Date   

GTO control system questions

sdheckenlively
 

Hi,

Does the GTO control system provide magnetic damping of the declination axis by powering the motors? If not, would this be a feasible enhancement some day?

Also, can the Pulseguide built into the controller be run at the same time as autoguiding? What would be the approximate drift per second necessary for Pulseguide to keep the declination motor continuously energized? (Or as at least as energized as the right ascension is.)

Note my understanding is that the builtin Pulseguide operates much faster than 1Hz (how fast?), to the point that it is "proactive," not "reactive." True?

I'm asking because of a recent battle with wind. My near term remedy was to order a 24" pier (16" post). But the above might be helpful for general autoguiding.

Thanks,
Steve


Re: GTO control system questions

Roland Christen
 

In a message dated 10/20/2009 8:14:24 PM Central Daylight Time,
sdheckenlively@... writes:


Does the GTO control system provide magnetic damping of the declination
axis by powering the motors? If not, would this be a feasible enhancement
some day?
If you are asking this as a remedy for wind loading, the answer is no. The
motor would have zero effect on wind loading. Our mounts are operated thru a
worm gear. One cannot run a worm gear backwards (unless the worm wheel has
only a few teeth). Therefore, the wind cannot turn the worm backwards or
forwards, because it is opposed by the gear teeth of the driving worm gear. The
worm itself acts as a brake.

What is causing any kind of movement when the wind blows is the deflection
of the mount and pier assembly, as well as deflection in the end bearings of
the worm gear. Whenevere there is a load on eaither axis, the worm is
driven sideways against the end bearings, and the resultant torque is transmitted
to the mount base and into the pier. The motors are out of the equation at
that point. They have no function whatsoever in countering this end loading.


DSV Beta 3 file install order?

Gary
 

I find myself needing to reinstall my old Beta 3 version of Digital Sky Voice and have forgotten (and can't find) the instructions that direct the order in which the files need to be installed.
I'm hoping some kind sole can 'remind' me of the proper order in which to install them.

TIA, and best regards,

Gary


Re: Latest images from Toa Observatory

toa.mm@libero.it <toa.mm@...>
 

Sorry for the message structure... I try a reply:Hi group,These images that I want to share with you all, are always the latest exciting images I've done. I hope that you like it!!The image is taken with Achromatic 152/900 Telescope Service and great Apogee Alta U9 on the granitic Astrophysics 1200 GTO. Details are in image.All new images are labeled with a bright "NEW"If you want visit my website please link to:http://www.skytoa.it/ For looking Luminance please visit this link:http://www.skytoa.it/galleria_nebulose_halfa.html For looking a Colour please visit this link:http://www.skytoa.it/galleria_nebulose.htmlAny comments are welcome!Thanks a lot for looking,Matteo Morino T.O.A. Torrazzo Osservatorio Astronomicodi Matteo Morinowww.skytoa.ittoa@...







----Messaggio originale----Da: toa.mm@...: 19/10/2009 22.08A: <ap-gto@...>Ogg: [ap-gto] Latest images from Toa Observatory


----Messaggio originale----Da: toa.mm@...: 19/10/2009 22.08A: <ap-gto@...>Ogg: [ap-gto] Latest images from Toa Observatory


----Messaggio originale----Da: toa.mm@...: 19/10/2009 22.08A: <ap-gto@...>Ogg: [ap-gto] Latest images from Toa Observatory


----Messaggio originale----Da: toa.mm@...: 19/10/2009 22.08A: <ap-gto@...>Ogg: [ap-gto] Latest images from Toa Observatory





Hi group,These images that I want to share with you all, are always the latest exciting images I've done. I hope that you like it!!The image is taken with Achromatic 152/900 Telescope Service and great Apogee Alta U9 on the granitic Astrophysics 1200 GTO. Details are in image.All new images are labeled with a bright "NEW"If you want visit my website please link to:http://www.skytoa.it/ For looking Luminance please visit this link:http://www.skytoa.it/galleria_nebulose_halfa.html For looking a Colour please visit this link:http://www.skytoa.it/galleria_nebulose.htmlAny comments are welcome!Thanks a lot for looking,Matteo Morino T.O.A. Torrazzo Osservatorio Astronomicodi Matteo Morinowww.skytoa.ittoa@skyto a.it



-->

-->----Messaggio originale----Da: toa.mm@...: 19/10/2009 22.08A: <ap-gto@...>Ogg: [ap-gto] Latest images from Toa Observatory


