners and one N11GPS owner that their scopes are displaying the correct date after the rollover, but we are still trying to determine which of the two GPS modules each has.
  • CN-16 - this external GPS module has the same second generation GPS board as the later NexStar GPS scopes.  (Don - are you stating that you have confirmed the CN-16 is affected by the rollover?)
  • The version 4 hand control was released in early 2005.
  • CPC series:  This series replaced the NexStar GPS scopes in 2005 and shipped with the version 4 HC until the NexStar+ HC was released in 2012.  The models shipped from 2005 through 2012 are confirmed to have a problem with the rollover.  It is uncertain if they used the same GPS module as the CN-16 and later NexStar GPS scopes, or a different third model.  A new GPS module was incorporated in 2012 which is confirmed to NOT have a problem with the rollover.
  • CPC Deluxe:  This model was introduced in 2012 and always used the newest, unaffected GPS module.
  • SkySync: I don't know the actual date it was released, but it was around 2012 and it uses the newest, unaffected GPS module.
  • The NexStar+ hand control was released in early 2012.

So...the v4 HC was in use during the entire time the CPC series included the affected GPS module. I haven't kept up with release dates on the GEM mounts, but I do know the AS-GT and the CGEM and CGE Pro shipped with the v4 HC from 2005 onward and of course the GEM mounts switched to the NexStar+ HC in 2012.

 

Best regards,
Mike Swanson
Author of "The NexStar Users Guide II"
Author of "The NexStar Users Guide"
Author of "NexStar Observer List"
https://www.nexstarsite.com

 

CN-16 - this external GPS module has the same second generation GPS board as the later NexStar GPS scopes.  (Don - are you stating that you have confirmed the CN-16 is affected by the rollover?)

 

Yes Mike I am confirming that my CN-16 has been affected by the Rollover. I have been using the CN-16 on my CG5-ASGT and Version 4 Hand controller for years with no issues. My Version 4 has HC 4.21 and MC 5.20 so its fully updated.

 

If Celestron does get a firmware that will allow the CN-16 to work via the NexStar+ hand controller, would my CG5-ASGT Mount be able to use the NexStar+ hand controller?

 

Cheers

Don



#22 Michael_Swanson

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Posted 10 April 2019 - 08:50 PM

 

If Celestron does get a firmware that will allow the CN-16 to work via the NexStar+ hand controller, would my CG5-ASGT Mount be able to use the NexStar+ hand controller?

 

Cheers

Don

Yep, from my post above: "Regarding the NexStar+ and the AS-GT mount - it works fine with that mount, the only caveat is you cannot update the motor control firmware through that hand control."

 

And Celestron will definitely update the NexStar+ firmware to fix the date coming from the CN-16.  Note that I am presuming you are seeing a date of August 1999 after it links - if you are seeing something else, we need to dig deeper.

 

Best regards,
Mike Swanson
Author of "The NexStar Users Guide II"
Author of "The NexStar Users Guide"
Author of "NexStar Observer List"
https://www.nexstarsite.com


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#23 Digital Don

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Posted 10 April 2019 - 09:19 PM

I thought I would do a little sleuthing on this issue while waiting for it to clear - which could be a long wait in this part of the county... 

 

I put on my deerstalker hat and deduced the following using my version 4 hand control equipped portable CPC 800 and permanently mounted CPC 1100...

 

I woke my observatory scope and allowed the GPS to link.  Checking the results, I found that the time and location were correct, but the date was wrong.  I went to the SCOPE SETUP menu and selected SETUP TIME-SITE.  In this menu you can edit the values for time, date, location, time zone, etc.  I corrected  the date and exited the menu. 

 

I use SkySafari to control my scopes.  When I initially discovered the GPS issue, connecting to SkySafari indicated that the scope was pointing to about 40° below the horizon!  Tonight, SkySafari showed that the scope was pointing to the proper position in the sky.  Since it's cloudy, I couldn't actually test by doing a GOTO, but based on what I saw, I'm guessing it will work properly.

 

I also discovered that if you enter VIEW TIME-SITE in the menu, the date reverts to the incorrect value even after correcting it in the SETUP TIME-SITE menu!

 

Since I wasn't sure if the latitude and longitude values were obtained from tonight's GPS link or retained from the last session, I decided to check my CPC 800 which was last used about 200 miles away.  After the GPS linked, my current latitude and longitude were displayed along with the correct time.  Again, the date was incorrect.  I corrected the date as above and everything seemed fine.

 

I may purchase a Nexstar+ HC just to have the ability to obtain future updates, but  I'm hoping all that's absolutely necessary to resolve this issue is entering the correct date!

 

Don usa.gif

 

 

 

 



#24 Michael_Swanson

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Posted 11 April 2019 - 12:41 AM

Don,

 

Your discovery about how View Time-Site re-queries the GPS and again sets the incorrect date is why I advised:

- you would need to go to Utilities in the hand control menu and turn off GPS otherwise the hand control might switch to the GPS date/time even after you manually enter a good date.

 

Besides View Time-Site, there are other times when it would happen and catch you off guard, most notably, if you start through the alignment process, manually fix the time, then back your way out and restart alignment.

 

The disadvantage of turning off GPS in Utilities menu is that you would also need to manually enter the time.  And if you travel with your scope a lot, it does as Don notes store the last long/lat and won't update automatically.

 

So, pick your poison :-)

 

Best regards,
Mike Swanson
Author of "The NexStar Users Guide II"
Author of "The NexStar Users Guide"
Author of "NexStar Observer List"
https://www.nexstarsite.com


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#25 emflocater

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Posted 11 April 2019 - 10:33 AM

Don,

 

Your discovery about how View Time-Site re-queries the GPS and again sets the incorrect date is why I advised:

- you would need to go to Utilities in the hand control menu and turn off GPS otherwise the hand control might switch to the GPS date/time even after you manually enter a good date.

 

Besides View Time-Site, there are other times when it would happen and catch you off guard, most notably, if you start through the alignment process, manually fix the time, then back your way out and restart alignment.

 

The disadvantage of turning off GPS in Utilities menu is that you would also need to manually enter the time.  And if you travel with your scope a lot, it does as Don notes store the last long/lat and won't update automatically.

 

So, pick your poison :-)

 

Best regards,
Mike Swanson
Author of "The NexStar Users Guide II"
Author of "The NexStar Users Guide"
Author of "NexStar Observer List"
https://www.nexstarsite.com

Mike would it be possible to do this as I guess I should try it before I ask (stupid me) anyways... I could keep the CN-16 Connected as normal until it connects and loads the time, date, longitude/latitude into the mount/hand control. Then once that is done go into Utilities and then shut off the GPS. Then I can go back and simply change ONLY the date in the hand control and I should be set for the evening session. 

 

Seems the GPS does everything right except the date and I thought this might be a work around until Celestron can address the issue permanently.

 

Cheers

Don


Edited by emflocater, 11 April 2019 - 10:35 AM.



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