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Old NexStar GPS motor control and hand control firmware update info

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#51 fmav

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Posted 07 July 2019 - 07:11 AM

Are you planning on removing the GPS handset's original flash memory IC and replacing it with SST39SF040, then using the serial port for firmware upgrading?  Even if this proves unsuccessful, as mentioned above, the inability to program via the serial port may not be an issue because it seems unlikely that Celestron will be providing future firmware updates for v4 hand controls. 

 

Please update the thread with your results.

Yes, the 39SF040 (of the newer hc) is pin compatible with the 49F040 (of the original hc).

The Reading protocol of the contents of the memory is the same for the two devices, but erasing/writing is not. The in-circuit programming part (boot block with software for upgrading) of the newer V4 software uses the 39SF040 erasing/writing protocol. The 49F040 gets fully erased with this code, including this boot block, bricking thus the hc.

When I get the parts I will program them with the programmer and then I will check in-circuit programming.

 

The files needed for programming the flash-eproms are the exactly 1Mbyte large bin files provided by Celestron (NXS4.22.bin, NXS 98.22.bin etc). These files have to be split to even and odd (high and low) byte files.

With WinHEX (Menu Tools -> File Tools -> Dissect -> Bytewise) its a simple procedure. WinHex asks for the source file and then outputs two files (the even is the first one). These two files are programmed into the two Flash-eprom chips. After that the chips must be inserted into the sockets on the pcb.


Edited by fmav, 07 July 2019 - 07:30 AM.

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#52 12Bass

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Posted 08 July 2019 - 07:34 AM

Hmmm... I flashed my old GPS handset with the latest v4 firmware and after a few hours of testing inside, v4.22 stopped controlling the scope with a No Response 16 error.  Perhaps this is caused by the same coding issue found in the v5 firmwares?  IIRC, another user here encountered a similar problem with a recent v4 firmware release.  I didn't run the scope very long with the 98.22 firmware, but encountered no such errors while installed.



#53 Michael_Swanson

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Posted 08 July 2019 - 08:25 PM

Hmmm... I flashed my old GPS handset with the latest v4 firmware and after a few hours of testing inside, v4.22 stopped controlling the scope with a No Response 16 error.  Perhaps this is caused by the same coding issue found in the v5 firmwares?  IIRC, another user here encountered a similar problem with a recent v4 firmware release.  I didn't run the scope very long with the 98.22 firmware, but encountered no such errors while installed.

Can you point out the specific post of the other v4 owner with the same problem?  I can't find such a mention.  It might be a hardware issue with the original hand control running the new firmware.  Did it recover from the no response error after a moment or after a reboot?

 

The new v4 firmware was created entirely separate from the v5 firmware so that particular issue didn't cross over.  In fact, the software engineer that produced the v4 firmware has provided the current software engineers with information that should allow them to "fix" this issue in v5.

 

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



#54 12Bass

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Posted 08 July 2019 - 08:59 PM

For anyone interested in flashing a NexStar GPS motor control board (MCB):

 

After the initial firmware flash with a PICkit, my NexStar GPS MCB was non-responsive, presumably due to an issue with the bootloader.  However, once it had firmware 4.06, I was able to perform a normal firmware update via the PC port on the base using a PC port serial programming cable.  This second firmware update rectified the issue, bringing the MCB back to life.  So, having a PC programming cable could come in handy, just in case.... 

 

https://www.nexstars...ammingCable.htm



#55 12Bass

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Posted 08 July 2019 - 10:52 PM

Can you point out the specific post of the other v4 owner with the same problem?  I can't find such a mention.  It might be a hardware issue with the original hand control running the new firmware.  Did it recover from the no response error after a moment or after a reboot?

 

The new v4 firmware was created entirely separate from the v5 firmware so that particular issue didn't cross over.  In fact, the software engineer that produced the v4 firmware has provided the current software engineers with information that should allow them to "fix" this issue in v5.

Sometime in the past few days I thought I had read a post somewhere stating that a newer version of v4 firmware had No Response issues, but am unable to find that specific post at the moment; will post a link if I can find it.  Indoor testing of my GPS mount is continuing using v4.22 with SkySafari via Bluetooth/RS-232 (flashed on original GPS HC).  I reduced the readout rate in SkySafari from 10 to 6 per second and have yet to encounter any errors in the current session.  The scope was able to recover from No Response 16 by pressing Undo... was not a hard lock.