----Messaggio originale----Da: toa.mm@...: 19/10/2009 22.08A: <ap-gto@...>Ogg: [ap-gto] Latest images from Toa Observatory


----Messaggio originale----Da: toa.mm@...: 19/10/2009 22.08A: <ap-gto@...>Ogg: [ap-gto] Latest images from Toa Observatory





Hi group,These images that I want to share with you all, are always the latest exciting images I've done. I hope that you like it!!The image is taken with Achromatic 152/900 Telescope Service and great Apogee Alta U9 on the granitic Astrophysics 1200 GTO. Details are in image.All new images are labeled with a bright "NEW"If you want visit my website please link to:http://www.skytoa.it/ For looking Luminance please visit this link:http://www.skytoa.it/galleria_nebulose_halfa.html For looking a Colour please visit this link:http://www.skytoa.it/galleria_nebulose.htmlAny comments are welcome!Thanks a lot for looking,Matteo Morino T.O.A. Torrazzo Osservatorio Astronomicodi Matteo Morinowww.skytoa.ittoa@skyto a.it



-->

-->----Messaggio originale----Da: toa.mm@...: 19/10/2009 22.08A: <ap-gto@...>Ogg: [ap-gto] Latest images from Toa Observatory





Hi group,These images that I want to share with you all, are always the latest exciting images I've done. I hope that you like it!!The image is taken with Achromatic 152/900 Telescope Service and great Apogee Alta U9 on the granitic Astrophysics 1200 GTO. Details are in image.All new images are labeled with a bright "NEW"If you want visit my website please link to:http://www.skytoa.it/ For looking Luminance please visit this link:http://www.skytoa.it/galleria_nebulose_halfa.html For looking a Colour please visit this link:http://www.skytoa.it/galleria_nebulose.htmlAny comments are welcome!Thanks a lot for looking,Matteo Morino T.O.A. Torrazzo Osservatorio Astronomicodi Matteo Morinowww.skytoa.ittoa@skyto a.it



-->

-->----Messaggio originale----Da: toa.mm@...: 19/10/2009 22.08A: <ap-gto@...>Ogg: [ap-gto] Latest images from Toa Observatory


----Messaggio originale----Da: toa.mm@...: 19/10/2009 22.08A: <ap-gto@...>Ogg: [ap-gto] Latest images from Toa Observatory





Hi group,These images that I want to share with you all, are always the latest exciting images I've done. I hope that you like it!!The image is taken with Achromatic 152/900 Telescope Service and great Apogee Alta U9 on the granitic Astrophysics 1200 GTO. Details are in image.All new images are labeled with a bright "NEW"If you want visit my website please link to:http://www.skytoa.it/ For looking Luminance please visit this link:http://www.skytoa.it/galleria_nebulose_halfa.html For looking a Colour please visit this link:http://www.skytoa.it/galleria_nebulose.htmlAny comments are welcome!Thanks a lot for looking,Matteo Morino T.O.A. Torrazzo Osservatorio Astronomicodi Matteo Morinowww.skytoa.ittoa@skyto a.it



-->

-->----Messaggio originale----Da: toa.mm@...: 19/10/2009 22.08A: <ap-gto@...>Ogg: [ap-gto] Latest images from Toa Observatory





Hi group,These images that I want to share with you all, are always the latest exciting images I've done. I hope that you like it!!The image is taken with Achromatic 152/900 Telescope Service and great Apogee Alta U9 on the granitic Astrophysics 1200 GTO. Details are in image.All new images are labeled with a bright "NEW"If you want visit my website please link to:http://www.skytoa.it/ For looking Luminance please visit this link:http://www.skytoa.it/galleria_nebulose_halfa.html For looking a Colour please visit this link:http://www.skytoa.it/galleria_nebulose.htmlAny comments are welcome!Thanks a lot for looking,Matteo Morino T.O.A. Torrazzo Osservatorio Astronomicodi Matteo Morinowww.skytoa.ittoa@skyto a.it



-->

-->----Messaggio originale----Da: toa.mm@...: 19/10/2009 22.08A: <ap-gto@...>Ogg: [ap-gto] Latest images from Toa Observatory


----Messaggio originale----Da: toa.mm@...: 19/10/2009 22.08A: <ap-gto@...>Ogg: [ap-gto] Latest images from Toa Observatory


