A Question Regarding an AP900 Mount


marsh.family
 

Hi Everyone

I'm looking for some insight.  Last night while using my AP900 mount, my software was sending the mount to a location in the sky and I could hear the dec axis motor but there was no movement of the dec axis.

When I tried to manually slew the mount via hand controller, it moved ok.  And later did slew to other locations.

I am using the ASIair pro system to control the mount

When I grasp the dec axis and try to move it, it seems to be solid with no backlash.

Any insight into what may have happened to the dec axis not moving?  

Thanks,

Chris


 

Chris,

 

What  CPx are you using to drive the motors? A CP3 or a CP4?

 

If the keypad has no issue moving the dec axis, then the motors and the mount are fine. I suspect a software issue or cable issue. I would start with using a different cable and connector to reach the CPx. For example, on a CP3 you could swap out your serial cable and use the second serial port.

 

Liam Plybon

Astro-Physics

 

From: main@ap-gto.groups.io <main@ap-gto.groups.io> On Behalf Of marsh.family@...
Sent: Thursday, April 8, 2021 10:59 AM
To: main@ap-gto.groups.io
Subject: [ap-gto] A Question Regarding an AP900 Mount

 

Hi Everyone

I'm looking for some insight.  Last night while using my AP900 mount, my software was sending the mount to a location in the sky and I could hear the dec axis motor but there was no movement of the dec axis.

When I tried to manually slew the mount via hand controller, it moved ok.  And later did slew to other locations.

I am using the ASIair pro system to control the mount

When I grasp the dec axis and try to move it, it seems to be solid with no backlash.

Any insight into what may have happened to the dec axis not moving?  

Thanks,

Chris


marsh.family
 

Liam, thx for the quick reply.

I am using the CP2 as my mount is from the early 2000's.

I'm connected from the ASI Pro via a USB to serial cable.

You don't think it could be the CP2 to dec axis cable? 

I've also noticed poor tracking even unguided. In a 5 minute exposure I sometimes see a double image. Which is why I'm questioning the CP2 to dec axis cable and not the serial cable.

Thoughts?

Chris



Sent from my Galaxy


-------- Original message --------
From: Liam Plybon <liam@...>
Date: 2021-04-08 12:08 p.m. (GMT-05:00)
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] A Question Regarding an AP900 Mount

Chris,

 

What  CPx are you using to drive the motors? A CP3 or a CP4?

 

If the keypad has no issue moving the dec axis, then the motors and the mount are fine. I suspect a software issue or cable issue. I would start with using a different cable and connector to reach the CPx. For example, on a CP3 you could swap out your serial cable and use the second serial port.

 

Liam Plybon

Astro-Physics

 

From: main@ap-gto.groups.io <main@ap-gto.groups.io> On Behalf Of marsh.family@...
Sent: Thursday, April 8, 2021 10:59 AM
To: main@ap-gto.groups.io
Subject: [ap-gto] A Question Regarding an AP900 Mount

 

Hi Everyone

I'm looking for some insight.  Last night while using my AP900 mount, my software was sending the mount to a location in the sky and I could hear the dec axis motor but there was no movement of the dec axis.

When I tried to manually slew the mount via hand controller, it moved ok.  And later did slew to other locations.

I am using the ASIair pro system to control the mount

When I grasp the dec axis and try to move it, it seems to be solid with no backlash.

Any insight into what may have happened to the dec axis not moving?  

Thanks,

Chris


Kenneth Tan
 

I think the issue is with the asi air.  I have experienced the same problem where it fails to move with a goto command from the asi air app. I either try multiple times or move it with the hand controller a little bit and then click the goto on the app again and it moves properly .

I was wondering if it is some delay from the wireless connection from the ipad to the asi air. Also possible is the cable/ wifi problem from mount to asi air. I cannot be sure which. 
By the way I am running the AP Mach2 ae with gtocp5 . I had to use gtocp2 settings on the app for It to work. Therefore, my problem may have a different etiology

On Fri, 9 Apr 2021 at 00:02, <marsh.family@...> wrote:
Hi Everyone

I'm looking for some insight.  Last night while using my AP900 mount, my software was sending the mount to a location in the sky and I could hear the dec axis motor but there was no movement of the dec axis.

When I tried to manually slew the mount via hand controller, it moved ok.  And later did slew to other locations.

I am using the ASIair pro system to control the mount

When I grasp the dec axis and try to move it, it seems to be solid with no backlash.

Any insight into what may have happened to the dec axis not moving?  

Thanks,

Chris


 

Kenneth,

 

Please email me directly at liam@... so that we can take a look.

 

Thanks,

Liam

 

From: main@ap-gto.groups.io <main@ap-gto.groups.io> On Behalf Of Kenneth Tan
Sent: Thursday, April 8, 2021 12:33 PM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] A Question Regarding an AP900 Mount

 

I think the issue is with the asi air.  I have experienced the same problem where it fails to move with a goto command from the asi air app. I either try multiple times or move it with the hand controller a little bit and then click the goto on the app again and it moves properly .

 

I was wondering if it is some delay from the wireless connection from the ipad to the asi air. Also possible is the cable/ wifi problem from mount to asi air. I cannot be sure which. 

By the way I am running the AP Mach2 ae with gtocp5 . I had to use gtocp2 settings on the app for It to work. Therefore, my problem may have a different etiology

 

On Fri, 9 Apr 2021 at 00:02, <marsh.family@...> wrote:

Hi Everyone

I'm looking for some insight.  Last night while using my AP900 mount, my software was sending the mount to a location in the sky and I could hear the dec axis motor but there was no movement of the dec axis.

When I tried to manually slew the mount via hand controller, it moved ok.  And later did slew to other locations.

I am using the ASIair pro system to control the mount

When I grasp the dec axis and try to move it, it seems to be solid with no backlash.

Any insight into what may have happened to the dec axis not moving?  

Thanks,

Chris


 

I just realized I never fully addressed your problem! Sorry Chris!

You can swap the RA and Dec cables on the 900 mount. Depending on your cable harness setup, this might require some contortion on your behalf. If you switch the cables and the problem follows the Dec cable, it is either the cable or the CP2. If the problem stays on the Dec axis, the problem is mechanical in nature. 

Email me directly when you have tried this, so we can work on it together. 

--
Liam Plybon
Astro-Physics