 

Hoping that the original HC software engineer will be able to fix the No Response and sticky button issues in v5.  That would be great news for NexStar GPS owners.



#56 Joe Eiers

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Posted 09 July 2019 - 05:07 AM

Hi!

I recently aquired a nice old 11" GPS model with motor control 1.0 and hand control 1.2.  I used the scope and although I enjoyed using it, I missed a lot of the features I've come to love with my 2013 Nexstar 6SE. One thing the scope didn't do was complete the GPS seach.  I never got a "linked" message.

I read through the Nexstar site and saw that there were some instructions on flashing the chips on the motor control board, but there wasn't enough detail for me to go ahead and give it a shot. I tried reading through here on the process, but couldn't find enough info altogether to make sense to me.

   Can someone hand hold me through the process so I don't end up bricking the chips?  Also would love to hear the input as far as the downside to upgrading.  Is there a way to upgrade the hand control to a more capable unit and still retain the original auto north feature?

    Appreciate anyone's help!

 

  After speaking to Mike, and going through the Yahoo groups forum, there seem to be a number of potential answers.  Sadly, it just makes me more confused.  I hear some people that say you don't even use a PC and upgrade the MC though the HC...  Others say to get the programmers and pull chips and flash...   I'm not unwilling to work hard to do my due diligence, but am afraid I'll mess it all up!!

 

  Mike Swanson suggests I ask here if there might be someone willing to upgrade my chips for me if I send them the board...   Any takers?  I'd be GRATEFUL!, and of course pay.  Must be some kind soul out there....

   Let me know if anyone can help!

 

   Thanks!

      Joe



#57 12Bass

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Posted 09 July 2019 - 08:27 PM

Hi!

I recently aquired a nice old 11" GPS model with motor control 1.0 and hand control 1.2.  I used the scope and although I enjoyed using it, I missed a lot of the features I've come to love with my 2013 Nexstar 6SE. One thing the scope didn't do was complete the GPS seach.  I never got a "linked" message.

I read through the Nexstar site and saw that there were some instructions on flashing the chips on the motor control board, but there wasn't enough detail for me to go ahead and give it a shot. I tried reading through here on the process, but couldn't find enough info altogether to make sense to me.

   Can someone hand hold me through the process so I don't end up bricking the chips?  Also would love to hear the input as far as the downside to upgrading.  Is there a way to upgrade the hand control to a more capable unit and still retain the original auto north feature?

    Appreciate anyone's help!

 

  After speaking to Mike, and going through the Yahoo groups forum, there seem to be a number of potential answers.  Sadly, it just makes me more confused.  I hear some people that say you don't even use a PC and upgrade the MC though the HC...  Others say to get the programmers and pull chips and flash...   I'm not unwilling to work hard to do my due diligence, but am afraid I'll mess it all up!!

 

  Mike Swanson suggests I ask here if there might be someone willing to upgrade my chips for me if I send them the board...   Any takers?  I'd be GRATEFUL!, and of course pay.  Must be some kind soul out there....

   Let me know if anyone can help!

Hi Joe,

 

I'm ab752 from the Yahoo NexStar GPS group.  The firmware update procedures for the hand control (HC) and motor control board (MCB) are different:

 

The original NexStar GPS HC can be updated by removing the two 49F040 chips and flashing them with a programmer like the TL866A using a PLCC32 adapter.  The HC can be flashed with either NexStar GPS firmware 1.6 or 2.2 if you want to keep the original North & Level automatic GPS alignment procedure.  It is also possible to flash old HCs with newer v4 firmware, including 4.22, which has the GPS rollover fix included; however, v4 and later HCs no longer support GPS alignment (due to a lawsuit with Meade), which was replaced with SkyAlign; on newer HCs, Auto Two Star alignment is somewhat similar, though you have to manually slew to the first star. 

 

Also, note that due to hardware changes, an old HC flashed with v4 firmware does not support firmware upgrades via the bottom RS-232 port; in practice, this is probably not an issue because Celestron seems unlikely to provide future firmware updates beyond version 4.22.  Which firmware is preferable depends upon whether you want to keep GPS alignment or if you'd prefer to have the new features available in v4.  Personally, v4 makes the most sense to me because programs like SkySafari no longer support older Celestron HCs, and I like having the new features like Identify. 