----Messaggio originale----Da: toa.mm@...: 19/10/2009 22.08A: <ap-gto@...>Ogg: [ap-gto] Latest images from Toa Observatory





Hi group,These images that I want to share with you all, are always the latest exciting images I've done. I hope that you like it!!The image is taken with Achromatic 152/900 Telescope Service and great Apogee Alta U9 on the granitic Astrophysics 1200 GTO. Details are in image.All new images are labeled with a bright "NEW"If you want visit my website please link to:http://www.skytoa.it/ For looking Luminance please visit this link:http://www.skytoa.it/galleria_nebulose_halfa.html For looking a Colour please visit this link:http://www.skytoa.it/galleria_nebulose.htmlAny comments are welcome!Thanks a lot for looking,Matteo Morino T.O.A. Torrazzo Osservatorio Astronomicodi Matteo Morinowww.skytoa.ittoa@skyto a.it



-->

-->----Messaggio originale----Da: toa.mm@...: 19/10/2009 22.08A: <ap-gto@...>Ogg: [ap-gto] Latest images from Toa Observatory





Hi group,These images that I want to share with you all, are always the latest exciting images I've done. I hope that you like it!!The image is taken with Achromatic 152/900 Telescope Service and great Apogee Alta U9 on the granitic Astrophysics 1200 GTO. Details are in image.All new images are labeled with a bright "NEW"If you want visit my website please link to:http://www.skytoa.it/ For looking Luminance please visit this link:http://www.skytoa.it/galleria_nebulose_halfa.html For looking a Colour please visit this link:http://www.skytoa.it/galleria_nebulose.htmlAny comments are welcome!Thanks a lot for looking,Matteo Morino T.O.A. Torrazzo Osservatorio Astronomicodi Matteo Morinowww.skytoa.ittoa@skyto a.it



-->

-->----Messaggio originale----Da: toa.mm@...: 19/10/2009 22.08A: <ap-gto@...>Ogg: [ap-gto] Latest images from Toa Observatory





Hi group,These images that I want to share with you all, are always the latest exciting images I've done. I hope that you like it!!The image is taken with Achromatic 152/900 Telescope Service and great Apogee Alta U9 on the granitic Astrophysics 1200 GTO. Details are in image.All new images are labeled with a bright "NEW"If you want visit my website please link to:http://www.skytoa.it/ For looking Luminance please visit this link:http://www.skytoa.it/galleria_nebulose_halfa.html For looking a Colour please visit this link:http://www.skytoa.it/galleria_nebulose.htmlAny comments are welcome!Thanks a lot for looking,Matteo Morino T.O.A. Torrazzo Osservatorio Astronomicodi Matteo Morinowww.skytoa.ittoa@skyto a.it



-->

-->----Messaggio originale----Da: toa.mm@...: 19/10/2009 22.08A: <ap-gto@...>Ogg: [ap-gto] Latest images from Toa Observatory


----Messaggio originale----Da: toa.mm@...: 19/10/2009 22.08A: <ap-gto@...>Ogg: [ap-gto] Latest images from Toa Observatory





Hi group,These images that I want to share with you all, are always the latest exciting images I've done. I hope that you like it!!The image is taken with Achromatic 152/900 Telescope Service and great Apogee Alta U9 on the granitic Astrophysics 1200 GTO. Details are in image.All new images are labeled with a bright "NEW"If you want visit my website please link to:http://www.skytoa.it/ For looking Luminance please visit this link:http://www.skytoa.it/galleria_nebulose_halfa.html For looking a Colour please visit this link:http://www.skytoa.it/galleria_nebulose.htmlAny comments are welcome!Thanks a lot for looking,Matteo Morino T.O.A. Torrazzo Osservatorio Astronomicodi Matteo Morinowww.skytoa.ittoa@skyto a.it



-->

-->----Messaggio originale----Da: toa.mm@...: 19/10/2009 22.08A: <ap-gto@...>Ogg: [ap-gto] Latest images from Toa Observatory





Hi group,These images that I want to share with you all, are always the latest exciting images I've done. I hope that you like it!!The image is taken with Achromatic 152/900 Telescope Service and great Apogee Alta U9 on the granitic Astrophysics 1200 GTO. Details are in image.All new images are labeled with a bright "NEW"If you want visit my website please link to:http://www.skytoa.it/ For looking Luminance please visit this link:http://www.skytoa.it/galleria_nebulose_halfa.html For looking a Colour please visit this link:http://www.skytoa.it/galleria_nebulose.htmlAny comments are welcome!Thanks a lot for looking,Matteo Morino T.O.A. Torrazzo Osservatorio Astronomicodi Matteo Morinowww.skytoa.ittoa@skyto a.it



-->

-->----Messaggio originale----Da: toa.mm@...: 19/10/2009 22.08A: <ap-gto@...>Ogg: [ap-gto] Latest images from Toa Observatory





Hi group,These images that I want to share with you all, are always the latest exciting images I've done. I hope that you like it!!The image is taken with Achromatic 152/900 Telescope Service and great Apogee Alta U9 on the granitic Astrophysics 1200 GTO. Details are in image.All new images are labeled with a bright "NEW"If you want visit my website please link to:http://www.skytoa.it/ For looking Luminance please visit this link:http://www.skytoa.it/galleria_nebulose_halfa.html For looking a Colour please visit this link:http://www.skytoa.it/galleria_nebulose.htmlAny comments are welcome!Thanks a lot for looking,Matteo Morino T.O.A. Torrazzo Osservatorio Astronomicodi Matteo Morinowww.skytoa.ittoa@skyto a.it



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Latest images from Toa Observatory

toa.mm@libero.it <toa.mm@...>
 

Hi group,These images that I want to share with you all, are always the latest exciting images I've done. I hope that you like it!!The image is taken with Achromatic 152/900 Telescope Service and great Apogee Alta U9 on the granitic Astrophysics 1200 GTO. Details are in image.All new images are labeled with a bright "NEW"If you want visit my website please link to:http://www.skytoa.it/ For looking Luminance please visit this link:http://www.skytoa.it/galleria_nebulose_halfa.html For looking a Colour please visit this link:http://www.skytoa.it/galleria_nebulose.htmlAny comments are welcome!Thanks a lot for looking,Matteo Morino T.O.A. Torrazzo Osservatorio Astronomicodi Matteo Morinowww.skytoa.ittoa@...


Re: Problems with 900GTO

GO <johnd@...>
 

Wally's instructions were very helpful. I was able to eliminate the end play.

Thanks to all for being so helpful and responsive. I only discovered this problem a few days ago and it would appear to be resolved. Can't wait to get under the stars agian!

Regards,

John

--- In ap-gto@..., chris1011@... wrote:

In a message dated 10/19/2009 11:17:14 AM Central Daylight Time,
chris1011@... writes:


"I have also noticed a higher degree of play in the Dec axis and
attempted to adjust that as well. I worked up to the point where the
gears were too
tight and then backed it off a bit. Unfortunately the play was not
eliminated. It looks to be around ½ degree of play or the full FOV in a
12.5mm
eyepiece at 1600mm fl. I have been able to use the mount in the East by
loading the balance more in that direction than I would normally.
This "play" is simply the worm and worm wheel is not in mesh. You need to
put the two gears fully in mesh.

If the worms are in mesh, then it is possible that the end bearings on the
worm gear are loose and needs to be tightened. This requires a bit of help
from our service department if you want to do it yourself. You can check the
end play of the worm by removing the small black anodized cover knob on the
motor gearbox to expose the end of the worm gear. Then by rocking the RA
axis back and forth you can see whether this gear is moving sideways. It should
stay perfectly still and not move when pressure is applied to the axis in
both directions. If you see any movement, then the bearing retainer needs to
be tightened. Call the office and ask to speak with Wally about tightening
the end play bearing.

Rolando


[Non-text portions of this message have been removed]


Re: Problem with Loaner Keypad

GO <johnd@...>
 

I conducted the test per Howards instructions and hte keyad will need to be returned.

Tks,
John

--- In ap-gto@..., "jockey_ca" <jockey_ca@...> wrote:

John
What version of the keypad firmware does the loaner have? If it is Ver 4.15 or 4.16 that could be the problem. Both of these firmware versions had a bug that caused the keypad to lock up on start up. Especially when executing the "Return from Park 1" selection. Check out the firmware upgrade section of the Astrophysics website.
Don

--- In ap-gto@..., "GO" <johnd@> wrote:

The loaner keypad sent to me doesn't seem to be working properly.

Upon startup it asked me for a location, I entered location '1', pressed GOTO as instructed, and the keypad appeared to be locked-up. Just sat there for up to 20 min. or so. I rebooted the drive and tried different locations to no avail.