 

NexStar GPS MCBs with old firmware (prior to version 3) were not user upgradable and must be updated via in-circuit serial programming (ICSP) either using a programmer like the TL866A or a PICkit, using Andre Paquette's flashing instructions, which are posted here. Once the MCB has firmware version 3 or newer, it is then possible to perform firmware upgrades using Celestron's MCupdate program via either the RS-232 port on the HC or the PC Port on the mount, using a PC programming cable.  Mike Swanson has more detailed info available here.

 

It might seem a tad overwhelming at first, but is really not that difficult to manage if you have the required hardware and go through the steps methodically.  If all this is really too much for you to handle, we can make arrangements for me to perform the firmware update via private messaging.



#58 12Bass

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Posted 05 September 2019 - 05:24 AM

Some photos showing the TL866II Plus configuration required for flashing a NexStar GPS Motor Control board:

 

Load mc1_0406.hex:

Attached Thumbnails

  • Load MC hex.jpg

Edited by 12Bass, 05 September 2019 - 05:41 AM.

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#59 12Bass

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Posted 05 September 2019 - 05:25 AM

Set Configuration Word to 0x3F72:

 

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  • Config Word.jpg

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#60 12Bass

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Posted 05 September 2019 - 05:26 AM

Set all Data to FF except the last byte, which is set to 00:

 

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  • Data.jpg

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#61 12Bass

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Posted 05 September 2019 - 05:26 AM

Program!!! (Note the settings for ICSP, ICSP_VCC Enable)

 

Attached Thumbnails

  • Program.jpg


#62 12Bass

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Posted 05 September 2019 - 05:28 AM

MC Programming Wire Connections:

 

AZM PIC16F876:

 

TL866 ICSP Pin 1: MCLR => MC board J8/PGM Pin 1

TL866 ICSP Pin 2: VCC   => MC board J9/INDEX Pin 1

TL866 ICSP Pin 3: GND   => MC board J9/INDEX Pin 2 or 4

TL866 ICSP Pin 4: PGD   => MC board J8/PGM Pin 3

TL866 ICSP Pin 5: PGC   => MC board J8/PGM Pin 2

 

ALT PIC16F876:

 

TL866 ICSP Pin 1: MCLR => MC board J8/PGM Pin 4

TL866 ICSP Pin 2: VCC   => MC board J9/INDEX Pin 1

TL866 ICSP Pin 3: GND   => MC board J9/INDEX Pin 2 or 4

TL866 ICSP Pin 4: PGD   => MC board J8/PGM Pin 6

TL866 ICSP Pin 5: PGC   => MC board J8/PGM Pin 5

 

I've checked these twice, and they should be correct.  But it would still be a good idea to look at the GPS MC schematic to confirm.  Perhaps I'm being overly cautious... however, I do not want to be responsible for someone else wrecking their precious MC board, so I suggest familiarizing yourself with the wiring diagram and double-checking with a multimeter so that you clearly understand where and why the connections are made as stated.



#63 markb

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Posted 05 September 2019 - 10:19 PM

12Bass, THANKS  for posting the explicit step-by-step MB programming instructions hinted at by many, but never before available at the detail level needed by the otherwise competent non-tech.

 

Particularly the long-needed detailed programming screenshots and specific pin connections with pin numbers! Folks new to PIC programming (including me) really need this level of detail.

 

One possible addition; I believe Andre P. mentioned that a firmware update to 4.06 might initially appear not to have worked, but that following it with a regular MB update would fully enable the MB since the bootloader would now work.  That was the case for me after my solder and replace update of the motor board PIC chips.

 

Since your screenshots of the TL866II settings are more complete than those I used, I have no idea if they eliminate the need for the 'conventional method ' reflash through the PC or hand controller RS232 port. I used the PC port, of it matters.

 

Also note that my very early GPS11 had the 'reversal' extra header cable in the base, and that it was still needed after the update to MB v4.06.

 

Using the INDEX header to apply power from the TL866II os great idea.

 

In the update thread (where this post is partially repeated) you posted a photo of the very early engineering changes/post-prototype board with its soldered on jumper resistors and 4 pin DNSTOP power header.

 

I would appreciate it if you could post pin assignments for the DNSTOP header in this very early board, as the later board only has two pins, and mis-inserting the power header is a real worry on that board. Schematics are for the final board, and do not help on the early board.

 

Geo. had suggested in a PM that my very early PIC chips may have been read/write protected based on my issues in failing to update them, or making any changes at all including attempts to simply erase them.

 

Folks trying to update very early boards might encounter this, so just a caution to the forum that this might occur, although it may only affect a very few bases.