Fortunately I have kept my old keypad and it worked fine for this weekends work.

Could there be a problem with firmware compatability between the keypad and my mount? I have had the mount for many years and do not remember having upgraded the firmware.

The keys are falling off my keypad so I would like to send it in for repair but want to be able to use my mount during the lengthy repair time. Your loaner program is great!

So how do I proceed from this point?

Regards,

John


Re: Problem with Loaner Keypad

Don Anderson
 

John
What version of the keypad firmware does the loaner have? If it is Ver 4.15 or 4.16 that could be the problem. Both of these firmware versions had a bug that caused the keypad to lock up on start up. Especially when executing the "Return from Park 1" selection. Check out the firmware upgrade section of the Astrophysics website.
Don

--- In ap-gto@..., "GO" <johnd@...> wrote:

The loaner keypad sent to me doesn't seem to be working properly.

Upon startup it asked me for a location, I entered location '1', pressed GOTO as instructed, and the keypad appeared to be locked-up. Just sat there for up to 20 min. or so. I rebooted the drive and tried different locations to no avail.

Fortunately I have kept my old keypad and it worked fine for this weekends work.

Could there be a problem with firmware compatability between the keypad and my mount? I have had the mount for many years and do not remember having upgraded the firmware.

The keys are falling off my keypad so I would like to send it in for repair but want to be able to use my mount during the lengthy repair time. Your loaner program is great!

So how do I proceed from this point?

Regards,

John


Problem with Loaner Keypad

GO <johnd@...>
 

The loaner keypad sent to me doesn't seem to be working properly.

Upon startup it asked me for a location, I entered location '1', pressed GOTO as instructed, and the keypad appeared to be locked-up. Just sat there for up to 20 min. or so. I rebooted the drive and tried different locations to no avail.

Fortunately I have kept my old keypad and it worked fine for this weekends work.

Could there be a problem with firmware compatability between the keypad and my mount? I have had the mount for many years and do not remember having upgraded the firmware.

The keys are falling off my keypad so I would like to send it in for repair but want to be able to use my mount during the lengthy repair time. Your loaner program is great!

So how do I proceed from this point?

Regards,

John


Re: Problems with 900GTO

GO <johnd@...>
 

Rolando,
In my last I described how I did what you suggested. I wrote:

"I have also noticed a higher degree of play in the Dec axis and attempted to adjust that as well. I worked up to the point where the gears were too tight and then backed it off a bit. Unfortunately the play was not eliminated. It looks to be around ½ degree of play or the full FOV in a 12.5mm eyepiece at 1600mm fl. I have been able to use the mount in the East by loading the balance more in that direction than I would normally.

I was not able to correct this play and it is a serious problem when calibrating the mount and especially when running a T-Point model. What is my next step to correct this?"

I was adjusting the backlash per your backlash adjustment bulletin. I worked up to the point that the gears were too tight and the overload protection tripped. Even at that point the play was there. Then I backed-off slightly so the gears meshed without overload and I could operate the mount. The play was still there. Afterwards I loaded the mount not to the East per se, but unbalanced it towards the front end of the OTA. this improved things to the point that I was able to use the mount for imaging as long as I didn't go past the meridian.

Perhaps I didn't adjust the backlash correctly? I took my time and thought I followed the process. But I am new at this and welcome any thoughts or ideas how I can remove the play and improve my mounts accuracy and performance.

Regards,
John

--- In ap-gto@..., chris1011@... wrote:

In a message dated 10/18/2009 6:43:18 PM Central Daylight Time,
johnd@... writes:


It looks to be around ½ degree of play or the full FOV in a 12.5mm
eyepiece at 1600mm fl.
If you have 1/2 degree of "play" what you really have is the worm and worm
wheel not in mesh. Adjust the mesh to the point where you cannot feel any
movement in the RA axis when you push on the scope (or counterweight shaft) in
the East-West direction.

Rolando


[Non-text portions of this message have been removed]


For Sale on Astromart Auctions - Astro-Physics 180 f/7

Anthony Ayiomamitis <anthony@...>
 


Re: Problems with 900GTO

Roland Christen
 

In a message dated 10/19/2009 11:17:14 AM Central Daylight Time,
chris1011@... writes:


"I have also noticed a higher degree of play in the Dec axis and
attempted to adjust that as well. I worked up to the point where the
gears were too
tight and then backed it off a bit. Unfortunately the play was not
eliminated. It looks to be around ½ degree of play or the full FOV in a
12.5mm
eyepiece at 1600mm fl. I have been able to use the mount in the East by
loading the balance more in that direction than I would normally.
This "play" is simply the worm and worm wheel is not in mesh. You need to
put the two gears fully in mesh.

If the worms are in mesh, then it is possible that the end bearings on the
worm gear are loose and needs to be tightened. This requires a bit of help
from our service department if you want to do it yourself. You can check the
end play of the worm by removing the small black anodized cover knob on the
motor gearbox to expose the end of the worm gear. Then by rocking the RA
axis back and forth you can see whether this gear is moving sideways. It should
stay perfectly still and not move when pressure is applied to the axis in
both directions. If you see any movement, then the bearing retainer needs to
be tightened. Call the office and ask to speak with Wally about tightening
the end play bearing.

Rolando


[Non-text portions of this message have been removed]


Re: Problems with 900GTO

Roland Christen
 

In a message dated 10/19/2009 11:06:17 AM Central Daylight Time,
johnd@... writes:


"I have also noticed a higher degree of play in the Dec axis and
attempted to adjust that as well. I worked up to the point where the gears were too
tight and then backed it off a bit. Unfortunately the play was not
eliminated. It looks to be around ½ degree of play or the full FOV in a 12.5mm
eyepiece at 1600mm fl. I have been able to use the mount in the East by
loading the balance more in that direction than I would normally.
This "play" is simply the worm and worm wheel is not in mesh. You need to
put the two gears fully in mesh.

Rolando


Re: Problems with 900GTO

Roland Christen
 

In a message dated 10/18/2009 6:43:18 PM Central Daylight Time,
johnd@... writes:


It looks to be around ½ degree of play or the full FOV in a 12.5mm
eyepiece at 1600mm fl.
If you have 1/2 degree of "play" what you really have is the worm and worm
wheel not in mesh. Adjust the mesh to the point where you cannot feel any
movement in the RA axis when you push on the scope (or counterweight shaft) in
the East-West direction.

Rolando


Re: Problems with 900GTO

GO <johnd@...>
 

Rolando,
Thanks for the response and the education. I appreciate the time you spend assisting your clients. My apologies for my lack of knowledge and proper terminology.

I stand corrected I do not see this symptom at <1X. I performed the backlash adjustment and decreased the reverse `jump' but did not eliminate it. It would seem that changing the backlash setting (RA) didn't make much difference. Perhaps I made a mistake there. There is very little, but some, play in that axis.

I have also noticed a higher degree of play in the Dec axis and attempted to adjust that as well. I worked up to the point where the gears were too tight and then backed it off a bit. Unfortunately the play was not eliminated. It looks to be around ½ degree of play or the full FOV in a 12.5mm eyepiece at 1600mm fl. I have been able to use the mount in the East by loading the balance more in that direction than I would normally.

I was not able to correct this play and it is a serious problem when calibrating the mount and especially when running a T-Point model. What is my next step to correct this?

Regards,
John


Re: Problems with 900GTO

uthin8er
 

Yep, sounds like a backlash setting to me. Make sure your keypad and any other software that may be connected to the mount are set to zero.

--- In ap-gto@..., chris provost <lineman_16735@...> wrote:

If your using the Ascom driver then the backlash is set too high.  I think it defaults to 15?  Set it for 0 and see what happens.
 
Chris



--- On Fri, 10/16/09, GO <johnd@...> wrote:


From: GO <johnd@...>
Subject: [ap-gto] Re: Problems with 900GTO
To: ap-gto@...
Date: Friday, October 16, 2009, 5:09 PM


 



Didn't see my post from yesterday on the web site so am retransmitting it again. Didn't do any work last night as the wind was too strong to roll off the roof. Forecast for tonight good so I will be able to try and correct this problem.

Please see below for my response to your email.

John

----- Original Message -----
From:
To: ap-gto@yahoogroups. com
Sent: Thu Oct 15 18:24
Subject: Fwd: Re: [ap-gto] Problems with 900GTO

Rolando,

First, a reply within two hours is a great response. No complaint from me! There really hasn't been enough time for a response from anyone else.

1) I am slewing to the East via the keypad and veiwing the results in the eyepiece. I am seeing this initial movement in the opposite direction and then the 'drift' after the keypad is released at speeds from 1 to 600. Just haven't tried a speed less than 1. I first noticed this when moving the mount at 1, 12, and 64 while centering stars for calibration and T-Point modeling.