THANKS!


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#64 12Bass

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Posted 07 September 2019 - 07:45 AM

12Bass, THANKS  for posting the explicit step-by-step MB programming instructions hinted at by many, but never before available at the detail level needed by the otherwise competent non-tech.

You're welcome!  Essentially, I've tried to clarify the programming instructions given to me by Andre Paquette, along with some specifics for using the TL866 programmer.

 

The original PIC16F876 Data value given to me by Andre was incorrect, and resulted in non-functional MC board which, thankfully, could then be reprogrammed using the PC port or the HC serial port with MCupdate.  The programming configuration and values posted above should result in a functional NexStar GPS MC board, but may still not be quite correct (as reported by the verify function of MCupdate).  However, once again, reprogramming MC 4.6/4.06 with MCupdate will rectify the issue.  The big hurdle is having to use an external programmer to get past the original non-user-upgradable MC 1.0, 2.0 firmwares.  Once we're able to use MCupdate with a PC, things get much easier as there's no need for an external programmer.  The PC port and HC port should both work equally well.

 

My (~2002) MC board is the final production version, without the AZM crossover cable.  I also updated another early 2001 production MC board with reversed AZM wiring.  However, the flashing procedure was the same for both.  And, yes, the AZM crossover cable was still required when the updated MC board was reinstalled in the owner's NexStar 11 GPS.  Initially, I thought I might have made a mistake, because the azimuth was reversed when I tested the reversed early MC board in my GPS 8 (without the crossover cable), as I was unaware that early units were made this way.

 

IIRC, Andre suggested using the Index/J9 header for powering the board while programming. 

 

I no longer have the early production MC board in my possession.  However, I did use my multimeter to check the traces on the four-pin DNSTOP header and found that the pinout is different.  It looks like the final production boards only have the two middle pins of the four (in the same position, IIRC), and that the early boards have the red wire going to ground instead of power, which seems odd.  Without a schematic for the early MC board, I told the owner of the GPS 11 to take photos before removal and simply plug it back in exactly the same way it came from the factory, operating under the assumption that Celestron knew what they were doing.

 

Not sure about the write protect hypothesis on early MC boards; was not an issue in my case.  My suspicion is that you encountered an incompatibility between HC and MC firmware versions.  IIRC, HC 1.6/2.2 both work fine with MC 4.06, but newer HC firmware does not work with earlier MC firmware.


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#65 Phil_McX

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Posted 19 December 2019 - 09:39 AM

I would like to thank you all for providing the information in this post.

I successfully updated my Nexstar GPS using this thread as a guide coupled with Andre’s schematics.

For everyone elses benefit I used a Pickit 2 with version 2.61 of the pickit programming software. Granted I wasn’t totally sure how to do some settings but I successfully flashed the motor control chips. I had to use celestrons MCupdate afterwards to bring it to working order. All fine and perfect now.

Thank you so much all.


In regards to it not flashing correctly I could use some help for in future,

I managed to set the configuration to 3F42, but thats all. I am unsure of any other steps to take in Pickit 2 to make it a correct flash whereby I don’t need to use MCupdate afterwards. Any tips would be appreciated.

Kind regards, Phil
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#66 12Bass

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Posted 19 December 2019 - 02:11 PM

In regards to it not flashing correctly I could use some help for in future,

I managed to set the configuration to 3F42, but thats all. I am unsure of any other steps to take in Pickit 2 to make it a correct flash whereby I don’t need to use MCupdate afterwards. Any tips would be appreciated.

Hi Phil,

 

You're welcome!  Glad you were able to use this information to update your telescope. 

 

As for PIC programming the MC board without requiring a second flash with MCupdate, I have yet to figure this out myself.  I've updated three different MC boards thus far and all have required the re-flash using a serial cable and MCupdate.  Andre and I had a bit of correspondence about this issue and he told me that 3F72 was the correct configuration word and seemed unsure why it did not program correctly as configured.  The big hurdle is getting the MC board upgraded past the MC 1.0/2.0 firmware so that it can be user updated without a PIC programmer.  I didn't want to bother him further trying to get to the bottom of this knowing that we have a working procedure, even though it does require an extra step and programming cable.
 



#67 Phil_McX

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Posted 19 December 2019 - 02:36 PM

Ahh I wonder where I read 3F42 lol

Yes the main thing is we are able to get it working one way or another.