2) Yes, I know there is a difference between slewing and guiding. I had just assumed that if I was seeing this abberation when moving the mount to center stars that it would also negatively effect my auto-guiding. It certainly would for manual guiding. Is this not true? I thought this was probably the reason I am not able to pass initial guiding tests. But I have to say I haven't even gotten past that point in attempting to guide. I had jumped to the conclusion that the problem was mechanically related.

Will try to test if this is happening when I move the mount via my computer this evening if the wind dies down a bit and will let you know. I can also test it with a new loaner keypad you sent me and with my keypad which I haven't sent in for repair to some of the keys which have fallen/broken off if that would be helpful.

Any other tests you would like for me to perform?

Thanks for your help,

John

--- In ap-gto@yahoogroups. com, "GO" <johnd@> wrote:

I am still having problems with my 900GTO mount. The problems are: When slewing to the East the mount moves/jumps backwards a small amount before going in the right direction. After the command has been terminated it then continues to drift in the correct direction.

I can't pass even the most basic auto-guide test and feel this has to be corrected before I can even expect to auto-guide.

Info: The mount was in storage for six years. I did have a problem with the spur gear being loose and have tightened it per instructions. I have inspected it recently and it is still firmly attached. I have adjusted the backlash recently and that doesn't seem to change this symptom. I did at one point have the backlash too tightand still saw this symptom even though the mount's slewing was labored. I stopped this immediately and readjusted!


When this is happening I am looking to the East. The balancing of the mount is pretty close.

Thanks,
John


















[Non-text portions of this message have been removed]


Re: Drag in RA on AP-900

gremlinastro
 

Joel it could be the plugs in the RA lock sockets need replacing. If so this is an easy fix as AP can supply replacement plugs as well as a tool to remove the old ones.

Dave.

joelwhicker wrote:


Hello All,

I recently purchased a used AP-900GTO about 6 years old, but in really good shape. Everything is perfect, except one thing that has me guessing a little.

In RA when the scope is rotated (without locks) toward the east, about half way to horizontal there is a "drag". If you listen closely, it is audible. When free-wheeling the balanced load, the "drag" will bring everything to a stop. Not abruptly, but definitely slows things down.

When the OTA is rotated west, all is smooth and drag free.

In all fairness, I received the mount pack directly in styrofoam peanuts that found their way everywhere. I used compressed air to blow everything out of both dec and RA assemblies. Is it possible some debris got into my RA bearing, or is this normal?

BTW, under power, there is absolutely no noticeable effect. Any ideas?

Thanks and regards,

Joel

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*Dave Grennan
*Raheny Observatory (MPC J41) - Dublin Ireland
E-Mail: dave@...
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Drag in RA on AP-900

joelwhicker
 

Hello All,

I recently purchased a used AP-900GTO about 6 years old, but in really good shape. Everything is perfect, except one thing that has me guessing a little.

In RA when the scope is rotated (without locks) toward the east, about half way to horizontal there is a "drag". If you listen closely, it is audible. When free-wheeling the balanced load, the "drag" will bring everything to a stop. Not abruptly, but definitely slows things down.

When the OTA is rotated west, all is smooth and drag free.

In all fairness, I received the mount pack directly in styrofoam peanuts that found their way everywhere. I used compressed air to blow everything out of both dec and RA assemblies. Is it possible some debris got into my RA bearing, or is this normal?

BTW, under power, there is absolutely no noticeable effect. Any ideas?

Thanks and regards,

Joel


Re: Problems with 900GTO

chris provost <lineman_16735@...>
 

If your using the Ascom driver then the backlash is set too high.  I think it defaults to 15?  Set it for 0 and see what happens.
 
Chris

--- On Fri, 10/16/09, GO <johnd@...> wrote:


From: GO <johnd@...>
Subject: [ap-gto] Re: Problems with 900GTO
To: ap-gto@...
Date: Friday, October 16, 2009, 5:09 PM


 



Didn't see my post from yesterday on the web site so am retransmitting it again. Didn't do any work last night as the wind was too strong to roll off the roof. Forecast for tonight good so I will be able to try and correct this problem.

Please see below for my response to your email.