All of this because of the gps week rollover.. I wouldn’t hve bothered otherwise haha

Anyway, one again thank you. Much appreciated.

Phil.

#68 12Bass

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Posted 19 December 2019 - 02:59 PM

42 is the answer to life, the Universe, and everything!


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#69 jogybaer

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Posted 14 January 2020 - 01:05 PM

@12Bass, thanks for the very good flash instructions of the MC board.
Last weekend I was finally able to flash my 2 C8 mounts with MC 1.2 on MC 4.06.
Everything went great. The tracking can no longer be heard.
The neighbors and my ears are happy.
I also flashed the HC from 1.6 to 2.2. I tested it with 2 x 39SF040 eproms in old HC
It works fine.

Today came 2 x ordered 49f040 eproms. I wanted to test this with NSX4.22; so that I can switch to the GPSfix

 

@fmav: can you please send me the NSX 4.22 as even and odd version

 

Best regards Jürgen

 

 

translated with Google ;-)


Edited by jogybaer, 14 January 2020 - 01:06 PM.

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#70 12Bass

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Posted 14 January 2020 - 08:10 PM

@12Bass, thanks for the very good flash instructions of the MC board.
Last weekend I was finally able to flash my 2 C8 mounts with MC 1.2 on MC 4.06.
Everything went great. The tracking can no longer be heard.
The neighbors and my ears are happy.
I also flashed the HC from 1.6 to 2.2. I tested it with 2 x 39SF040 eproms in old HC
It works fine.

Today came 2 x ordered 49f040 eproms. I wanted to test this with NSX4.22; so that I can switch to the GPSfix

 

@fmav: can you please send me the NSX 4.22 as even and odd version

 

Best regards Jürgen

Hi Jürgen,

 

Glad you were able to use my instructions to update your firmware.  MC4.06 is indeed much quieter than the old NexStar GPS MC firmwares.
 

It is possible to flash your original GPS hand control with NXS4.22 using the original AT49F040 chips.  I'll attach the even and odd .bin files below.

 

Attached File  NXS 4.22_even.zip   288.61KB   23 downloads


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#71 12Bass

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Posted 14 January 2020 - 08:10 PM

Attached File  NXS 4.22_odd.zip   184.03KB   14 downloads


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#72 12Bass

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Posted 14 January 2020 - 11:46 PM

Michael Swanson has graciously hosted the old NexStar GPS Yahoo Group files on Google Drive:

 

https://drive.google...f_-YaqrMispJWvU

 

The GPS firmware and schematics needed for programming can be found in the archive under NexStar GPS > Files > Andre Stuff.


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#73 Alejandro3791

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Posted 22 January 2020 - 10:22 AM

Hi to Alls
I'm a new member in this community .
For start in this I bought an old TASCO STARGUIDE 4 Schmidt Cassegrain telescope with your original hand controller.
I try to use but was impossible to do the autoaligment  and I read in forums that I needed a new hand Controler from Celestron , el NEXSTAR + hand controler with USB conectivity.
I bought the Nextar+ hand controler.
I  connect the Telescope with the new hand controler y run the Celestron actualization program via web , but nothing occurs , in the computer scren i read that the telescope it`s not recognized by the program.
There are anyone that could say if I'm doing anything wrong .

Please give to me a north.......

Kind Regards

Sorry for my poor english .

Victor     from Argentina



#74 Michael_Swanson

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Posted 22 January 2020 - 08:53 PM

Hi Victor,

 

The Tasco StarGuide is NOT compatible with the NexStar+ hand control.  It is compatible with the version 4 hand control if you load the GT 4.04 firmware.  The original hand control may be all you need though it has some minor problems.  On this page of my website:

https://www.nexstars...sGTOriginal.htm

you will find tips that apply to your telescope.  In particular, start with the article "Common Problems with Alignment on the NexStar GT".

 

 

*** If you want to continue this discussion, please start a new topic with the "Start New Topic" button here:

https://www.cloudyni...zed-telescopes/

This particular topic is about a different model of telescope.

 

Best regards,
Mike Swanson
https://www.NexStarSite.com


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#75 Alejandro3791

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Posted 23 January 2020 - 01:49 PM

Hi Mike

 

I really appreciate your answer.
I think that I bought this hand control and was unnecessary.
I was try to read your excellent article  "Odds and Ends
Original NexStar GT and Tasco StarGuide" , but I'm  lost in so many information and I thought that this hand Control would be my salvation......

 

Kind regards

 

Victor




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