John

----- Original Message -----
From:
To: ap-gto@yahoogroups. com
Sent: Thu Oct 15 18:24
Subject: Fwd: Re: [ap-gto] Problems with 900GTO

Rolando,

First, a reply within two hours is a great response. No complaint from me! There really hasn't been enough time for a response from anyone else.

1) I am slewing to the East via the keypad and veiwing the results in the eyepiece. I am seeing this initial movement in the opposite direction and then the 'drift' after the keypad is released at speeds from 1 to 600. Just haven't tried a speed less than 1. I first noticed this when moving the mount at 1, 12, and 64 while centering stars for calibration and T-Point modeling.

2) Yes, I know there is a difference between slewing and guiding. I had just assumed that if I was seeing this abberation when moving the mount to center stars that it would also negatively effect my auto-guiding. It certainly would for manual guiding. Is this not true? I thought this was probably the reason I am not able to pass initial guiding tests. But I have to say I haven't even gotten past that point in attempting to guide. I had jumped to the conclusion that the problem was mechanically related.

Will try to test if this is happening when I move the mount via my computer this evening if the wind dies down a bit and will let you know. I can also test it with a new loaner keypad you sent me and with my keypad which I haven't sent in for repair to some of the keys which have fallen/broken off if that would be helpful.

Any other tests you would like for me to perform?

Thanks for your help,

John

--- In ap-gto@yahoogroups. com, "GO" <johnd@...> wrote:

I am still having problems with my 900GTO mount. The problems are: When slewing to the East the mount moves/jumps backwards a small amount before going in the right direction. After the command has been terminated it then continues to drift in the correct direction.

I can't pass even the most basic auto-guide test and feel this has to be corrected before I can even expect to auto-guide.

Info: The mount was in storage for six years. I did have a problem with the spur gear being loose and have tightened it per instructions. I have inspected it recently and it is still firmly attached. I have adjusted the backlash recently and that doesn't seem to change this symptom. I did at one point have the backlash too tightand still saw this symptom even though the mount's slewing was labored. I stopped this immediately and readjusted!


When this is happening I am looking to the East. The balancing of the mount is pretty close.

Thanks,
John


Re: Problems with 900GTO

GO <johnd@...>
 

Didn't see my post from yesterday on the web site so am retransmitting it again. Didn't do any work last night as the wind was too strong to roll off the roof. Forecast for tonight good so I will be able to try and correct this problem.

Please see below for my response to your email.

John

----- Original Message -----
From:
To: ap-gto@...
Sent: Thu Oct 15 18:24
Subject: Fwd: Re: [ap-gto] Problems with 900GTO




Rolando,

First, a reply within two hours is a great response. No complaint from me! There really hasn't been enough time for a response from anyone else.

1) I am slewing to the East via the keypad and veiwing the results in the eyepiece. I am seeing this initial movement in the opposite direction and then the 'drift' after the keypad is released at speeds from 1 to 600. Just haven't tried a speed less than 1. I first noticed this when moving the mount at 1, 12, and 64 while centering stars for calibration and T-Point modeling.

2) Yes, I know there is a difference between slewing and guiding. I had just assumed that if I was seeing this abberation when moving the mount to center stars that it would also negatively effect my auto-guiding. It certainly would for manual guiding. Is this not true? I thought this was probably the reason I am not able to pass initial guiding tests. But I have to say I haven't even gotten past that point in attempting to guide. I had jumped to the conclusion that the problem was mechanically related.

Will try to test if this is happening when I move the mount via my computer this evening if the wind dies down a bit and will let you know. I can also test it with a new loaner keypad you sent me and with my keypad which I haven't sent in for repair to some of the keys which have fallen/broken off if that would be helpful.

Any other tests you would like for me to perform?

Thanks for your help,

John



--- In ap-gto@..., "GO" <johnd@...> wrote:

I am still having problems with my 900GTO mount. The problems are: When slewing to the East the mount moves/jumps backwards a small amount before going in the right direction. After the command has been terminated it then continues to drift in the correct direction.

I can't pass even the most basic auto-guide test and feel this has to be corrected before I can even expect to auto-guide.

Info: The mount was in storage for six years. I did have a problem with the spur gear being loose and have tightened it per instructions. I have inspected it recently and it is still firmly attached. I have adjusted the backlash recently and that doesn't seem to change this symptom. I did at one point have the backlash too tightand still saw this symptom even though the mount's slewing was labored. I stopped this immediately and readjusted!


When this is happening I am looking to the East. The balancing of the mount is pretty close.

Thanks,
John